AIM: To investigate the effects of verapamil on nitric oxide (NO) synthesis in a portal vein-ligated rat model. METHODS: Systemic and splanchnic hemodynamics were measured by radiolabeled microspheres in portal hy...AIM: To investigate the effects of verapamil on nitric oxide (NO) synthesis in a portal vein-ligated rat model. METHODS: Systemic and splanchnic hemodynamics were measured by radiolabeled microspheres in portal hypertensive rats after acute administration of verapamil (2 mg/kg) on chronic treatment with N^W-nitro-L-arginine (NNA)(80 mg/kg) and/or indomethacin (2 mg/kg) . RESULTS: Verapamil (2 mg/kg) caused a marked fall in both arterial pressure and cardiac output accompanied by an insignificant change in the portal pressure and no change in portal venous inflow. This result suggested that verapamil did not cause a reduction in portal vascular resistance of portal hypertensive rats, which was similar between N^w- nitro-Loarginine-treated and indomethacin-treated groups. CONCLUSION: In portal hypertensive rats pretreated with NNA and/or indomethacin, acute verapamil administration can not reduce the portal pressure, suggesting that NO and prostaglandin play an important role in the pathogenesis of splanchnic arterial vasodilation in portal hypertension.展开更多
Objective: To observe the therapeutic effect of electroacupuncture (EA) on plasma angiotensin (Ang Ⅱ), aldosterone (ALD) and atrial natriuretic polypeptide (ANP) contents in experimental cerebral infarction rabbits f...Objective: To observe the therapeutic effect of electroacupuncture (EA) on plasma angiotensin (Ang Ⅱ), aldosterone (ALD) and atrial natriuretic polypeptide (ANP) contents in experimental cerebral infarction rabbits for analyzing the underlying mechanism of acupuncture in ameliorating blood supply of the brain tissue. Methods: A total of 80 rabbits were randomized into control (n = 8), pseudo-operation (n = 24), model (n = 24) and EA (n = 24) groups. Cerebral infarction model was established by infusion of self-thrombus into the carotid artery. EA (1 mA, 2 Hz) was applied to 'Baihui'(百会 GV 20) and 'Shuigou'(水沟 GV 26) for 30 min, once every 12 hours. Plasma Ang Ⅱ, ALD and ANP contents were detected with radioimmunoassay method. In the later 3 groups, blood samples were taken at 6 h, 24 h and 48 h after cerebral ischemia. Results: Compared with control and pseudo-operation groups, Ang Ⅱ and ALD contents of model group at 6 h, 24 h and 48 h after cerebral ischemia increased significantly while plasma ANP of the 3 time-courses of model group decreased considerably (P<0.01). In comparison with model group, results showed that Ang-Ⅱ and ALD contents of EA group decreased significantly whereas ANP level of EA group increased strikingly (P<0.01). Conclusion: Electroacupuncture has the effects of raising plasma ANP level and lowering plasma Ang-Ⅱ and ALD in cerebral infarction rabbits.展开更多
基金Supported by the grant from China Medical University Hospital, Taichung, Taiwan, China
文摘AIM: To investigate the effects of verapamil on nitric oxide (NO) synthesis in a portal vein-ligated rat model. METHODS: Systemic and splanchnic hemodynamics were measured by radiolabeled microspheres in portal hypertensive rats after acute administration of verapamil (2 mg/kg) on chronic treatment with N^W-nitro-L-arginine (NNA)(80 mg/kg) and/or indomethacin (2 mg/kg) . RESULTS: Verapamil (2 mg/kg) caused a marked fall in both arterial pressure and cardiac output accompanied by an insignificant change in the portal pressure and no change in portal venous inflow. This result suggested that verapamil did not cause a reduction in portal vascular resistance of portal hypertensive rats, which was similar between N^w- nitro-Loarginine-treated and indomethacin-treated groups. CONCLUSION: In portal hypertensive rats pretreated with NNA and/or indomethacin, acute verapamil administration can not reduce the portal pressure, suggesting that NO and prostaglandin play an important role in the pathogenesis of splanchnic arterial vasodilation in portal hypertension.
文摘Objective: To observe the therapeutic effect of electroacupuncture (EA) on plasma angiotensin (Ang Ⅱ), aldosterone (ALD) and atrial natriuretic polypeptide (ANP) contents in experimental cerebral infarction rabbits for analyzing the underlying mechanism of acupuncture in ameliorating blood supply of the brain tissue. Methods: A total of 80 rabbits were randomized into control (n = 8), pseudo-operation (n = 24), model (n = 24) and EA (n = 24) groups. Cerebral infarction model was established by infusion of self-thrombus into the carotid artery. EA (1 mA, 2 Hz) was applied to 'Baihui'(百会 GV 20) and 'Shuigou'(水沟 GV 26) for 30 min, once every 12 hours. Plasma Ang Ⅱ, ALD and ANP contents were detected with radioimmunoassay method. In the later 3 groups, blood samples were taken at 6 h, 24 h and 48 h after cerebral ischemia. Results: Compared with control and pseudo-operation groups, Ang Ⅱ and ALD contents of model group at 6 h, 24 h and 48 h after cerebral ischemia increased significantly while plasma ANP of the 3 time-courses of model group decreased considerably (P<0.01). In comparison with model group, results showed that Ang-Ⅱ and ALD contents of EA group decreased significantly whereas ANP level of EA group increased strikingly (P<0.01). Conclusion: Electroacupuncture has the effects of raising plasma ANP level and lowering plasma Ang-Ⅱ and ALD in cerebral infarction rabbits.