Submitted September 10, 2007
Returned for revision October 4, 2007
Accepted February 26, 2008
Female Reproductive Tract
Effect of Basolateral Adenosine Triphosphate on Chloride Secretion by Bovine Oviductal Epithelium
N. Keating
and
L. R. Quinlan *
* To whom correspondence should be addressed. E-mail: leo.quinlan{at}nuigalway.ie.
Abstract
The composition of the fluid within the oviduct is largely determined by the secretory and absorptive activities of the oviduct epithelium. The present study explored the effects of basolateral nucleotide stimulation on ion transport in the bovine oviduct using the Using chamber short-circuit current technique. Basolateral application of ATP induced a rapid transient increase in ion secretion by oviduct epithelial monolayers in a concentration-dependent manner. The ATP-induced ISC response was preserved in the presence of amiloride, while it was reduced in the absence of extracellular chloride or in the presence of bumetanide. The channels underlying the chloride secretory response were identified as Ca2+-activated Cl- channels and CFTR. The ATP-induced Cl- secretory response was largely preserved in the absence of extracellular Ca2+ but was significantly reduced in the presence of BAPTA-AM, thapsigargin or APB, demonstrating an important role for intracellular Ca2+ signaling in mediating these effects. A nucleotide potency profile of ATP=UTP>ADP, sensitivity to suramin and cross-desensitization by basolateral UTP, suggests that ATP exerted its effects on chloride secretion through the purinergic receptor P2Y, G-protein coupled 2, the presence of the P2RY2 gene was confirmed by reverse-trancriptase PCR. These results provide strong evidence that purinergic signaling constitutes a key mechanism of regulating chloride secretion and thus fluid formation in the bovine oviduct.
Key words:
Female Reproductive Tract •
Oviduct •
Signal transducers •
Signal transduction
