RESUMEN
Gestational diabetes mellitus (GDM) affects 5-10% of pregnancies and increases the risk of fetal and maternal adverse outcomes. Interestingly, the vascular response to AngII is decreased by pregnancy while the response is increased by diabetes. It remains unclear how GDM affects vascular tone and how angiotensin II receptors contribute to these changes. In this work, we sought to establish the vascular impact of a hypercaloric diet-induced GDM through changes in AT1 and AT2 receptor's expression. Female rats fed for 7 weeks with standard (SD) or hypercaloric (HD) diet were divided at week 4. Half of the rats of each group were mated to become pregnant and those fed with a HD developed GDM. AngII-induced vasoconstriction was measured in thoracic or abdominal aorta rings using a conventional isolated organ bath and AT1 and AT2 receptors were searched by immunohistochemistry. Experiments where conducted on the pregnant standard diet group (PSD) and the pregnant hypercaloric-gestational diabetes mellitus group (PHD-GDM). Vasoconstriction was reduced in the thoracic aorta (P < 0.05 vs PSD) but increased in the abdominal aorta of PHD-GDM rats (P < 0.05 vs PSD). Blockade of AT2 receptors using PD123319 decreased vasoconstriction, particularly in the abdominal aorta of PHD-GDM animals (P < 0.05 vs PSD). PHD-GDM increased AT1 receptors expression (P < 0.05 vs PSD). Also, PHD-GDM reverted physiologic hypoglycemia and hypotension of healthy pregnancy. Findings provide new insight into the hypercaloric diet induced damage on the vasculature during pregnancy.
Asunto(s)
Aorta Abdominal/metabolismo , Aorta Torácica/metabolismo , Diabetes Gestacional/metabolismo , Endotelio Vascular/metabolismo , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Angiotensina Tipo 2/metabolismo , Vasoconstricción , Angiotensina II/farmacología , Antagonistas de Receptores de Angiotensina/farmacología , Animales , Aorta Abdominal/efectos de los fármacos , Aorta Abdominal/fisiopatología , Aorta Torácica/efectos de los fármacos , Aorta Torácica/fisiopatología , Diabetes Gestacional/fisiopatología , Modelos Animales de Enfermedad , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiopatología , Femenino , Embarazo , Ratas Wistar , Receptor de Angiotensina Tipo 1/agonistas , Receptor de Angiotensina Tipo 2/agonistas , Transducción de Señal , Vasoconstricción/efectos de los fármacos , Vasoconstrictores/farmacologíaRESUMEN
OBJECTIVE: Tissue-engineered vascular grafts containing adipose-derived mesenchymal stem cells offer an alternative to small-diameter vascular grafts currently used in cardiac and lower-extremity revascularization procedures. Adipose-derived, mesenchymal stem cell-infused, tissue-engineered vascular grafts have been shown to promote remodeling and vascular homeostasis in vivo and offer a possible treatment solution for those with cardiovascular disease. Unfortunately, the time needed to cultivate adipose-derived mesenchymal stem cells remains a large hurdle for tissue-engineered vascular grafts as a treatment option. The purpose of this study was to determine if stromal vascular fraction (known to contain progenitor cells) seeded tissue-engineered vascular grafts would remain patent in vivo and remodel, allowing for a "same-day" process for tissue-engineered vascular graft fabrication and implantation. METHODS: Stromal vascular fraction, obtained from adult human adipose tissue, was seeded within 4 hours after acquisition from the patient onto poly(ester urethane)urea bilayered scaffolds using a customized rotational vacuum seeding device. Constructs were then surgically implanted as abdominal aortic interposition grafts in Lewis rats. RESULTS: Findings revealed patency in 5 of 7 implanted scaffolds at 8 weeks, along with neotissue formation and remodeling occurring in patent tissue-engineered vascular grafts. Patency was documented using angiography and gross inspection, and remodeling and vascular components were detected using immunofluorescent chemistry. CONCLUSIONS: A "same-day" cell-seeded, tissue-engineered vascular graft can remain patent after implantation in vivo, with neotissue formation and remodeling occurring by 8 weeks.
