JPET

Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Schiemann, W. P.
Right arrow Articles by Buxton, I. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Schiemann, W. P.
Right arrow Articles by Buxton, I. L.

Action of adenosine in estrogen-primed nonpregnant guinea pig myometrium: characterization of the smooth muscle receptor and coupling to phosphoinositide metabolism

WP Schiemann, KO Doggwiler and IL Buxton

Department of Pharmacology, University of Nevada School of Medicine, Reno.

The smooth muscle of guinea pig uterus is contracted by adenosine in a manner consistent with the presence of a purine nucleoside receptor of the P1-A1 subtype that is uncoupled from adenylate cyclase. Here we investigate the signal transduction mechanism responsible for adenosine's ability to contract uterine smooth muscle. The A1 adenosine receptor antagonist [3H]-8-cyclopentyl-1.3- dipropyl xanthine ([3H]CPX) bound reversibly to a large number (172 +/- 25 fmol/mg of protein) of receptors in myometrial smooth muscle membranes from estrogen-primed virgin guinea pigs with an affinity (KD = 1.77 +/- 0.21 nM) similar to that expected of [3H]CPX binding to both central and peripheral A1 receptors. In the absence of the stable GTP analog, guanosine-5'-O-[3- thiotriphosphate], agonist competition of [3H]CPX binding resulted in a biphasic curve that was best fit assuming the presence of equal populations of two affinity states of the receptor. Addition of guanosine-5'-O-[3-thiotriphosphate] (10 microM) resulted in a monophasic competition curve of low affinity suggesting coupling of this A1 receptor to effector via a GTP binding protein. In [3H]myo- inositol labeled strips of myometrial smooth muscle, the adenosine agonist R-phenylisopropyl adenosine (R-PIA) stimulated the rapid formation of inositol-1,4,5-trisphosphate (InsP3) that was antagonized by addition of the nucleoside receptor antagonist 8-sulfophenyl theophylline. Prostaglandin stimulation of myometrial strips also increased InsP3 formation. Furthermore, R-PIA stimulated the disappearance of inositol phosphate (InsP) in a fashion consistent with agonist stimulation of an inositol phosphatase activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Volume 258, Issue 2, pp. 429-437, 08/01/1991
Copyright © 1991 by American Society for Pharmacology and Experimental Therapeutics




This article has been cited by other articles:


Home page
 ReproductionHome page
K. Yasuda, T. Nakamoto, M. Yasuhara, H. Okada, T. Nakajima, H. Kanzaki, M. Hori, and H. Ozaki
Role of protein kinase C{beta} in rhythmic contractions of human pregnant myometrium
Reproduction, April 1, 2007; 133(4): 797 - 806.
[Abstract] [Full Text] [PDF]

Home page
 Pharmacol. Rev.Home page
V. Ralevic and G. Burnstock
Receptors for Purines and Pyrimidines
Pharmacol. Rev., September 1, 1998; 50(3): 413 - 492.
[Abstract] [Full Text] [PDF]


Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
All ASPET Journals Molecular Pharmacology Pharmacological Reviews
Molecular Interventions Drug Metabolism and Disposition

Copyright © 1991 by the American Society for Pharmacology and Experimental Therapeutics.