中枢和外周脑钠素(BNP)调节醛固酮分泌的不同作用

将BNP和AT-Ⅱ、ACTH AVP单独或BNP与这3种肽分别合并在大鼠icv或iv注入后观察血Ald浓度的变化。实验结果表明:①iv给予AVP(5μg/3ml·h~(-1))、ACTH(5μg/3ml·h~(-1))和AT-Ⅱ(5 v.g/3 ml·h(-1)),1h后均能增加血Ald的浓度。iv给予BNP(5μg/3ml·h(-1))能明显抑制AVP和ACTH的刺激作用,而不影响AT-Ⅱ的刺激作用。②icv给予BNP(2 Vg/10 pl NS)能降低血Aid浓度。icv给予AVP(2μg/10μl NS)能增加血Aid浓度,但ACTH(2μg/10μl NS)和AT-Ⅱ(2μg/10μl NS)无此种作用。但如脑室同时给予BNP(2μg/10μlNS)却可明显刺激Aid分泌。③icv注入BNP对外周注入的3种多肽的刺激作用无任何影响。从上述的实验结果可看出:脑内BNP可“反常”地增加AT-Ⅱ、ACTH和AVP对Ald分泌的刺激作用,与外周抑制AVP,ACTH的刺激作用不同。而脑内BNP不影响这3种多肽的外周刺激作用。结论是脑内BNP以其独特的方式调节Ald的分泌,控制水盐代谢。

Different Effect of Central and Peripheral Brain Natriuretic Peptide (BNP) on Aldosterone Secretion

It is sure that BNP plays a important role in regulation of aldosterone (Ald) secretion, but no one has reported that cerebral BNP (cBNP) and peripheral BNP (pBNP) have any difference in its regulation action.In order to solve this question, we have compared effects of cBNP administrated by icv and pBNP given by iv alone or associated with angiotensin II (AT-II), Adrenocorticotro-pin (ACTH) and Arginine Vasopressin (AVP) on regulation of Ald secretion.The results show that 1) AT-II, ACTHand AVP given by iv (5 μg/3ml· h^-1) could increase the concentration of plasma Aid.BNP (5μg/3ml· h^-1) inhibited the stimulation of ACTH and AVP, although BNP had not been discoved to have effect for AT-II; 2) BNP (2/μg in 10/μl NS)administrated by icy decreased the concentration of plas-ma Aid.icy injection of AVP (2 μg in 10 μl NS)could increase plasma Aid, but ACTH (2 μg in 10 μl NS) and AT-II (2 μg in 10 μl NS)did not have this effect.However, giving ACTH (2 μg in 10 μlNS) or AT-II(2 μg in 10 μl NS) individually with BNP (2 μg in 10 μl NS)could induce paradoxical stimulation on plasma Aid concentration, and 3) there were no effect on stimulation of Aid secretion induced by iv perfusion of AT-II, ACTH or AVP (5 μg/3ml· h^-1) when BNP (2 μg in 10 μl NS) was injected by icy.From above results, we found that there are certain differences between cBNP and pBNP on regulation of Aid secre-tion.Cerebral ACTH and AT-II can induce the increase of plasma Aid only in the condition of coo-peration with cBNP.