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1.
Zhonghua Gan Zang Bing Za Zhi ; 31(6): 608-613, 2023 Jun 20.
Artículo en Chino | MEDLINE | ID: mdl-37400385

RESUMEN

Objective: To investigate the clinical efficacy of entecavir combined with Biejiajian pills and its influence on TCM syndrome scores during the treatment of chronic hepatitis B with hepatic fibrosis and blood stasis syndrome by prospective, randomized and controlled study. Methods: Patients with chronic hepatitis B with hepatic fibrosis and blood stasis syndrome were selected as the research subjects and randomly divided into a treatment group and a control group. Entecavir plus Biejiajian pills or entecavir plus a simulant of Biejiajian pills were given for 48 weeks. The changes in liver stiffness measurement (LSM) and TCM syndrome scores before and after treatment were compared between the two groups to analyze the correlation. The data between groups were analyzed by t-test/Wilcoxon rank sum test or χ(2) test. Pearson correlation coefficient was used to analyze the correlation between TCM syndrome scores and LSM values. Results: After 48 weeks of treatment, the LSM values of the two groups were significantly lower than those of the baseline (P < 0.001), liver fibrosis was significantly improved, and the LSM values of the treatment group were lower than those of the control group [(8.67 ± 4.60) kPa and (10.13 ± 4.43) kPa, t = -2.011, P = 0.049]. After 48 weeks of treatment, the TCM syndrome scores of the two groups were significantly reduced compared with the baseline (P < 0.001), and the clinical symptoms were significantly relieved, and the total effective rates of the improvement of the TCM syndrome scores in the two groups were 74.19% and 72.97%, respectively, but the differences between the groups were not statistically significant (χ(2) = 0.013, P = 0.910). Correlation analysis showed that there was no obvious trend between TCM syndrome scores and LSM values. There were no serious adverse reactions associated with the drug during the observation period of this study. Conclusion: Based on antiviral treatment with entecavir, regardless of whether it is combined with the Biejiajian pill, it can effectively reduce the LSM value, improve liver fibrosis, reduce TCM syndrome scores, and alleviate symptoms in patients with chronic hepatitis B with liver fibrosis and blood stasis syndrome. Compared with entecavir alone, the combined Biejia pill has greater efficacy in improving liver fibrosis and a favorable safety profile, meriting its implementation and widespread application.


Asunto(s)
Hepatitis B Crónica , Humanos , Antivirales/uso terapéutico , Hepatitis B Crónica/tratamiento farmacológico , Cirrosis Hepática/tratamiento farmacológico , Estudios Prospectivos , Resultado del Tratamiento
4.
Genet Mol Res ; 14(3): 9103-8, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-26345842

RESUMEN

Highly conserved endogenous non-coding microRNAs (miRNAs) play important roles in plants and animals by silencing genes via destruction or blocking of translation of homologous mRNA. Sugar beet, Beta vulgaris, is one of the most important sugar crops in China, with properties that include wide adaptability and strong tolerance to salinity and impoverished soils. Seedlings of B. vulgaris can grow in soils containing up to 0.6% salt; it is important to understand the molecular mechanisms of salt tolerance to enrich genetic resources for breeding salt-tolerant sugar beets. Here, we report 13 mature miRNAs from 12 families, predicted using an in silico approach from 29,857 expressed sequence tags and 279,223 genome survey sequences. The psRNATarget server predicted 25 target genes for the 13 miRNAs. Most of the target genes appeared to encode transcription factors or were involved in metabolism, signal transduction, stress response, growth, and development. These results improve our understanding of the molecular mechanisms of miRNA in beet and may aid in the development of novel and precise techniques for understanding post-transcriptional gene-silencing mechanisms in response to stress tolerance.