Asunto(s)
Tejido Adiposo/citología , Aorta Abdominal/cirugía , Bioprótesis , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Trasplante de Células Madre/instrumentación , Células del Estroma/fisiología , Células del Estroma/trasplante , Ingeniería de Tejidos/métodos , Andamios del Tejido , Adulto , Animales , Aorta Abdominal/metabolismo , Aorta Abdominal/patología , Aorta Abdominal/fisiopatología , Biomarcadores/metabolismo , Células Cultivadas , Estudios de Factibilidad , Femenino , Humanos , Persona de Mediana Edad , Neointima , Fenotipo , Diseño de Prótesis , Ratas Endogámicas Lew , Células del Estroma/metabolismo , Factores de Tiempo , Trasplante Heterólogo , Grado de Desobstrucción Vascular , Remodelación Vascular , Flujo de TrabajoRESUMEN
OBJECTIVE: One of the rate-limiting barriers within the field of vascular tissue engineering is the lengthy fabrication time associated with expanding appropriate cell types in culture. One particularly attractive cell type for this purpose is the adipose-derived mesenchymal stem cell (AD-MSC), which is abundant and easily harvested from liposuction procedures. Even this cell type has its drawbacks, however, including the required culture period for expansion, which could pose risks of cellular transformation or contamination. Eliminating culture entirely would be ideal to avoid these concerns. In this study, we used the raw population of cells obtained after digestion of human liposuction aspirates, known as the stromal vascular fraction (SVF), as an abundant, culture-free cell source for tissue-engineered vascular grafts (TEVGs). METHODS: SVF cells and donor-paired cultured AD-MSCs were first assessed for their abilities to differentiate into vascular smooth muscle cells (SMCs) after angiotensin II stimulation and to secrete factors (eg, conditioned media) that promote SMC migration. Next, both cell types were incorporated into TEVG scaffolds, implanted as an aortic graft in a Lewis rat model, and assessed for their patency and composition. RESULTS: In general, the human SVF cells were able to perform the same functions as AD-MSCs isolated from the same donor by culture expansion. Specifically, cells within the SVF performed two important functions; namely, they were able to differentiate into SMCs (SVF calponin expression: 16.4% ± 7.7% vs AD-MSC: 19.9%% ± 1.7%) and could secrete promigratory factors (SVF migration rate relative to control: 3.1 ± 0.3 vs AD-MSC: 2.5 ± 0.5). The SVF cells were also capable of being seeded within biodegradable, elastomeric, porous scaffolds that, when implanted in vivo for 8 weeks, generated patent TEVGs (SVF: 83% patency vs AD-MSC: 100% patency) populated with primary vascular components (eg, SMCs, endothelial cells, collagen, and elastin). CONCLUSIONS: Human adipose tissue can be used as a culture-free cell source to create TEVGs, laying the groundwork for the rapid production of cell-seeded grafts.
Asunto(s)
Tejido Adiposo/irrigación sanguínea , Bioprótesis , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Músculo Liso Vascular/trasplante , Miocitos del Músculo Liso/trasplante , Células del Estroma/trasplante , Ingeniería de Tejidos/métodos , Adulto , Angiotensina II/farmacología , Animales , Aorta Abdominal/metabolismo , Aorta Abdominal/patología , Aorta Abdominal/cirugía , Implantación de Prótesis Vascular/métodos , Diferenciación Celular , Movimiento Celular , Separación Celular , Células Cultivadas , Femenino , Humanos , Lipectomía , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/metabolismo , Fenotipo , Ratas Endogámicas Lew , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismo , Factores de Tiempo , Andamios del TejidoRESUMEN
Obstructive sleep apnea (OSA) is an independent risk factor for cardiovascular diseases such as systemic arterial hypertension, ischemic heart disease, stroke, heart failure, atrial fibrillation, and cardiac sudden death. The pathogenesis of cardiovascular disease in OSA is thought to be induced primarily by chronic intermittent hypoxia (CIH), a specific pattern of change in oxygenation during sleep. However, the underlying mechanisms of CIH-induced vasculature injury and gender differences are not well documented. The iTRAQ Quantitative Proteomic method enables analysis of a number of different proteins among several groups. Thus, we explored gender differences in protein expression in the vascular walls of mice exposed to CIH. C57BL/6J mice of each gender were exposed to CIH with a fractional inspired O2 (FiO2) nadir of 5% or control, with a treatment time of 8 h/day for 28 days. Differential proteins related to CIH-induced vascular injury between genders were identified using iTRAQ proteomic technology. A total of 163 proteins were identified, of which 34 showed significant differences between genders, which may correlate with vascular injury by CIH. Twenty up-regulated proteins and 14 downregulated proteins were observed in female mice compared with male mice. We identified different vascular proteins expressed under CIH between genders, suggesting that these proteins may be biomarkers of vascular injury by CIH.
Asunto(s)
Aorta Abdominal/metabolismo , Hipoxia/metabolismo , Proteoma , Proteómica , Animales , Aorta Abdominal/lesiones , Aorta Abdominal/patología , Biología Computacional , Modelos Animales de Enfermedad , Femenino , Masculino , Ratones , Proteómica/métodos , Factores Sexuales , Apnea Obstructiva del Sueño/metabolismoRESUMEN
It has been described renal damage in rats with vascular calcification. The organic anion transporter 5 (Oat5) is only expressed in kidney, and its urinary excretion was proposed as potential early biomarker of renal injury. The aim of this study was to evaluate the Oat5 renal expression and its urinary excretion in an experimental model of vascular calcification in comparison with traditional markers of renal injury. Vascular calcification was obtained by the administration of an overdose of vitamin D3 (300,000 IU/kg, b.w., i.m.) to male Wistar rats. Oat5 urinary abundance was evaluated by Western blotting. Traditional markers of renal injury, such as creatinine and urea plasma levels, urinary protein levels, and urinary alkaline phosphatase (AP) activity, were determined using commercial kits. Histology was assessed by hematoxylin/eosin staining. Oat5 renal expression was evaluated by Western blotting and by immunohistochemistry. An increased expression of Oat5 in renal homogenates, in apical membranes, and in its urinary excretion was observed in rats with vascular calcification. The traditional parameters used to evaluate renal function were not modified, with the exception of histology. It is possible to postulate the urinary excretion of Oat5 as a potential noninvasive biomarker of renal injury associated with vascular calcification.
