Conclusion: The changes of circadian variation of blood pressure are associated with the role of sympathetic nerve and intracardial renin angiotensin system.

结论血压昼夜变化受交感神经与肾血管紧系统作用有关。

Renin, a proteolytic enzyme formed in the granules of the juxtaglomerular apparatus cells, catalyzes conversion of the protein angiotensinogen to angiotensin I, a decapeptide.

肾是肾小球旁体细胞颗粒内形成的一种蛋白水解酶，催化蛋白血管紧原转换为血管紧Ⅰ，即十肽。