Asunto(s)
Beta vulgaris/genética , Etiquetas de Secuencia Expresada , MicroARNs/genética , Beta vulgaris/crecimiento & desarrollo , China , Biología Computacional , Regulación de la Expresión Génica de las Plantas , MicroARNs/aislamiento & purificación , ARN Mensajero/genética , Salinidad , Tolerancia a la Sal/genética
5.
Genet Mol Res ; 14(2): 3149-59, 2015 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-25966080

RESUMEN

We investigated the effect of p38MAPK/AP-1 (activator protein-1) signaling on the apoptosis of osteoblasts induced by high glucose. A lentivirus vector of small hairpin RNA (shRNA) targeting p38MAPK was constructed in vitro. Osteoblasts MC3T3-E1 cultured in vitro were treated with vehicle, high glucose, p38MAPK-shRNA transfection, p38MAPK inhibitor, and unrelated shRNA transfection. Apoptosis, protein levels of p38MAPK, and activities of AP-1 in MC3T3-E1 osteoblasts were measured using TUNEL and flow cytometry, Western blot analysis, and an electrophoretic mobility shift assay. Compared with the vehicle group, high glucose induced apoptosis of MC3T3-E1 osteoblasts and activated p38MAPK and AP-1. p38MAPK-shRNA transfection blocked the effect of high glucose stimulation, and the p38MAPK inhibitor showed similar effects as those observed in p38MAPK transfection. Unrelated shRNA had no effect on these changes in MC3T3-E1 osteoblasts induced by high glucose. Therefore, our results suggest that p38MAPK-shRNA reduce apoptosis of MC3T3-E1 osteoblasts induced by high glucose by inhibiting the p38MAPK-AP-1 signaling pathway.


Asunto(s)
Apoptosis/efectos de los fármacos , Glucosa/farmacología , Osteoblastos/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Factor de Transcripción AP-1/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Western Blotting , Línea Celular , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Citometría de Flujo , Expresión Génica/efectos de los fármacos , Imidazoles/farmacología , Etiquetado Corte-Fin in Situ , Ratones , Osteoblastos/citología , Osteoblastos/metabolismo , Unión Proteica/efectos de los fármacos , Piridinas/farmacología , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/genética
6.
Eur Respir Rev ; 18(113): 186-9, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20956142

RESUMEN

Mucormycosis is a rare opportunistic infection usually associated with immunosuppression, diabetes mellitus or haematological malignancy. Herein, we report an unusual case of mucormycosis in a 46-yr-old male patient with diabetes presenting with an endotracheal mass obstructing the trachea and cartilage damage. Histological examination of the bronchoscopy biopsy specimens revealed invasive mucormycosis. The patient was treated with intravenous amphotericin B followed by removal of the lesion via bronchoscopy.


Asunto(s)
Anfotericina B/uso terapéutico , Cartílago , Mucormicosis/diagnóstico , Mucormicosis/tratamiento farmacológico , Enfermedades de la Tráquea , Antifúngicos/uso terapéutico , Biopsia , Broncoscopía , Cartílago/diagnóstico por imagen , Cartílago/microbiología , Cartílago/patología , Disnea/diagnóstico , Disnea/tratamiento farmacológico , Disnea/microbiología , Humanos , Masculino , Persona de Mediana Edad , Mucormicosis/inmunología , Necrosis , Radiografía , Tráquea/diagnóstico por imagen , Tráquea/microbiología , Tráquea/patología , Enfermedades de la Tráquea/diagnóstico , Enfermedades de la Tráquea/tratamiento farmacológico , Enfermedades de la Tráquea/microbiología
7.
Hum Gene Ther ; 8(6): 755-64, 1997 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-9113515

RESUMEN

The intestine is proposed to be an attractive target site for somatic gene therapy due to a large mass of proliferating tissue and stem cells in the crypts. Previous studies using a retroviral vector have shown that a reporter gene, bacterial beta-galactosidase (beta-Gal), can be transferred and expressed in the small intestinal epithelial cell. However, transduction efficiency is relatively low in rat and mice intestines. In the present study, we employed an E1-deleted adenoviral vector (which encodes the beta-Gal gene) to investigate the feasibility of gene transfer into rat small intestinal epithelial cell lines and small intestines in male Sprague-Dawley rats. In in vitro studies, expression of AdCMV beta gal was quantitatively measured in IEC-6 and IEC-18 cell cultures using X-Gal histochemistry and chemiluminescent reporter gene assays. The results indicate that AdCMV beta gal can be efficiently transferred into intestinal epithelial cell lines and transgene expression is virus concentration dependent. In in vivo studies, a 5F intestinal feeding tube was used to deliver the vector to the duodenal segment of the rat. Expression of AdCMV beta gal was primarily localized to the epithelium of the intestinal tract. Transduction efficiency of the transgene was seen in the duodenum, jejunum, ileum, and, to a lesser extent, the colon. Moreover, following a single or secondary administration of recombinant adenovirus, efficient expression of AdCMV beta gal in the intestinal tract peaked at 3 days and decreased by 7 and 14 days. No antiadenoviral antibody response was detected in the serum after a single or secondary challenge with this virus. These findings demonstrate that an E1-deleted adenoviral vector, when administered through an oral-duodenal tube, transfers genetic material more successfully in the intestinal epithelium in the small intestine when compared to the large intestine. A single or secondary challenge with adenoviral vector does not cause enhanced host immune responses to this virus. It suggests that successful gene transduction by the repeat administration of the adenoviral vector makes it an alternative candidate for gene therapy applications in intestinal diseases and metabolic deficiencies.


