探讨ｃＧＭＰ是否介导Ｌ精氨酸（一氧化氮合酶底物）引起的血管加压素（ＡＶＰ）释放增多效应．方法：用放射免疫法测定大鼠血浆中ＡＶＰ水平．结果：侧脑室分别注射Ｌ精氨酸和８溴ｃＧＭＰ（一种可透过膜的ｃＧＭＰ衍生物）能刺激血浆ＡＶＰ水平增加［分别从（３２±０５）升至（５８±１４）ｎｇ·Ｌ－１，从（２６±０３）升至（６６±０４）ｎｇ·Ｌ－１，Ｐ＜００１］，同时注射Ｌ精氨酸和亚甲蓝（鸟苷酸环化酶抑制剂）对血浆ＡＶＰ的水平没有影响．结论：ｃＧＭＰ介导Ｌ精氨酸引起的ＡＶＰ释放增加效应 To investigate whether cGMP mediates the increase of vasopressin (AVP) release induced by L-arginine (nitric oxide synthase substrate). Methods: The level of AVP in plasma of rats was determined by radioimmunoassay. RESULTS: Intracerebroventricular injection of L-arginine and 8-bromo-cGMP, a transmembrane-permeable cGMP derivative, stimulated an increase in plasma AVP levels (from 3.2 ± 0.5) to 58 ± 14) ng · L-1, from (26 ± 03) to (66 ± 04) ng · L-1, P <001] L-arginine and methylene blue (guanylate cyclase inhibitors) have no effect on plasma AVP levels. Conclusion: cGMP mediates L-arginine-induced increase of AVP release