Jennings D B, Flynn T G
Department of Physiology, Queen's University, Kingston, Ont., Canada.
Can J Physiol Pharmacol. 1989 Oct;67(10):1372-9. doi: 10.1139/y89-220.
Administration of a newly discovered second atrial peptide, iso-atrial natriuretic peptide (or iso-rANP(1-45) for the rat), caused hypotension, decreased heart rate, diuresis, and increased renal excretion of Na+, K+, and Cl- in the anesthetized rat. Bolus injections of chemically synthetic iso-rANP(1-45) had circulatory and diuretic activity equal to or greater than rANP(99-126) but, at low doses, a lesser effect on renal electrolyte excretion. The synthetic peptide fragment, iso-rANP(17-45), analogous in structure to rANP(99-126), had attenuated activity on the circulation, and at low doses, attenuated activity on the kidney. At higher doses, where renal responses to rANP(99-126) were less (downside of a biphasic response), both iso-rANP(1-45) and (17-45) had greater effects on water and electrolyte excretion than rANP(99-126). Injections of iso-rANP(1-45) and (17-45) increased hematocrit, whereas rANP(99-126) did not; furthermore, unlike rANP(99-126), iso-rANP did not affect arterial plasma Na+ concentration. The heart produces at least two genetically different atrial natriuretic peptides which affect the circulation and salt and water balance.
给予一种新发现的第二种心房肽，即异心房利钠肽（或大鼠的异rANP(1 - 45)），可导致麻醉大鼠出现低血压、心率降低、利尿，并增加肾脏对Na+、K+和Cl-的排泄。静脉推注化学合成的异rANP(1 - 45)具有与rANP(99 - 126)相当或更强的循环和利尿活性，但在低剂量时，对肾脏电解质排泄的影响较小。合成肽片段异rANP(17 - 45)，其结构与rANP(99 - 126)类似，对循环系统的活性减弱，在低剂量时，对肾脏的活性也减弱。在较高剂量时，rANP(99 - 126)的肾脏反应较小（双相反应的不利方面），异rANP(1 - 45)和(17 - 45)对水和电解质排泄的影响均大于rANP(99 - 126)。注射异rANP(1 - 45)和(17 - 45)会使血细胞比容升高，而rANP(99 - 126)则不会；此外，与rANP(99 - 126)不同，异rANP不影响动脉血浆Na+浓度。心脏至少产生两种基因不同的心房利钠肽，它们影响循环以及盐和水平衡。