Asunto(s)
Adenoviridae , Técnicas de Transferencia de Gen , Vectores Genéticos , Mucosa Intestinal/metabolismo , Proteínas E1 de Adenovirus/genética , Animales , Células Cultivadas , Terapia Genética/métodos , Intestino Delgado/metabolismo , Mediciones Luminiscentes , Masculino , Ratones , Ratas , Ratas Sprague-Dawley , Transgenes , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo
8.
Am J Physiol ; 271(6 Pt 1): L924-31, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8997262

RESUMEN

The effects of the vascular selective nonsulfonylurea guanidine ATP-sensitive K+ (KATP+) channel-blocking agent U-37883A on vasodilator and vasoconstrictor responses were investigated in the pulmonary and hindlimb vascular beds of the cat. Under elevated tone conditions, both U-37883A and the sulfonylurea KATP+ antagonist, glibenclamide, attenuated pulmonary vasodilator responses to the KATP+ channel openers without altering responses to vasodilator agents that are reported to act by KATP(+)-independent mechanisms. However, under low resting-tone conditions, U-37883A enhanced pulmonary vasoconstrictor responses to the thromboxane mimic U-46619 and to prostaglandin (PG) F2 alpha and PGD2, whereas glibenclamide antagonized responses to U-46619 and the vasoconstrictor PG. In the hindlimb vascular bed, U-37883A and glibenclamide had no effects on responses to U-46619 in doses that inhibited vasodilator responses to the KATP+ channel opener levcromakalim. U-37883A and glibenclamide had no significant effect on baseline tone in the pulmonary or hindlimb vascular beds, and neither U-37883A nor glibenclamide altered pulmonary vasodilator responses to PGE1. The results of the present investigation show that U-37883A and glibenclamide, agents that are used in the study of vascular smooth muscle KATP+ channel mechanisms and attenuate vasodilator responses to the KATP+ channel openers, have pronounced effects on thromboxane/PG receptor-mediated vasoconstrictor responses in the pulmonary vascular bed of the cat.


Asunto(s)
Adamantano/análogos & derivados , Vasos Sanguíneos/efectos de los fármacos , Extremidades/irrigación sanguínea , Morfolinas/farmacología , Bloqueadores de los Canales de Potasio , Circulación Pulmonar/efectos de los fármacos , Adamantano/farmacología , Animales , Vasos Sanguíneos/metabolismo , Gatos , Femenino , Gliburida/farmacología , Masculino , Vasodilatación/efectos de los fármacos
9.
Ann N Y Acad Sci ; 805: 429-41; discussion 442, 1996 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-8993422

RESUMEN

Responses to pituitary adenylate cyclase polypeptide (PACAP)-27, PACAP-38, and vasoactive intestinal peptide (VIP) were compared in the peripheral and pulmonary vascular beds of the cat and in the isolated perfused neonatal pig heart. Intravenous injections of PACAP-27 and PACAP-38 produced biphasic changes in systemic arterial pressure whereas iv injections of VIP caused only decreases in arterial pressure. When blood flow to the hind limb and mesenteric vascular beds was maintained constant, PACAP-27 and PACAP-38 caused dose-related biphasic changes in perfusion pressure, whereas VIP only decreased perfusion pressure. PACAP-27 was approximately threefold more potent than PACAP-38, and the pressor component of the biphasic response was blocked by alpha-adrenergic antagonists and adrenalectomy. PACAP-27, PACAP-38, and VIP produced decreases in pulmonary vascular resistance, and all three peptides had significant vasodilator activity in the isolated perfused neonatal pig heart. Although all three peptides decreased coronary vascular resistance, only PACAP-27 and PACAP-38 increased left ventricular contractility, with PACAP-27 approaching isoproterenol in potency. The results of these experiments show that PACAP-27, PACAP-38, and VIP have significant effects on vasomotor tone that depend on the vascular bed studied and the contribution of adrenal catecholamines.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Corazón/fisiología , Hemodinámica/efectos de los fármacos , Neuropéptidos/farmacología , Péptido Intestinal Vasoactivo/farmacología , Secuencia de Aminoácidos , Animales , Animales Recién Nacidos , Gatos , Femenino , Corazón/efectos de los fármacos , Miembro Posterior/irrigación sanguínea , Técnicas In Vitro , Masculino , Arteria Mesentérica Superior/efectos de los fármacos , Arteria Mesentérica Superior/fisiología , Datos de Secuencia Molecular , Músculo Esquelético/irrigación sanguínea , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/fisiología , Neuropéptidos/química , Neurotransmisores/farmacología , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , Circulación Pulmonar/efectos de los fármacos , Porcinos , Resistencia Vascular/efectos de los fármacos , Péptido Intestinal Vasoactivo/química
10.
Am J Physiol ; 270(1 Pt 2): H200-7, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8769752

