慢性高盐摄入对大鼠心房利钠肽肾脏清除受体的选择性下调作用：使用125I标记的C型心房利钠肽-（4-23）对分离膜进行的研究

Selective downregulation of rat renal clearance receptors for atrial natriuretic peptide by chronic high-salt intake: study on isolated membranes using 125I-labelled c-atrial natriuretic peptide-(4-23).

Michel H, Bäcker A, Kramer H J

Medical Policlinic, University of Bonn, Federal Republic of Germany.

Clin Sci (Lond). 1992 Aug;83(2):139-42. doi: 10.1042/cs0830139.

Abstract

125I-labelled c-atrial natriuretic peptide-(4-23) was used as radioligand for the direct quantification of atrial natriuretic peptide clearance receptors, and 125I-labelled rat atrial natriuretic peptide-(1-28) was used for the determination of total and biologically active atrial natriuretic peptide receptors, in renal glomerular and papillary membrane preparations of chronically salt-loaded and control rats. 2. The membrane preparation technique included acid-washing (pH 5), and receptor binding was assessed by saturation studies at 4 degrees C for 3 h. Chronic salt loading revealed a 35% decrease in clearance receptor number in the glomerular membrane and a 42% decrease in the papillary membranes. The absolute decrease in clearance receptor number was almost identical with the observed reduction in absolute number of total atrial natriuretic peptide receptors. Biologically active receptors were not affected by chronic salt loading. 3. Selective downregulation of clearance receptors for atrial natriuretic peptide may reflect an important role for the rat renal atrial natriuretic peptide system in long-term fluid and electrolyte regulation.

摘要

用¹²⁵I标记的C型心房利钠肽（4 - 23）作为放射性配体，用于直接定量心房利钠肽清除受体；用¹²⁵I标记的大鼠心房利钠肽（1 - 28）用于测定慢性盐负荷大鼠和对照大鼠肾肾小球及乳头膜制剂中总的和生物活性的心房利钠肽受体。2. 膜制备技术包括酸洗（pH 5），受体结合通过在4℃下进行3小时的饱和研究来评估。慢性盐负荷使肾小球膜中清除受体数量减少35%，乳头膜中减少42%。清除受体数量的绝对减少与观察到的总心房利钠肽受体绝对数量的减少几乎相同。生物活性受体不受慢性盐负荷的影响。3. 心房利钠肽清除受体的选择性下调可能反映了大鼠肾心房利钠肽系统在长期液体和电解质调节中的重要作用。