APStracts 2:0006F, 1995.

Luminal prostaglandin e2 modulates sodium and water transport in the rabbit cortical collecting duct.. Ando, Yasuhiro, and Yasushi Asano. Division of Nephrology, Jichi Medical School, Yakushiji 3311-1, Minamikawachi, Kawachi, Tochigi, JAPAN 329-04

APStracts 2:0006F, 1995.

We have previously found that vasopressin acts not only from the basolateral side but also from the luminal side of the rabbit cortical collecting duct (CCD). In the present study, we examined if prostaglandin E2 (PGE2), another classic and potent modulator of the collecting duct functions, exerts luminal actions in the rabbit CCD perfused in vitro. While luminal prostaglandin I2 was inert, luminal PGE2 (>1nM) induced transient hyperpolarization of Vt followed by sustained depolarization in a dose-dependent manner. This action was preserved in the presence of basolateral PGE2, luminal AVP or luminal BaCl2, but abolished by basolateral ouabain or luminal amiloride. Further, unlike luminal AVP, luminal PGE2 suppressed sodium transport and increased osmotic water permeability. The present study suggests that PGE2, like AVP but in different fashions, modulates transepithelial transports from amphilateral sides in the CCD in vivo.

Received 15 February 1994; accepted in final form 3 January 1995.
APS Manuscript Number F51-4.
Article publication pending Am. J. Physiol. (Renal Fluid Electrolyte
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 23 February 1995.