RESUMEN

Adenosine produces tone-dependent pulmonary vascular responses; however, the adenosine receptor subtype mediating these responses is unknown. In the present study, the adenosine receptor subtypes mediating tone-dependent responses were investigated, Intralobar injections of adenosine,ATP, and analogues under low-tone conditions caused dose-related increases in lobar arterial pressure; the order of potency was alpha,beta-methylene ATP (alpha,beta-metATP) > N6-cyclopentyladenosine (CPA) > ATP > adenosine. Under low-tone conditions, pressor responses to adenosine, ATP, and CPA, an adenosine A1-receptor agonist, were reduced by KW-3902, an adenosine A1-receptor antagonist, whereas KW-3902 and meclofenamate had no effect on responses to alpha,beta-metATP, norepinephrine, serotonin, or angiotensin II. Under elevated-tone conditions, injections of adenosine, ATP, and analogues caused dose-related decreases in lobar arterial pressure, and adenosine was 10-fold less potent than 5'-(N-cyclopropyl)-carboxamidoadenosine (CPCA), an A2-receptor agonist, and ATP. KF-17837, an A2-receptor antagonist, reduced vasodilator responses to adenosine and CPCA, whereas responses to ATP, isoproterenol, diethylamine-NO, lemakalim, and bradykinin were not changed. The vasodilator responses to adenosine were not attenuated by Nw-nitro-L-arginine benzyl ester, methylene blue, or U-37883A. These results suggest that vasoconstrictor responses to adenosine are mediated by A1 receptors and the release of vasoconstrictor prostanoids, and that, under elevated-tone conditions, vasodilator responses are mediated by A2 receptors but not the release of nitric oxide or the activation of guanylate cyclase or K+ATP channels.


Asunto(s)
Tono Muscular/fisiología , Músculo Liso Vascular/fisiología , Circulación Pulmonar/fisiología , Receptores Purinérgicos P1/fisiología , Adamantano/análogos & derivados , Adamantano/farmacología , Adenosina/farmacología , Adenosina Trifosfato/farmacología , Animales , Arginina/análogos & derivados , Arginina/farmacología , Gatos , Femenino , Masculino , Azul de Metileno/farmacología , Morfolinas/farmacología , Músculo Liso Vascular/efectos de los fármacos , Prostaglandina-Endoperóxido Sintasas/metabolismo , Circulación Pulmonar/efectos de los fármacos , Agonistas del Receptor Purinérgico P1 , Xantinas/farmacología
11.
Oncogene ; 11(4): 723-33, 1995 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-7651736

RESUMEN

We present evidence in favor of the position that some mutant p53 proteins retain the ability to trans-activate downstream genes through p53 DNA-binding consensus sequence (CS) homologies. We tested one cell line possessing high levels of mutant p53 and found that this mutant p53 is highly active in trans-activating one CS homology, moderately active in trans-activating a second sequence and inactive in modulating a third sequence. We tested a second cell line, also possessing high levels of mutant p53 and found the same pattern of activation. In addition we find that inter-motif distance [represented by N in RRRCWWGYYY(N)RRRCWWGYYY] is very important in determining the relative binding affinity of a given CS homology for wild-type or mutant p53. Our studies suggest that stereospecific alignment of the DNA-binding motifs within the CS may favor binding of wild-type p53 while misalignment may favor binding of mutant p53. Furthermore, we find that the maximum distances at which p53 DNA-binding CS homologies are functionally active vary for different sequences. Introduction of as few as 200 bp between one CS homology and the downstream TATA box can eliminate a 45-fold p53-mediated transactivation. We present evidence that the composition of the DNA which flanks a p53 DNA-binding consensus sequence may also modulate trans-activation.


