RESUMEN
AIM: To explore the effects of experimental subarachnoid hemorrhage (SAH) on rabbit urinary bladder and to assess the potential protective effects of hyperbaric oxygen therapy (HBOT). METHODS: A total of 15 male New Zealand white rabbits were divided randomly to one of three groups: group I was spared as the control group (n = 5), group II was exposed to SAH, received no treatment, and acted as the SAH group (n = 5) and group III was exposed to SAH and received five sessions of HBOT (started 12 hours after SAH induction and was given twice daily for the first 2 days and once on the third day) and acted as the treatment group (n = 5). At 72 hours after the SAH induction, bladders from all animals were removed for in vitro organ bath experiments and biochemical analyses. RESULTS: Isometric tension studies revealed that compared to group I, the contractile responses of the strips to carbachol in group II were significantly decreased whereas HBOT restored the contractile responses (P < .05). Caspase-3 and nitric oxide synthase (NOS) activities of bladder tissues were significantly increased in group II when compared with group I, whereas caspase-3 and NOS activities were significantly decreased in the tissues of group III (P < .01). CONCLUSIONS: Subarachnoid hemorrhage stimulates apoptosis of the rabbit bladder and impairs the contractile response of the rabbit bladder to carbachol. HBOT creates a protective effect in rabbit bladder tissues and restores SAH-induced changes.
Asunto(s)
Apoptosis/fisiología , Oxigenoterapia Hiperbárica , Contracción Muscular/fisiología , Hemorragia Subaracnoidea/terapia , Vejiga Urinaria/fisiopatología , Animales , Apoptosis/efectos de los fármacos , Carbacol/farmacología , Caspasa 3/metabolismo , Modelos Animales de Enfermedad , Masculino , Contracción Muscular/efectos de los fármacos , Óxido Nítrico Sintasa/metabolismo , Conejos , Hemorragia Subaracnoidea/metabolismo , Hemorragia Subaracnoidea/fisiopatología , Vejiga Urinaria/efectos de los fármacos , Vejiga Urinaria/metabolismoRESUMEN
OBJECTIVES: To examine the possible protective effect of quercetin (QT), which is well known for its antioxidant and protective effects in circumstances of oxidative stress, on urinary bladder tissue in a rat model of ischemia/reperfusion (I/R) injury, which is a known factor for the development of lower urinary tract dysfunction partly mediated by the generation of free radicals causing oxidative damage. METHODS: Thirty male Sprague-Dawley rats were subjected to I/R injury through clamping the abdominal aorta for 30 min and then allowing reperfusion for the next 60 min. Quercetin (20 mg/kg; subcutaneously) or vehicle were given before ischemia and just before reperfusion. Findings of the isometric contraction studies in the organ bath and of the histological examinations along with oxidative stress markers were evaluated in bladder tissues. RESULTS: Increased malondialdehyde (MDA) levels and myeloperoxidase (MPO) activities and decreased glutathione (GSH) levels and superoxide dismutase (SOD) activities in the I/R group were reduced by QT treatment. In the I/R group, pro-apoptotic marker caspase-3 was increased and anti-apoptotic bcl-2 protein was decreased, while QT treatment significantly reversed these parameters. In the I/R group contractile responses of the bladder strips to carbachol were significantly lower than those of the control group, which were reversed by QT treatment. CONCLUSION: Quercetin treatment protects bladder tissue contractility against acute I/R injury by decreasing oxidative stress and apoptosis induced by I/R.