Asunto(s)
Transportadores de Ácidos Dicarboxílicos/metabolismo , Transportadores de Ácidos Dicarboxílicos/orina , Riñón/metabolismo , Calcificación Vascular/orina , Fosfatasa Alcalina/orina , Animales , Aorta Abdominal/metabolismo , Aorta Abdominal/patología , Aorta Abdominal/fisiopatología , Presión Sanguínea , Calcio/metabolismo , Inmunohistoquímica , Masculino , Ratas , Ratas Wistar , Sístole , Calcificación Vascular/patología , Calcificación Vascular/fisiopatologíaRESUMEN
BACKGROUND: Chronic allograft vasculopathy (CAV) is an important cause of graft loss. Considering the immune inflammatory events involved in the development of CAV, therapeutic approaches to target this process are of relevance. Human amniotic fluid-derived stem cells (hAFSCs), a class of fetal, pluripotent stem cells with intermediate characteristics between embryonic and adult stem cells, display immunomodulatory properties. hAFSCs express mesenchymal and embryonic markers, show high proliferation rates; however, they do not induce tumor formation, and their use does not raise ethical issues. Thus, we sought to investigate the effect of hAFSC on CAV in a model of aorta transplantation. METHODS: Orthotopic aorta transplantation was performed using Fisher (F344) rats as donors and Lewis rats as recipients. Rats were divided into three groups: syngeneic (SYNG), untreated F344 receiving aorta from F344 (n = 8); allogeneic (ALLO), Lewis rats receiving allogeneic aorta from F344 (n = 8); and ALLO + hAFSC, ALLO rats treated with hAFSC (10(6) cells; n = 8). Histological analysis and immunohistochemistry were performed 30 days posttransplantation. RESULTS: The ALLO group developed a robust aortic neointimal formation (208.7 ± 25.4 µm) accompanied by a significant high number of ED1+ (4845 ± 841 cells/mm2) and CD43+ cells (4064 ± 563 cells/mm2), and enhanced expression of α-smooth muscle actin in the neointima (25 ± 6%). Treatment with hAFSC diminished neointimal thickness (180.7 ± 23.7 µm) and induced a significant decrease of ED1+ (1100 ± 276 cells/mm2), CD43+ cells (1080 ± 309 cells/µm2), and α-smooth muscle actin expression 8 ± 3% in the neointima. CONCLUSIONS: These preliminary results showed that hAFSC suppressed inflammation and myofibroblast migration to the intima, which may contribute to ameliorate vascular changes in CAV.
Asunto(s)
Líquido Amniótico/citología , Aorta Abdominal/trasplante , Enfermedades de la Aorta/prevención & control , Células Madre Fetales/trasplante , Trasplante de Órganos/efectos adversos , Células Madre Pluripotentes/trasplante , Actinas/metabolismo , Animales , Aorta Abdominal/inmunología , Aorta Abdominal/metabolismo , Aorta Abdominal/patología , Enfermedades de la Aorta/etiología , Enfermedades de la Aorta/inmunología , Enfermedades de la Aorta/metabolismo , Enfermedades de la Aorta/patología , Biomarcadores/metabolismo , Movimiento Celular , Células Cultivadas , Células Madre Fetales/inmunología , Células Madre Fetales/metabolismo , Humanos , Inmunohistoquímica , Masculino , Miofibroblastos/metabolismo , Miofibroblastos/patología , Neointima , Células Madre Pluripotentes/inmunología , Células Madre Pluripotentes/metabolismo , Ratas , Ratas Endogámicas F344 , Ratas Endogámicas Lew , Factores de TiempoRESUMEN
BACKGROUND/AIMS: Calcium overload in vascular smooth muscle is a highly pathogenic event, which progresses with advancing age. Old patients are polymedicated, and several pharmacotherapeutic agents circulate in the plasma as organic anions. The organic anion transporters 1 and 3 (Oat1 and Oat3) are present in renal basolateral membranes, which transport organic anions of pharmacological and physiological interest. This study was designed to evaluate the renal expression and function of Oat1 and Oat3 in rats with vascular calcification. METHODS: Vascular calcification was induced by administration of a single dose of vitamin D(3) (300,000 UI/ kg b.w., i.m.) to male Wistar rats 10 days before the experiments. Oat1 and Oat3 expression was assessed by immunoblotting, immunohistochemistry and reverse-transcriptase polymerase chain reaction. The renal clearance of p-aminohippurate (PAH, a prototypical organic anion, substrate of Oat1 and Oat3) was measured by conventional clearance techniques. RESULTS: Oat1 and Oat3 protein levels showed an increase in plasma membranes of renal proximal tubules of treated animals, where both transporters are functional. This could explain the increase observed in the renal clearance of PAH in treated rats. CONCLUSIONS: These results suggest the relevance of considering the existence of vascular calcification, which is common in ageing, when organic anion drugs are prescribed.