Asunto(s)
Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Mutación , Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Línea Celular , Secuencia de Consenso , Cartilla de ADN , Células HeLa , Humanos , Luciferasas/análisis , Luciferasas/biosíntesis , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , TATA Box , Activación Transcripcional , Transfección , Células Tumorales Cultivadas
12.
Artículo en Inglés | MEDLINE | ID: mdl-8563372

RESUMEN

In this article, we present the prototype of the Multimedia Cardiac Angiogram Tool (MCAT). The MCAT provides capabilities for reviewing angiograms recorded at a cardiac catheterization laboratory. A doctor can use MCAT to annotate angiograms with audio, text, and graphics. He/she can selectively package the annotated multimedia angiograms into a document, save it as the record for the visit or use it for case presentations, or send it to another doctor over a network. MCAT streamlines data collection at a cath lab and is intended to improve the efficiency of communication and collaboration between doctors. This paper describes the design, implementation, and future directions of the prototype.


Asunto(s)
Angiografía Coronaria , Intensificación de Imagen Radiográfica , Sistemas de Computación , Computadores , Humanos , Registro Médico Coordinado , Sistemas de Registros Médicos Computarizados , Interpretación de Imagen Radiográfica Asistida por Computador , Telerradiología , Interfaz Usuario-Computador
13.
Life Sci ; 56(3): PL63-6, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7823766

RESUMEN

Responses to synthetic human adrenomedullin (ADM), a novel hypotensive peptide initially isolated from human pheochromocytoma cells, an ADM analog (ADM15-52), and a structurally related peptide, calcitonin gene-related peptide (CGRP), were compared in the pulmonary vascular bed of the cat and rat under constant flow conditions. When tone was increased with U46619, intraarterial injections of ADM (0.03-0.3 nmol), ADM15-52 (0.03-0.3 nmol), and of CGRP (0.03-0.3 nmol) caused dose-related decreases in pulmonary arterial perfusion pressure. When the relative vasodilator activity of the peptides was compared on a nmol basis, ADM was approximately 10-fold more potent in the cat than in the rat, whereas vasodilator responses to CGRP were very similar in both species. CGRP was slightly more potent than ADM in the rat, whereas ADM was slightly more potent than CGRP in the cat. ADM and ADM15-52 had similar pulmonary vasodilator activity in the cat, whereas the full sequence peptide was slightly more potent than ADM15-52 in the rat. The present data demonstrate that ADM has significant vasodilator activity in the pulmonary vascular beds of the cat and of the rat, and that the relative potency of the vasodilator effects of ADM and ADM15-52 are different in the two species.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/farmacología , Péptidos/farmacología , Circulación Pulmonar/efectos de los fármacos , Vasodilatadores/farmacología , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico , Adrenomedulina , Animales , Gatos , Femenino , Humanos , Masculino , Péptidos/química , Endoperóxidos de Prostaglandinas Sintéticos/farmacología , Ratas , Ratas Sprague-Dawley , Tromboxano A2/análogos & derivados , Tromboxano A2/farmacología , Vasoconstrictores/farmacología
14.
Circ Res ; 75(6): 1064-72, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7955144

