Regulation of (3h) arginine8 vasopressin binding to the rat renal medulla by guanine nucleotides

Lawrence E. Cornett, Daniel Dorsa

Research output: Contribution to journalArticle

6 Scopus citations

Abstract

In rat renal medullary membranes, we have examined modulatory effects of guanine nucleotides on binding of arginine vasopressin (AVP) to its receptor. Equilibrium binding studies analyzed by an iterative curve fitting program revealed an interaction of (3H) AVP with a single class of binding sites with a dissociation constant of 1.4±0.2 nM and a binding site concentration of 201±37 fmol/mg protein (n=6). With the addition of 100 μM guanylyl-imidodiphosphate (Gpp(NH)p), the binding site concentration was significantly (p <0.01) reduced to 151±36 fmol/mg protein with no change in receptor affinity. The nonhydrolyzable analogues, guanosine-53′O-(3-thiophosphate) and Gpp(NH)p were the most potent inhibitors of (3H) AVP binding. Guanosine 5′triphoshate and guanosine-5′diphosphate were both relatively poor inhibitors. Guanosine-5′monophosphate and adenosine 5′triphosphate did not inhibit (3H) AVP binding at concentrations up to 100 μM. Furthermore, 100 μM Gpp(NH)p accelerated the dissociation of (3H) AVP from the receptor. We conclude that guanine nucleotides are important modulators of AVP binding to the V2 receptor subtype in the renal medulla.

Original languageEnglish (US)
Pages (from-to)127-140
Number of pages14
JournalJournal of Receptors and Signal Transduction
Volume6
Issue number2
DOIs
Publication statusPublished - 1986
Externally publishedYes

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ASJC Scopus subject areas

  • Biochemistry
  • Cell Biology
  • Molecular Biology
  • Pharmacology

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