Asunto(s)
Membrana Celular/metabolismo , Riñón/fisiología , Músculo Liso Vascular/fisiopatología , Proteína 1 de Transporte de Anión Orgánico/fisiología , Transportadores de Anión Orgánico Sodio-Independiente/fisiología , Calcificación Vascular/fisiopatología , Animales , Aorta Abdominal/metabolismo , Presión Arterial , Calcio/metabolismo , Colecalciferol , Modelos Animales de Enfermedad , Riñón/patología , Masculino , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Calcificación Vascular/inducido químicamente , Calcificación Vascular/metabolismo , Ácido p-Aminohipúrico/metabolismoRESUMEN
BACKGROUND: The pathogenesis of abdominal aortic aneurysm is associated with changes of several components of arterial wall. Vascular glycosaminoglycans contribute to the non-thrombogenic activity of blood vessels. We investigated whether modifications of glycosaminoglycans in human abdominal aortic aneurysm affect their anticoagulant properties. METHODS: Glycosaminoglycans were extracted from abdominal aortic aneurysms (n=11) derived from reconstitution surgeries, human abdominal aortas (n=9) from normal organ transplant donors and from preserved (n=10) and atherosclerotic (n=17) segments obtained from autopsy of an old patient. Glycosaminoglycan composition, concentration and anticoagulant activity were determined. RESULTS: Glycosaminoglycans extracted from aneurysms have a more potent anticoagulant activity than those from normal arteries of young adults, mostly due to a relative enrichment of dermatan sulfate, which potentiates heparin cofactor II inhibition of thrombin. Arterial segments of aged patient with severe atherosclerosis showed a glycosaminoglycan composition similar to aneurysms samples. Glycosaminoglycans extracted from these regions showed also a more potent heparin cofactor II-dependent anticoagulant activity than lesion-free areas due to the relative enrichment of dermatan sulfate. CONCLUSION: The anticoagulant activity from abdominal aortic aneurysms is preserved. No modifications particular to the aneurysms were dissociated from those observed in atherosclerosis.
Asunto(s)
Aneurisma de la Aorta Abdominal/metabolismo , Aterosclerosis/metabolismo , Coagulación Sanguínea , Dermatán Sulfato/metabolismo , Heparitina Sulfato/metabolismo , Adolescente , Adulto , Anciano , Envejecimiento/metabolismo , Aorta Abdominal/metabolismo , Aorta Abdominal/fisiología , Aorta Abdominal/fisiopatología , Aneurisma de la Aorta Abdominal/fisiopatología , Aterosclerosis/patología , Aterosclerosis/fisiopatología , Humanos , Persona de Mediana Edad , Adulto JovenRESUMEN
1 The role of the extraendothelial and constitutive isoforms of cyclo-oxygenase-2 (COX-2) in the contractile effect of angiotensin II (Ang II) was investigated using thoracic and abdominal aortic rings without endothelium from young Wistar rats. 2 Ang II elicited similar contractions in both aortic segments, and the effect was inhibited by pretreatment with NS398 (a selective COX-2 inhibitor) but not SC-560 [selective cyclo-oxygenase-1 (COX-1) inhibitor]. 3 COX-2 mRNA was expressed under basal conditions in both aortic segments. Additionally, Ang II increased COX-2 mRNA expression in the abdominal but not the thoracic segment, while cycloheximide (a protein synthesis inhibitor) did not affect the contractile response to Ang II in either of the two segments; this suggests that the effect is not associated with de novo COX-2 synthesis. 4 In conclusion, the basal amount of COX-2 found in aortic smooth muscle cells is sufficient to explain the production of the prostanoids related to the contractile effect of Ang II. The production of these prostanoids, which are derived from constitutive COX-2, occurs independently of the endothelium vascular system.