RESUMEN

Responses to des-Arg9-bradykinin, a selective kinin B1 receptor agonist, were characterized in the pulmonary vascular bed of the intact-chest cat. Injections of des-Arg9-bradykinin into the perfused lobar artery under low-resting tone conditions caused dose-related increases in lobar arterial pressure; whereas in the same experiment under elevated tone conditions, injections of the B1 agonist caused dose-related decreases in lobar arterial pressure. Vasoconstrictor responses to des-Arg9-bradykinin under low-tone conditions and vasodilator responses under elevated-tone conditions were antagonized by des-Arg9,[Leu8]-bradykinin, a kinin B1 receptor antagonist, whereas responses under low- and high-tone conditions were not altered by Hoe 140, a kinin B2 receptor antagonist. Vasoconstrictor responses to des-Arg9-bradykinin under low-tone conditions were attenuated by phentolamine, prazosin, and reserpine but not by sodium meclofenamate, suggesting that release of catecholamines and activation of alpha-adrenergic receptors are involved. Pulmonary vasodilator responses under elevated-tone conditions were inhibited by N omega-nitro-L-arginine methyl ester, suggesting that des-Arg9-bradykinin stimulates the release of nitric oxide, whereas meclofenamate and U-37883A, a nonsulfonylurea ATP-sensitive K+ channel antagonist, did not alter vasodilator responses to the B1 receptor agonist. These results suggest that vasoconstrictor responses to des-Arg9-bradykinin under low-tone conditions are mediated by the activation of kinin B1 receptors, the release of catecholamines within the lung, and the activation of alpha-adrenergic receptors, whereas vasodilator responses under elevated tone conditions are mediated by activation of B1 receptors and the release of nitric oxide from the endothelium.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Bradiquinina/análogos & derivados , Pulmón/irrigación sanguínea , Pulmón/fisiología , Receptores de Bradiquinina/metabolismo , Animales , Bradiquinina/antagonistas & inhibidores , Bradiquinina/farmacología , Gatos , Femenino , Masculino , Circulación Pulmonar , Resistencia Vascular/efectos de los fármacos , Vasoconstricción/efectos de los fármacos , Vasodilatación/efectos de los fármacos
15.
Eur J Pharmacol ; 263(1-2): 133-40, 1994 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-7821344

RESUMEN

The effects of N omega-nitro-L-arginine methyl ester, an inhibitor of nitric oxide synthase; 6-anilino-5,8-quinolinedione (LY83583), an inhibitor of soluble guanylate cyclase; glybenclamide, a ATP-sensitive K+ channel blocking agent; and 5,7-dimethyl-2-ethyl-3-[[2'-(1H-tetrazol-5-yl)-[1,1']-biphenyl-4- yl]methyl]-3H-imidazo[4,5-b]pyridine (L158809), an angiotensin II type I receptor antagonist, on the response to ventilatory hypoxia were investigated in the isolated blood-perfused rat lung. Under conditions of controlled pulmonary blood flow, and constant left atrial pressure, injections of glybenclamide into the pulmonary arterial perfusion circuit significantly increased baseline pulmonary arterial perfusion pressure, whereas administration of N omega-nitro-L-arginine methyl ester produced smaller increases in baseline tone. Ventilatory hypoxia (3% O2-5% CO2-92% N2) significantly increased pulmonary arterial perfusion pressure and the response was reproducible with respect to time. Following administration of N omega-nitro-L-arginine methyl ester or LY83583, the response to hypoxia was significantly increased, whereas the response to hypoxia was not changed by glybenclamide or atropine. N omega-Nitro-L-arginine methyl ester also significantly enhanced pressor responses to angiotensin II, but had no effect on the pressor response to serotonin. When pulmonary vascular tone was increased with hypoxia, vasodilator responses to acetylcholine were inhibited by N omega-nitro-L-arginine methyl ester and vasodilator responses to levcromakalim were reduced by glybenclamide. In addition, L158809 did not alter the pressor response to hypoxia, whereas responses to angiotensin II were reduced in a selective manner.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Aminoquinolinas/farmacología , Arginina/análogos & derivados , Gliburida/farmacología , Imidazoles/farmacología , Circulación Pulmonar/efectos de los fármacos , Tetrazoles/farmacología , Antagonistas de Receptores de Angiotensina , Animales , Arginina/farmacología , Interacciones Farmacológicas , Hipoxia/tratamiento farmacológico , Masculino , NG-Nitroarginina Metil Éster , Óxido Nítrico/antagonistas & inhibidores , Ratas , Ratas Sprague-Dawley , Vasoconstricción/efectos de los fármacos
16.
Zhongguo Zhong Yao Za Zhi ; 19(9): 538-9, 574, 1994 Sep.
Artículo en Chino | MEDLINE | ID: mdl-7811365

RESUMEN

This paper deals with the effect of processing on Rheum palmatum. A HPLC method for the determination of rhein in the drug processed five different ways has been established. The method is simple, specific and accurate. The recovery is 98.52% and relative standard deviation.


