Burgess W J, Perrott M N, Balment R J
Department of Physiological Sciences, School of Biological Sciences, University of Manchester, UK.
J Mol Endocrinol. 1994 Apr;12(2):149-54. doi: 10.1677/jme.0.0120149.
It is unclear whether the diuretic effects of atrial natriuretic peptide (ANP) result, in part, from an inhibition of the renal actions of vasopressin. Moreover, accruing evidence suggests that the kidneys themselves may produce an ANP-like peptide, urodilatin, which shares many of the renal actions of ANP. The mechanism underlying the diuretic action of urodilatin has not yet been examined. Accordingly, we have investigated the potential modulatory actions of both ANP and urodilatin on vasopressin-stimulated cyclic AMP (cAMP) production in microdissected inner medullary collecting duct (IMCD) segments of rat kidney. ANP and urodilatin alone (at 10(-8) or 10(-6) M) had no demonstrable effect on cAMP accumulation in IMCD segments. Moreover, neither ANP nor urodilatin (each at 10(-6) M) significantly altered either the profile or the absolute magnitude of the cAMP response stimulated by vasopressin. These findings indicate that neither ANP nor urodilatin interacts with the vasopressin-sensitive adenylate cyclase site in the rat IMCD to contribute to its diuretic actions.
尚不清楚心房利钠肽（ANP）的利尿作用是否部分源于对血管加压素肾脏作用的抑制。此外，越来越多的证据表明，肾脏自身可能产生一种ANP样肽——尿钠素，它具有许多与ANP相同的肾脏作用。尿钠素利尿作用的潜在机制尚未得到研究。因此，我们研究了ANP和尿钠素对大鼠肾脏显微解剖的髓质内集合管（IMCD）节段中血管加压素刺激的环磷酸腺苷（cAMP）生成的潜在调节作用。单独使用ANP和尿钠素（浓度为10^(-8)或10^(-6) M）对IMCD节段中的cAMP积累没有明显影响。此外，ANP和尿钠素（均为10^(-6) M）均未显著改变血管加压素刺激刺激的cAMP反应的模式或绝对幅度。这些发现表明，ANP和尿钠素均不与大鼠IMCD中血管加压素敏感的腺苷酸环化酶位点相互作用以发挥其利尿作用。