Asunto(s)
Angiotensina II/metabolismo , Aorta/metabolismo , Ciclooxigenasa 2/metabolismo , Endotelio Vascular/fisiología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Vasoconstricción/efectos de los fármacos , Animales , Aorta/efectos de los fármacos , Aorta Abdominal/efectos de los fármacos , Aorta Abdominal/metabolismo , Aorta Torácica/efectos de los fármacos , Aorta Torácica/metabolismo , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/genética , Inhibidores de la Ciclooxigenasa 2/farmacología , Inhibidores de la Ciclooxigenasa/farmacología , Endotelio Vascular/efectos de los fármacos , Técnicas In Vitro , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Especificidad de Órganos , Concentración Osmolar , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Ratas , Ratas WistarRESUMEN
Bradykinin (BK) is a vasorelaxant, algesic and inflammatory agent. Angiotensin II (AngII) is known to control vascular tone and promote growth, inflammation and artherogenesis. There is evidence for cross talking between BK and AngII receptors. Therefore, the effect of lack of kinin receptors was assessed in mice with genetic disruption of B(1) or B(2) and both receptors. Responsiveness of abdominal aortic rings to BK and AngII as well as the receptor gene expression of both peptides were analysed. Although no specific phenotype was displayed in the normotensive and healthy mice lacking the kinin receptors, a decreased expression level of the remaining kinin receptor mRNA was observed. AT(1) receptor mRNA level was also reduced, indicating that kinin receptors regulate AngII receptors. Downregulation of the receptors was well correlated with reduction in the reactivity of both agonists to induce contraction of aortic rings, but other signal regulations must be sought in these transgenic mice. We conclude that cross talk between kinin and AngII receptors occurs in mouse abdominal aorta and that both peptides may regulate the initiation and progression of important pathophysiological processes, such as hypertension and inflammation.
Asunto(s)
Aorta Abdominal/metabolismo , Receptores de Angiotensina/metabolismo , Angiotensina II/farmacología , Animales , Aorta Abdominal/efectos de los fármacos , Bradiquinina/farmacología , Imidazoles/antagonistas & inhibidores , Cininas/farmacología , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , NG-Nitroarginina Metil Éster/farmacología , Reacción en Cadena de la Polimerasa , Piridinas/antagonistas & inhibidores , Receptor de Bradiquinina B1/genética , Receptor de Bradiquinina B1/metabolismo , Receptor de Bradiquinina B2/genética , Receptor de Bradiquinina B2/metabolismo , Receptores de Angiotensina/genética , Vasodilatadores/farmacologíaRESUMEN
In this study, nonenzymatic glycosylation was assessed in aorta extracellular matrix (ECM) from nonobese diabetic (NOD) mice, using nitroblue tetrazolium (NBT). Molecular and structural changes were investigated in elastic lamellae and collagen fibers of diabetic mice aortas after staining with dansyl chloride and anilinonaphthalene sulfonate (ANS). Alterations in arterial autofluorescence and birefringence of collagen fibers were investigated in unstained aortas. Proliferation of smooth muscle cells (SMC) was also investigated by Feulgen reaction staining assessed by confocal microscopy and image analysis. Assessment of nonenzymatic glycosylation demonstrated glycosylation products in the aorta ECM of NOD mice. Elastic lamellae and collagen fibers from NOD mouse aortas presented less intense fluorescence after staining with dansyl chloride and ANS when compared to aortas of control nondiabetic mice. However, unstained NOD aortas showed more intense autofluorescence when compared to controls. Birefringence analysis suggests alterations in the higher molecular packing of the arterial collagen fibers in NOD aortas. In aortas stained by Feulgen reaction, no evidence of SMC proliferation was observed in diabetic aortas.
Asunto(s)
Aorta Abdominal/patología , Diabetes Mellitus Tipo 1/patología , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos , Animales , Aorta Abdominal/metabolismo , Birrefringencia , Proliferación Celular , Colágeno/química , Colágeno/ultraestructura , Compuestos de Dansilo/química , Diabetes Mellitus Tipo 1/metabolismo , Tejido Elástico/química , Tejido Elástico/patología , Glicosilación , Indicadores y Reactivos/química , Ratones , Ratones Endogámicos NOD , Músculo Liso Vascular/patología , Nitroazul de Tetrazolio/química , Coloración y EtiquetadoRESUMEN
1. In humans, two of the principal characteristics of vascular ageing are arterial wall calcification and decreased arterial distensibility, which induce organ damage. To amplify arterial calcium accumulation in laboratory animals, it is necessary to use an overdose of vitamin D(3). 2. The aim of the present study was to assess the impact of arterial calcium overload on renal function. 3. Adult male Wistar rats were randomly divided into two groups: control and treated rats. Treated rats were injected 10 days before the experiment with a single dose of vitamin D(3) (300 000 IU/kg, i.m.). 4. Treated rats showed a decrease in renal blood flow and glomerular filtration rate. Tubular parameters were not modified under basal conditions. In contrast, a statistically significant increase in the fractional excretion of Na, K, Ca and H(2)O were observed in treated rats after the acute increment of sodium distal delivery, suggesting that the reabsorptive capacity of the thick ascending limb may be altered in treated rats. 5. Thus, Na(+)/K(+)-ATPase activity was evaluated in homogenates from renal cortex and medulla. Rats with arterial calcinosis presented a diminished activity of Na(+)/K(+)-ATPase in medulla homogenates. 6. An increment in the abundance of the Na-K-2Cl cotransporter (NKCC2) was observed in renal medulla homogenates from treated rats. It is suggested that this may compensate for the inefficiency of Na(+)/K(+)-ATPase under basal conditions but, in the presence of acute distal sodium overload, the increment in NKCC2 abundance may not be sufficient to compensate for the decrease in Na(+)/K(+)-ATPase activity. 7. In summary, in our experimental model of arterial calcinosis, renal function is impaired, presenting a vascular compromise and altered function of the medullar thick ascending limb that becomes evident in the presence of acute high distal sodium delivery.