Asunto(s)
Antraquinonas/análisis , Plantas Medicinales , Rheum/química , Cromatografía Líquida de Alta Presión , Calor , Tecnología Farmacéutica
17.
Eur J Pharmacol ; 261(1-2): 223-7, 1994 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-8001649

RESUMEN

Responses to angiotensin IV were investigated and compared with responses to angiotensin II in the pulmonary vascular bed of the intact-chest cat under constant flow conditions. Under low resting tone conditions, intralobar injections of angiotensin IV caused dose-related increases in lobar arterial pressure. Angiotensin II also increased lobar arterial pressure and was 100 fold more potent than angiotensin IV. Dose-response curves for both peptides were parallel, and the time-to-peak increase in lobar arterial pressure in response to angiotensin IV and angiotensin II was similar whereas the duration of the response to angiotensin IV was significantly shorter. Following administration of the angiotensin receptor subtype 1 (AT1) antagonist, DuP 532 (2-n-butyl-4-chloro-5-hydroxymethyl-1-[(2'-(1H-tetrazol-5-yl)biphe nyl-4- yl)-methyl]imidazole), responses to angiotensin IV and angiotensin II were reduced in a similar manner, whereas pulmonary pressor responses to serotonin were not altered. In contrast to the inhibitory effects of the angiotensin AT1 receptor antagonist, administration of PD 123,319 ((S)-1-[[4-(dimethylamino)-3-methyl-phenyl]methyl-5-(diphenylacetyl++ +)- 4,5,6,7-tetrahydro-1H-imidazol[4,5-c]pyridine-6-carboxylic acid), an angiotensin AT2 receptor antagonist, did not change responses to angiotensin II and angiotensin IV. The results of the present study demonstrate that angiotensin IV has significant vasoconstrictor activity in the pulmonary vascular bed, and suggest that pressor responses to angiotensin IV are mediated by the activation of angiotensin AT1 receptors. These data indicate that angiotensin IV is 100-fold less potent than angiotensin II and suggest that the hexapeptide may have a lower apparent affinity for the angiotensin AT1 receptor than does angiotensin II in the pulmonary vascular bed of the cat.


Asunto(s)
Angiotensina II/análogos & derivados , Circulación Pulmonar/efectos de los fármacos , Angiotensina I/farmacología , Angiotensina II/antagonistas & inhibidores , Angiotensina II/farmacología , Antagonistas de Receptores de Angiotensina , Animales , Análisis de los Gases de la Sangre , Presión Sanguínea/efectos de los fármacos , Gatos , Relación Dosis-Respuesta a Droga , Femenino , Imidazoles/farmacología , Masculino , Fragmentos de Péptidos/farmacología , Piridinas/farmacología , Tetrazoles/farmacología , Resistencia Vascular/efectos de los fármacos
18.
Am J Physiol ; 266(6 Pt 2): H2247-55, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8023987

RESUMEN

Pulmonary vascular responses to angiotensin (ANG) peptides were investigated in the intact-chest cat under conditions of controlled blood flow and constant left atrial pressure. Intralobar injections of ANG I, II, and III caused dose-related increases in lobar arterial pressure, whereas ANG (1-7) and ANG (3-8) (ANG IV) had modest pressor activity. ANG I, II, and III had similar activity and were more potent than norepinephrine and ANG (1-7) and ANG IV but less potent than the thromboxane A2 mimic, U-46619, in increasing lobar arterial pressure. The time course of responses to ANG I, II, and III was similar, and after administration of ANG receptor antagonists, DuP 532 and L-158,809, responses to ANG I, II, and III was reduced, whereas responses to norepinephrine, serotonin, and U-46619 were not altered. After administration of the ANG-converting-enzyme inhibitor, captopril, responses to ANG I were reduced. The converting-enzyme inhibitor enhanced pressor responses to ANG II and III but did not alter responses to norepinephrine, U-46619, or serotonin. Moreover, under elevated-tone conditions, pulmonary vasodilator responses to bradykinin were increased following administration of captopril, whereas vasodilator responses to acetylcholine and nitrovasodilators were not altered. These results demonstrate that ANG I, II, and III have similar pulmonary pressor activity and that responses are mediated by ANG II type 1 receptors. Pressor responses to ANG I are reduced, whereas vasodilator responses to bradykinin are enhanced by captopril.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Angiotensina III/farmacología , Angiotensina II/farmacología , Angiotensina I/farmacología , Presión Sanguínea/efectos de los fármacos , Circulación Pulmonar/efectos de los fármacos , Antagonistas de Receptores de Angiotensina , Animales , Captopril/farmacología , Gatos , Femenino , Imidazoles/farmacología , Masculino , Tetrazoles/farmacología
19.
Am J Physiol ; 266(6 Pt 2): H2256-67, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7517646

