Quantitative changes in rat renin secretory granules after acute and chronic stimulation of the renin system
Quantitative changes in rat renin secretory granules after acute and chronic stimulation of the renin system
复制标题
肾素系统急慢性刺激后大鼠肾素分泌颗粒的数量变化
DOI：
10.1007/s004410051085
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发表时间：
1998
影响因子：
3.6
通讯作者：
O. Skøtt
中科院分区：
文献类型：
--
作者：
R. Rasch;B. Jensen;J. Nyengaard;O. Skøtt
摘要 为研究肾素分泌的细胞模式，用体视学方法测量了刺激肾素系统时大鼠肾素分泌颗粒的数量和体积。当肾灌流压力降低至40毫米汞柱5分钟时，血浆肾素浓度(PRC)增加一倍，但对每个小动脉的肾素颗粒数或含肾素的小动脉体积无显著影响。慢性刺激是通过低盐饮食和抑制血管紧张素转换酶(ACE)14天的组合实现的，并导致PRC增加36倍，每个小动脉的颗粒数量增加20倍，含有肾素的小动脉体积增加17倍。慢性刺激大鼠肾灌流压力降低至40毫米汞柱5分钟后，Pcr进一步增加(1.6倍)，每小动脉颗粒数显著减少4000个(减少45%)，但对含肾素的小动脉体积无明显影响。肾素颗粒平均大小为0.35μm~3，组间无显着性差异。我们的结论是，招募的颗粒细胞对肾素的释放有显著贡献，小动脉沿线的所有颗粒细胞都参与了分泌反应。急性刺激后肾素颗粒数量的减少与胞吐作用是肾素释放的主要机制相一致。
Abstract In order to study the cellular mode of renin secretion, stereological methods were used to estimate number and volume of rat renin secretory granules during stimulation of the renin system. An acute decrease in renal perfusion pressure to 40 mmHg for 5 min increased plasma renin concentration (PRC) twofold, but did not significantly change the number of renin granules per arteriole or the renin-containing volume of the arteriole. Chronic stimulation was achieved by a combination of low-salt diet and inhibition of angiotensin-converting enzyme (ACE) for 14 days, and resulted in a 36-fold increase in PRC, a 20-fold increase in the number of granules per arteriole, and a 17-fold increase in the arteriolar volume that contained renin. An acute decrease in renal perfusion pressure to 40 mmHg for 5 min in the chronically stimulated rats increased PRC further (1.6-fold), and significantly reduced the number of granules per arteriole by 4000 (45% reduction), but did not change the renin-containing arteriolar volume significantly. The average renin granule size was 0.35 μm3 with no significant differences among the groups. We conclude that recruited granular cells contribute significantly to renin release, and that all granular cells along the arteriole participate in secretory responses. The reduced number of renin granules after acute stimulation is compatible with exocytosis as the dominating mechanism of renin release.