Asunto(s)
Aorta Abdominal/metabolismo , Calcinosis/metabolismo , Enfermedades Renales/metabolismo , Túbulos Renales Distales/metabolismo , Arteria Renal/metabolismo , Animales , Calcinosis/tratamiento farmacológico , Colecalciferol/uso terapéutico , Enfermedades Renales/tratamiento farmacológico , Túbulos Renales Distales/irrigación sanguínea , Masculino , Ratas , Ratas WistarRESUMEN
In vascular smooth muscle, calcium overload is a highly pathogenic event, which increases with advancing age. An increase in the calcium content of arterial wall may be produced in rats by treatment with vitamin D3. The aim of this study was to evaluate the renal clearance of sulfanilamide (a model organic anion, preferentially eliminated by the kidneys) and other parameters of global renal function in rats with arterial calcinosis. Arterial calcinosis was produced in adult rats by means of a single dose of vitamin D3 (300,000 UI/kg bw, i.m.) 5 days before the experiment. Treated rats showed a large increase in calcium content of aortic tissue and an increase in systolic arterial pressure. No modifications were observed in plasma calcium levels and in plasma lipid profiles. Statistically significant decrements were observed in renal clearance of sulfanilamide, in renal blood flow, in fractional excretion of sodium and potassium. A slight decrease, not statistically different, was observed in the glomerular filtration rate. Rats with arterial calcinosis also showed an increment of total calcium levels in renal tissue, in fractional excretion of calcium and in the expression of organic anion transporter 1 (OAT1). Histological studies revealed tubular alterations. In summary, modifications in hemodynamics and tubular parameters are early manifestations of nephropathy in rats with arterial calcinosis, some of which may account for the changes observed in organic anions renal depuration. It is important to mention that the decrease in clearance of organic anions were seen in spite of the increase in expression of OAT1.
Asunto(s)
Enfermedades de la Aorta/metabolismo , Calcinosis/metabolismo , Enfermedades Renales/metabolismo , Animales , Aorta Abdominal/metabolismo , Enfermedades de la Aorta/inducido químicamente , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Calcinosis/inducido químicamente , Calcio/metabolismo , Colecalciferol/efectos adversos , Modelos Animales de Enfermedad , Tasa de Filtración Glomerular/efectos de los fármacos , Tasa de Filtración Glomerular/fisiología , Enfermedades Renales/fisiopatología , Pruebas de Función Renal , Masculino , Proteína 1 de Transporte de Anión Orgánico/biosíntesis , Ensayos Clínicos Controlados Aleatorios como Asunto , Ratas , Ratas Wistar , Circulación Renal/efectos de los fármacos , Circulación Renal/fisiología , Sulfanilamida , Sulfanilamidas/metabolismo , Sulfanilamidas/farmacología , Sístole/efectos de los fármacos , Sístole/fisiología , Factores de TiempoRESUMEN
We examined the presence of estrogen receptors (ER) in vascular mast cells and a possible genomic effect of estrogens on the expression of mast cell (MC) mediators such as chymase, TNF alpha, NOS and IL-10, which are known to affect the course of atherosclerosis. Immunocytochemical detection of mast cell tryptase and the co-localization of ERs in MCs from abdominal aortic vessels from 10 fertile woman, 10 postmenopausal women and 15 men was performed. The genomic expression of IL-10, TNF alpha, and NOS was analyzed by RT-PCR and chymase activity by spectrophotometry after 24 h incubation with 17-beta estradiol (0.2-0.5 ng/mL) in rat purified peritoneal MCs. A similar number of MCs were found in both intima and adventitia layers from men, and fertile and postmenopausal women, while ERs were detected only in the arterial walls from fertile women. The mRNA expressions of IL-10 and TNF alpha, as well as chymase activity, were not affected. A moderate increment of NO and both NOS, and a reduction in TNF alpha cytotoxicity was observed after incubating peritoneal MCs with 17-beta estradiol at a concentration of 0.5 ng/mL. Taken together, these results indicate that vascular MCs express ERs. The data demonstrate that estrogens can directly modify vascular MC activity. This is a novel mechanism of synergistic cooperation for the protective role of estrogens in the genesis of atherosclerosis.