RESUMEN

Responses to bradykinin (BK) were investigated in the pulmonary vascular bed of the cat under conditions of controlled pulmonary blood flow and constant left atrial pressure when lobar arterial pressure was elevated to a high steady level. Under elevated-tone conditions, BK caused dose-related decreases in lobar arterial pressure. After administration of Hoe-140, a BK B2-receptor antagonist, vasodilator responses to BK were reduced in a selective manner. Vasodilator responses to BK were unchanged by atropine, glibenclamide, meclofenamate, or bronchial occlusion, suggesting that responses are not dependent on the activation of muscarinic receptors or K+ATP channels, the release of vasodilator prostaglandins, or changes in bronchomotor tone. The nitric oxide (NO) synthase inhibitors N omega-nitro-L-arginine benzyl ester and N omega-nitro-L-arginine reduced vasodilator responses to BK in a selective manner, indicating that responses to BK are mediated in part by the release of NO. Methylene blue, an inhibitor of the activation of soluble guanylate cyclase, increased lobar arterial pressure and decreased responses to BK. The increases in lobar arterial pressure in response to methylene blue were partially reversed by the administration of superoxide dismutase, indicating that generation of O2- may inactivate basally released NO. The duration of the response to BK was enhanced by the guanosine 3',5'-cyclic monophosphate (cGMP) phosphodiesterase inhibitor Zaprinast, suggesting that responses to BK involve increases in cGMP levels. Responses to BK were enhanced by captopril, indicating that BK is rapidly inactivated by kininase II in the lung.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Bradiquinina/farmacología , Circulación Pulmonar/efectos de los fármacos , 3',5'-GMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , Obstrucción de las Vías Aéreas/fisiopatología , Aminoácido Oxidorreductasas/antagonistas & inhibidores , Animales , Bradiquinina/análogos & derivados , Bradiquinina/antagonistas & inhibidores , Bronquios/fisiopatología , Gatos , Azul de Metileno/farmacología , Óxido Nítrico Sintasa , Purinonas/farmacología , Vasodilatación/fisiología
20.
Am J Physiol ; 266(6 Pt 2): H2416-22, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7517647

RESUMEN

The comparative effects of the nitric oxide (NO) synthase inhibitors N omega-nitro-L-arginine (L-NNA), N omega-nitro-L-arginine methyl ester (L-NAME), and N omega-nitro-L-arginine benzyl ester (L-NABE) on baseline tone and on vasodilator responses to acetylcholine (ACh), bradykinin (BK), and substance P (SP) were compared in the pulmonary vascular bed of the cat under constant flow conditions. After administration of the NO synthase inhibitors in intravenous doses of 100 mg/kg, the increase in lobar arterial pressure and the attenuation of vasodilator responses to ACh, BK, and SP were similar, whereas responses to adenosine and felodipine, endothelium-independent vasodilator agents, were not altered. In addition to inhibiting responses to ACh, BK, and substance P, the NO synthase inhibitors enhanced vasodilator responses to S-nitroso-N-acetylpenicillamine and NO. Moreover, atropine inhibited pulmonary vasodilator responses to ACh but not to SP or BK, and L-NAME or L-NABE had no effect on the decrease in heart rate in response to efferent vagal stimulation, a muscarinic receptor-mediated response that is independent of NO release. The similar inhibitory effects of L-NNA, L-NAME, and L-NABE on vasodilator responses to ACh, BK, and SP suggest that the L-arginine analogue, L-NNA, as well as the methyl and benzyl esters of L-NNA are useful probes for studying NO-mediated endothelium-dependent responses in the pulmonary vascular bed of the intact-chest cat.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Arginina/análogos & derivados , Circulación Pulmonar/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Vasodilatadores/farmacología , Acetilcolina/farmacología , Aminoácido Oxidorreductasas/antagonistas & inhibidores , Animales , Arginina/farmacología , Presión Sanguínea/efectos de los fármacos , Bradiquinina/farmacología , Gatos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Masculino , NG-Nitroarginina Metil Éster , Óxido Nítrico Sintasa , Nitroarginina , Sustancia P/farmacología
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