Churchill P C
Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan 48201.
Clin Exp Hypertens A. 1988;10(6):1189-202. doi: 10.1080/07300077.1988.11878910.
The renin-angiotensin system plays a central role in salt and water balance and in the regulation of arterial blood pressure. The level of activity of this system is determined primarily by the rate at which the granulated juxtaglomerular cells (JG cells) secrete renin into the blood. Physiologically, renin secretory rate is controlled by a number of first messengers: afferent arteriolar transmural pressure or some function of it, such as stretch (the baroreceptor mechanism); solute transport in the macula densa segment of the nephron (the macula densa mechanism); catecholamines released from the renal nerves and the adrenal medulla (the beta-adrenergic mechanism); extracellular concentrations of many organic and inorganic substances including angiotensin II, vasopressin, K, and Mg (1-3). In addition to these physiological first messengers, a number of pharmacological agents affect renin secretion (3). It is an accepted principle of cellular biology that first messengers act by affecting the intracellular concentrations of only a few second messengers. The evidence that intracellular free ionic calcium, cyclic AMP, and cyclic GMP are second messengers in renin secretion has been reviewed in detail recently (4-9). These reviews are cited extensively, since space limitations precluded citing all the original literature.
肾素-血管紧张素系统在盐和水平衡以及动脉血压调节中起核心作用。该系统的活性水平主要由颗粒状球旁细胞（JG细胞）向血液中分泌肾素的速率决定。在生理情况下，肾素分泌速率受多种第一信使控制：入球小动脉跨壁压力或其某些功能，如牵张（压力感受器机制）；肾单位致密斑段的溶质转运（致密斑机制）；肾神经和肾上腺髓质释放的儿茶酚胺（β-肾上腺素能机制）；包括血管紧张素II、血管升压素、钾和镁在内的许多有机和无机物质的细胞外浓度（1-3）。除了这些生理性第一信使外，一些药理剂也会影响肾素分泌（3）。细胞生物学的一个公认原则是，第一信使通过仅影响少数第二信使的细胞内浓度来发挥作用。细胞内游离离子钙、环磷酸腺苷和环磷酸鸟苷作为肾素分泌第二信使的证据最近已得到详细综述（4-9）。由于篇幅限制无法引用所有原始文献，因此这些综述被广泛引用。
