Effects of dietary salt on adrenomedullin and its receptor mrnas in rat kidney. Jensen, Boye L., Stepan Gambaryan, Elke Schmaus, and Armin Kurtz. Physiologisches Institut der Universit[umlaut]at Regensburg, D -93040 Regensburg, Germany and Medizinische Universit[umlaut]ats -Klinik, Klinische Biochemie and Pathobiochemie, W[umlaut]urzburg
APStracts 5:0053F, 1998.
There is accumulating evidence that adrenomedullin (ADM) is involved in the control of salt and water homeostasis. ADM is considered to act primarily in a paracrine fashion and since the kidneys are target organs for ADM we investigated the localization and regulation of ADM and ADM-receptor (ADM-R) mRNAs in the kidney. ADM- and ADM-R mRNAs were colocalized in renal vessels, glomeruli and in IMCD. ADM mRNA was also detected in proximal tubules, whereas ADM-R mRNA was found in distal convoluted tubules. By ribonuclease protection assay, the abundance of ADM mRNA was 4-fold higher in cortex than in outer medulla and papilla. In isolated glomeruli, ADM-mRNA was 3-fold higher compared to cortex. Conversely, ADM-R-mRNA was 4-fold higher in papilla than in renal cortex. This distribution of ADM- and ADM-R mRNA suggests a cortical source of ADM, and a preferential action of ADM in the papilla. Ten days of feeding a low salt (0.02 %) or a high salt diet (4 %) did not change ADM- or ADM-R mRNA in any kidney zone.

Received 1 October 1997; accepted in final form 17 February 1998.
APS Manuscript Number F316-7.
Article publication pending Am. J. Physiol. (Renal Physiology).
ISSN 1080-4757 Copyright 1998 The American Physiological Society.
Published in APStracts on 9 March 1998