Suzuki H, Shibata H, Murakami M, Sato A, Naito M, Ichihara A, Matsumoto A, Tsujimoto G, Hirasawa A, Horie K
Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan.
Endocr J. 1995 Feb;42(1):15-22. doi: 10.1507/endocrj.42.15.
The objective of the present study was to quantify the expression of angiotensin II type 1 (AT1) receptor transcripts in human blood cells--platelets and mononuclear leukocytes--from 10 normal healthy volunteers during the alterations in the renin-angiotensin system. A quantitative assay employing reverse transcription-polymerase chain reaction (RT-PCR) was utilized. Oral administration of furosemide, 40 mg for 2 days, under mild salt restriction (50 mEq NaCl/day) for 6 days stimulated the renin-angiotensin system resulting in significant increases in plasma renin activity (PRA) (1.84 +/- 0.12 vs. 1.05 +/- 0.17 ng/l/s; P < 0.01), plasma angiotensin II concentration, and plasma aldosterone concentration (PAC). The ratio of AT1 receptor mRNA to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA expression in mononuclear leucocytes was significantly (P < 0.05) increased from the basal level (0.49 +/- 0.05 vs. 0.29 +/- 0.03) (P < 0.01), while in platelets these changes were opposite (0.11 +/- 0.05 vs. 0.25 +/- 0.05) (P < 0.01). Compared to these significant changes, salt loading (200 mEq NaCl/day) for 6 days decreased PRA(0.49 +/- 0.10 vs. 1.05 +/- 0.17 ng/l/s; P < 0.01) and induced the opposite changes in the ratio of AT1 receptor/GAPDH mRNA. These data suggest that AT1 receptors in human blood cells may be of two different types--platelets and mononuclear leucocytes.
本研究的目的是在肾素 - 血管紧张素系统发生改变期间，对10名正常健康志愿者的人血细胞（血小板和单核白细胞）中血管紧张素II 1型（AT1）受体转录本的表达进行定量。采用了逆转录 - 聚合酶链反应（RT-PCR）定量分析方法。在轻度限盐（50 mEq氯化钠/天）6天的情况下，口服速尿40 mg，持续2天，刺激肾素 - 血管紧张素系统，导致血浆肾素活性（PRA）显著升高（1.84±0.12对1.05±0.17 ng/l/s；P<0.01）、血浆血管紧张素II浓度和血浆醛固酮浓度（PAC）升高。单核白细胞中AT1受体mRNA与甘油醛 - 3 - 磷酸脱氢酶（GAPDH）mRNA表达的比值从基础水平显著升高（P<0.05）（0.49±0.05对0.29±0.03）（P<0.01），而血小板中的这些变化则相反（0.11±0.05对0.25±0.05）（P<0.01）。与这些显著变化相比，6天的高盐负荷（200 mEq氯化钠/天）降低了PRA（0.49±0.10对1.05±0.17 ng/l/s；P<0.01），并诱导了AT1受体/GAPDH mRNA比值的相反变化。这些数据表明，人血细胞中的AT1受体可能有两种不同类型——血小板和单核白细胞。