Asunto(s)
Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Quercetina/farmacología , Daño por Reperfusión/prevención & control , Vejiga Urinaria/efectos de los fármacos , Animales , Caspasas/metabolismo , Glutatión/metabolismo , Contracción Isométrica/efectos de los fármacos , Masculino , Malondialdehído/metabolismo , Contracción Muscular/efectos de los fármacos , Peroxidasa/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas Sprague-Dawley , Superóxido Dismutasa/metabolismoRESUMEN
It has been previously shown that acetylcholine (ACh) may affect pro-inflammatory and anti-inflammatory cytokines. The role of the cholinergic system in radiation-induced inflammatory responses and tissue damage remains unclear. Therefore, the present study was designed to determine the radio-protective properties of the cholinergic system in the ileum and the liver of rats. Rats were exposed to 8-Gy single-fraction whole-abdominal irradiation and were then decapitated at either 36 h or 10 d post-irradiation. The rats were treated either with intraperitoneal physiological saline (1 ml/kg), physostigmine (80 µg/kg) or atropine (50 µg/kg) twice daily for 36 h or 10 d. Cardiac blood samples and liver and ileal tissues were obtained in which TNF-α, IL-1ß and IL-10 levels were assayed using ELISA. In the liver and ileal homogenates, caspase-3 immunoblots were performed and myeloperoxidase (MPO) activity was analyzed. Plasma levels of IL-1ß and TNF-α increased significantly following radiation (P < 0.01 and P < 0.001, respectively) as compared with non-irradiated controls, and physostigmine treatment prevented the increase in the pro-inflammatory cytokines (P < 0.01 and P < 0.001, respectively). Plasma IL-10 levels were not found to be significantly changed following radiation, whereas physostigmine augmented IL-10 levels during the late phase (P < 0.01). In the liver and ileum homogenates, IL-1ß and TNF-α levels were also elevated following radiation, and this effect was inhibited by physostigmine treatment but not by atropine. Similarly, physostigmine also reversed the changes in MPO activity and in the caspase-3 levels in the liver and ileum. Histological examination revealed related changes. Physostigmine experiments suggested that ACh has a radio-protective effect not involving the muscarinic receptors.
Asunto(s)
Acetilcolina/inmunología , Enfermedades del Íleon/inmunología , Enfermedades del Íleon/prevención & control , Hepatopatías/inmunología , Hepatopatías/prevención & control , Traumatismos por Radiación/inmunología , Traumatismos por Radiación/prevención & control , Animales , Colinérgicos/administración & dosificación , Citocinas/inmunología , Enfermedades del Íleon/patología , Hepatopatías/patología , Dosis de Radiación , Traumatismos por Radiación/patología , Ratas , Ratas Sprague-Dawley , Resultado del TratamientoRESUMEN
Oxidative stress plays an important role both in spinal cord injury (SCI) and erectile dysfunction (ED). The present study investigated the effects of melatonin and tadalafil treatment alone or in combination on SCI-induced ED. Male Wistar albino rats (n = 40) were divided into five groups: sham-operated control and SCI-injured rats given either vehicle, melatonin (10 mg/kg, i.p.), tadalafil (10 mg/kg, p.o.) or a combination of melatonin and tadalafil. Spinal cord injury was induced using a standard weight-drop method. On Day 7 after SCI, intracavernosal pressure (ICP) was measured and all rats were decapitated. Cavernosal tissues were obtained to examine caspase 3, nitric oxide synthase (NOS), myeloperoxidase (MPO) and superoxide dismutase (SOD) activities, as well as cGMP, nerve growth factor (NGF), malondialdehyde (MDA) and glutathione (GSH) levels. Spinal cord injury caused oxidative damage, as evidenced by increases in MDA and cGMP levels. In addition, MPO and caspase 3 activites were increased after SCI, whereas GSH and NGF levels and SOD activity were reduced. Melatonin effectively reversed these oxidative changes. Furthermore, in rats treated with both melatonin and tadalafil, the recoveries were more pronounced than in rats given either melatonin or tadalafil alone. The ICP/mean arterial pressure value in vehicle-treated SCI rats was significantly higher than in the control group, whereas in the tadalafil- and tadalafil + melatonin-treated groups have returned this value had returned to control levels. As an individual treatment, and especially when combined with tadalafil, a well-known agent in the treatment of ED, melatonin prevented SCI-induced oxidative damage to cavernosal tissues and restored ED, most likely due to its anti-oxidant effects.