ADMA在交感神经损毁自发性高血压大鼠中的作用

摘要

Objective To explore the role of asymmetric dimethylarginine(ADMA) in sympathectomized spontaneously hypertensive rat(SHR). Methods SHR pups were pharmacologically sympathectomized to investigate the role of sympathetic activity on ADMA. Systolic and diastolic blood pressure was monitored by tail-cuff method. Urine norepinephrine(NE) excretion of 6 hours collected using metabolic cages was detected. The levels of L-Arginine, ADMA, symmetric dimethylarginine and NE were evaluated in kidneys, heart and aorta in SHR by HPLC. No content and NOS activity in SHR kidney were determined by colorimetry. Results Neonatal chemical sympathectomy elicited a marked reduction of urinary NE excretion and NE contents in kidneys, heart and aorta and in the sympathectomized SHR compared with the sympathetically-intact SHR (P＜0. 01). Sympathectomy resulted in a reduction of systolic blood pressure and diastolic blood pressure in 12 week old SHR compared with the sympathetically-intact SHR (P＜0. 01). The sympathectomized SHR had a significant lower renal ADMA content than the sympathetically-intact SHR, moreover, the levels of NO content and NOS activity increased (P＜0.05). Conclusion Sympathetic nerve system may regulate blood pressure by ADMA.%目的 探讨不对称二甲基精氨酸(ADMA)在交感神经损毁自发性高血压大鼠(SHR)中的作用.方法 利用化学交感神经切断术损毁SHR交感神经,分成交感神经损毁组和对照组,测量常温下鼠尾血压.采用代谢笼法收集大鼠 6 h尿液,检测尿液去甲肾上腺素(NE)排泄量.HPLC法检测SHR大鼠心脏、肾脏及主动脉NE、血管中精氨酸、ADMA及对称二甲基精氨酸含量.比色法检测大鼠NO含量和 NOS活性.结果 与对照组相比,交感神经损毁组尿NE排泄量及肾脏、心脏及主动脉NE含量均明显降低(P<0. 01).交感神经损毁组血压明显低于对照组(P<0.01).与对照组相比,交感神经损毁组肾脏ADMA明显降低,NO含量及 NOS明显升高(P<0.05).结论 交感神经系统可能通过调控ADMA影响血压.