Korean J Physiol Pharmacol.  2000 Aug;4(4):311-318.

Asymmetrical distribution of P2Y nucleotide receptors in rabbit inner medullary collecting duct cells

• Woo JS
• Jung JS
• Kim YK

Abstract

We cultured the rabbit inner medullary collecting duct (IMCD) cells as monolayers on collagen-coated membrane filters, and investigated distribution of the P2Y receptors by analyzing nucleotide-induced short circuit current (Isc) responses. Exposure to different nucleotides of either the apical or basolateral surface of cell monolayers stimulated Isc. Dose-response relationship and cross-desensitization studies suggested that at least 3 distinct P2Y receptors are expressed asymmetrically on the apical and basolateral membranes. A P2Y2-like receptor, which responds to UTP and ATP, is expressed on both the apical and basolateral membranes. In addition, a uracil nucleotide receptor, which responds to UDP and UTP, but not ATP, is expressed predominantly on the apical membrane. In contrast, a P2Y1-like receptor, which responds to ADP and 2-methylthio-ATP, is expressed predominantly on the basolateral membrane. These nucleotides stimulated intracellular cAMP production with an asymmetrical profile, which was comparable to that in the stimulation of Isc. Our results suggest that the adenine and uracil nucleotides can interact with different P2Y nucleotide receptors that are expressed asymmetrically on the apical and basolateral membranes of the rabbit IMCD cells, and that both cAMP- and Ca2+-dependent signaling mechanisms underlie the stimulation of Isc.

Keyword

IMCD cells; Nucleotide; P2Y receptor; Chloride secretion; Short circuit current

MeSH Terms

Adenine
Adenosine Diphosphate
Adenosine Triphosphate
Membranes
Nucleotides
Uracil
Uracil Nucleotides
Uridine Diphosphate
Uridine Triphosphate
Adenine
Adenosine Diphosphate
Adenosine Triphosphate
Nucleotides
Uracil
Uracil Nucleotides
Uridine Diphosphate
Uridine Triphosphate