Asunto(s)
Arterias/metabolismo , Mastocitos/metabolismo , Receptores de Estrógenos/metabolismo , Animales , Aorta Abdominal/citología , Aorta Abdominal/metabolismo , Arterias/citología , Femenino , Humanos , Interleucina-10/genética , Masculino , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo II , Óxido Nítrico Sintasa de Tipo III , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
We examined the presence of estrogen receptors (ER) in vascular mast cells and a possible genomic effect of estrogens on the expression of mast cell (MC) mediators such as chymase, TNF alpha, NOS and IL-10, which are known to affect the course of atherosclerosis. Immunocytochemical detection of mast cell tryptase and the co-localization of ERs in MCs from abdominal aortic vessels from 10 fertile woman, 10 postmenopausal women and 15 men was performed. The genomic expression of IL-10, TNF alpha, and NOS was analyzed by RT-PCR and chymase activity by spectrophotometry after 24 h incubation with 17-beta estradiol (0.2-0.5 ng/mL) in rat purified peritoneal MCs. A similar number of MCs were found in both intima and adventitia layers from men, and fertile and postmenopausal women, while ERs were detected only in the arterial walls from fertile women. The mRNA expressions of IL-10 and TNF alpha, as well as chymase activity, were not affected. A moderate increment of NO and both NOS, and a reduction in TNF alpha cytotoxicity was observed after incubating peritoneal MCs with 17-beta estradiol at a concentration of 0.5 ng/mL. Taken together, these results indicate that vascular MCs express ERs. The data demonstrate that estrogens can directly modify vascular MC activity. This is a novel mechanism of synergistic cooperation for the protective role of estrogens in the genesis of atherosclerosis.(AU)
Asunto(s)
Humanos , Animales , Masculino , Femenino , Ratas , RESEARCH SUPPORT, NON-U.S. GOVT , Arterias/metabolismo , Mastocitos/metabolismo , Receptores de Estrógenos/metabolismo , Aorta Abdominal/citología , Aorta Abdominal/metabolismo , Arterias/citología , Interleucina-10/genética , Óxido Nítrico Sintasa/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
1. Ageing induces calcium accumulation in the vascular system. The simplest experimental way of producing high degrees of arterial calcium overload is by administration of an overdose of vitamin D(3) to rats. The aim of the present study was to evaluate the pharmacokinetics of organic anions in rats with arterial calcinosis induced by an overdose of vitamin D(3). 2. We used bromosulfophthalein (BSP) and sulfanilamide (SA) as models of organic anions with preferential biliary and renal excretion, respectively. 3. Increases in the clearance and elimination rate constant of BSP were observed in treated rats. The clearance and the elimination rate constant for SA were also increased in rats with arterial calcinosis. 4. Variations in arterial hepatic blood flow, aspartate aminotransferase activity and liver calcium accumulation were not observed in treated rats. In contrast, treated rats had a lower renal blood flow and increased renal calcium levels. 5. In summary, rats with arterial calcinosis showed an increase in total body clearance of both BSP and SA, probably associated with modifications in their metabolism and/or in organ extraction. Alterations to hepatic and renal blood flow do not account for these phenomena.
Asunto(s)
Aniones/farmacocinética , Arteriopatías Oclusivas/sangre , Calcinosis/sangre , Fenolsulfonftaleína/análogos & derivados , Fenolsulfonftaleína/farmacocinética , Sulfanilamidas/farmacocinética , Animales , Aniones/sangre , Aorta Abdominal/metabolismo , Aorta Abdominal/patología , Calcinosis/inducido químicamente , Colecalciferol/efectos adversos , Riñón/metabolismo , Riñón/patología , Hígado/metabolismo , Hígado/patología , Masculino , Ratas , Ratas Wistar , Sulfanilamida , Sulfanilamidas/sangreRESUMEN
Because shikimic acid is the key intermediate in the shikimate pathway in plants and microorganisms, shikimic acid and its derivatives have been described as herbicides and anti-microbial agents. Triacetylshikimic acid (TSA) is an acetylate derivative of shikimic acid. The possible anti-platelet activity and anti-thrombotic efficacy of TSA were evaluated and its effect on arachidonic acid (AA) metabolism and second messengers including cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) was evaluated. After oral pretreatment with TSA, adenosine diphosphate (ADP)-, collagen-, and AA-induced rat platelet aggregation was inhibited ex vivo in a dose-dependent manner. In an arteriovenous-shunt thrombosis model, oral administration of TSA resulted in a dose-dependent inhibition of thrombus growth. TSA markedly increased the cAMP level and showed no effect on the cGMP level in rat platelets. Also, no significant changes in ADP-induced thromboxane B2 formation in rat platelets or 6-keto-prostaglandin F 1alpha production from the abdominal aorta were observed after oral administration of low and medium doses of TSA (12.5 and 50 mg/kg). Additionally, prothrombin time, activated partial thromboplastin time, and thrombin time were unchanged at effective anti-platelet doses of TSA. These results demonstrate that TSA exerts oral anti-platelet and anti-thrombotic efficacy without perturbation of systemic hemostasis in rats, which was partially concerned with the elevation of cAMP in platelets.
Asunto(s)
Inhibidores de Agregación Plaquetaria/farmacología , Ácido Shikímico/análogos & derivados , Ácido Shikímico/farmacología , Trombosis/prevención & control , 6-Cetoprostaglandina F1 alfa/metabolismo , Animales , Aorta Abdominal/metabolismo , Aspirina/farmacología , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , AMP Cíclico/sangre , GMP Cíclico/sangre , Masculino , Tiempo de Tromboplastina Parcial , Tiempo de Protrombina , Radioinmunoensayo , Ratas , Ratas Wistar , Tiempo de Trombina , Trombosis/etiología , Tromboxano B2/sangreRESUMEN
The pharmacokinetics of methyldopa (12.5, 25 and 50 mg kg(-1), i.p.) was studied in anesthetized sham-operated (SO) and abdominal aorta-coarctated (ACo) rats using a microdialysis technique. A non-linear relationship between the area under the curve (AUC) and dose was observed in SO rats. However, in ACo rats the AUC showed a proportional increase with dose. Abdominal aortic coarctation produced significant differences in the estimates of clearance (Cl) and the elimination rate constant from the dialysate (K(ed)) after the administration of 50 mg kg(-1)of methyldopa (K(ed)SO, 0.31 +/- 0.09; ACo, 0.66 +/- 0.09(*)h(-1): Cl SO, 30.8 +/- 10.1; ACo, 78.6 +/- 13.3(*)mlkg(-1)min(-1);n= 6,(*)P< 0.05 vs SO). In conclusion, this study, by using a microdialysis technique, suggests that abdominal aortic coarctation seems to produce changes in the pharmacokinetics of methyldopa in rats.
Asunto(s)
Antihipertensivos/farmacocinética , Aorta Abdominal/metabolismo , Metildopa/farmacocinética , Animales , Antihipertensivos/sangre , Aorta Abdominal/lesiones , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Masculino , Metildopa/sangre , Microdiálisis/métodos , Ratas , Ratas WistarRESUMEN
Hig levels of circulating atrial natriuretic factor (ANF) have been reported in several physiopathologic conditions like hypertension, heart and renal failure, pregnancy and high sodium intake. Nevertheless, neither relationships with water-sodium space regulation nor the role of an ANF vascular relaxant effect have been yet defined. The aim of present experiments was to characterize the contribution of circulating ANF and its vascular relaxing effects in the two kidney-two clip (2K2C) experimental model of renovascular hypertension. Complementary, plasma metabolites nitrite/nitrate of nitric oxide (NO) was examined because of mediation for both (NO an ANF) through cGMP. Three results showed (two-four weeks after surgery): indirect systolic blood pressure (mmHg), 186 +/- 4 in HT and 122 +/- 1 in SH (p < 0.001); a significant increase of plasma ANF (fmol/ml) in HT (n = 7, 1221 +/- 253) vs. SH (n = 9, 476 +/- 82; p < 0.02). Nitrate/nitrite plasma concentrations (mumol/l) were mpt different between SH and. The relaxant effect of ANF (10(-9), 10(-8) and 10(-7) M) on phenylephrine (3,5 x 10(-6) M) contracted rings from HT rats was smaller than SH rats (10(-8) M, p < 0.05). Contractions to phorbol 12, 13-dibutyrate (seven weeks after surgery) were significantly higher in rings from HT rats (p < 0.001). We conclude: 1) in addition to decreased granularity in atrial myocardiocytes, high circulating values of ANF here described suggest an increased turnover of the peptide in 2K2C hypertensive rats; 2) lower significant vascular relaxant effects in HT rats would indicate down regulation of ANF receptors in this model; the latter would derive from high plasma ANF concentration and, tentatively, because of greater activity of protein kinase C in the vascular wall; 39 similar values of plasma nitrite/nitrate in SH and HT rats would indicate a comparable NO circulating availability in both groups.
Asunto(s)
Factor Natriurético Atrial/sangre , Hipertensión Renovascular/metabolismo , Riñón/metabolismo , Óxido Nítrico/sangre , Animales , Aorta Abdominal/metabolismo , Factor Natriurético Atrial/metabolismo , Presión Sanguínea , Hipertensión Renovascular/sangre , Masculino , Músculo Liso Vascular/metabolismo , Nitratos/sangre , Nitratos/metabolismo , Óxido Nítrico/metabolismo , Nitritos/sangre , Nitritos/metabolismo , Ratas , Ratas WistarRESUMEN
D-002 is a mixture of higher aliphatic primary alcohol isolated from bees wax (Apis mellifera) with effective antiulcer effects demonstrated in different experimental models. Oral toxicity of D-002 (5-5000 mg/kg) was evaluated in sub-acute (14 days), subchronic (90 days) and chronic (1 year) studies in Sprague-Dawley rats from both sexes. There was no treatment-related toxicity. Thus, effects on body weight, food consumption, clinical observations, blood parameters, organ weight ratios and histopathological findings were similar in control and treated groups. These short and long-term studies support a wide safety margin for this product.