Linked Life Data

1907102

Source:http://linkedlifedata.com/resource/pubmed/id/1907102

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1 Pt 1
pubmed:dateCreated
1991-8-27
pubmed:abstractText
We have previously shown that adenosine, acting at an A1 receptor, contracts the smooth muscle of virgin guinea pig uterus (M. A. Smith, I. L. O. Buxton, and D. P. Westfall. J. Pharmacol, Exp. Ther. 247: 1059-1063, 1988) and is not coupled to the expected inhibition of adenylate cyclase (M. A. Smith, J. L. Silverstein, D. P. Westfall, and I. L. O. Buxton. Cell. Signal. 1: 357-365, 1989). To probe the importance of contractile actions of adenosine in uterine smooth muscle and to further characterize the signal transduction pathway involved in A1-receptor action, we have studied the adenosine receptor and its coupling in pregnant guinea pig myometrium. Adenosine agonist and antagonist radioligands bind to saturable sites of the A1 subtype homogeneously distributed in the smooth muscle of pregnant guinea pig uterus. Agonist competition of antagonist radioligand binding in both the absence and presence of guanine nucleotide reveals high and low agonist affinity states of the receptor. Pretreatment of tissues with pertussis toxin (PTx) shifts the high-affinity sites to a lower affinity but does not affect low-affinity sites, whereas agonist competition in the presence of guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S) is indistinguishable from the control, which is consistent with coupling of A1 receptors to both PTx-sensitive and PTx-insensitive GTP-binding proteins. Adenosine receptor inhibition of adenylate cyclase activity is prevented after pretreatment of the tissue with PTx, whereas increased inositol phosphate production is not. The data presented here are consistent with coupling of the A1 receptor to dual effectors in the pregnant state of the smooth muscle. The unique action of an A1 receptor to contract mammalian smooth muscle and the appearance, only in the pregnant state, of coupling to adenylate cyclase inhibition suggest a role for adenosine in parturition biology.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/1,3-dipropyl-8-cyclopentylxanthine, http://linkedlifedata.com/resource/pubmed/chemical/Adenosine, http://linkedlifedata.com/resource/pubmed/chemical/Adenylate Cyclase, http://linkedlifedata.com/resource/pubmed/chemical/Adenylate Cyclase Toxin, http://linkedlifedata.com/resource/pubmed/chemical/GTP-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Guanosine 5'-O-(3-Thiotriphosphate), http://linkedlifedata.com/resource/pubmed/chemical/Inositol Phosphates, http://linkedlifedata.com/resource/pubmed/chemical/N(6)-cyclohexyladenosine, http://linkedlifedata.com/resource/pubmed/chemical/Pertussis Toxin, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Purinergic, http://linkedlifedata.com/resource/pubmed/chemical/Type C Phospholipases, http://linkedlifedata.com/resource/pubmed/chemical/Virulence Factors, Bordetella, http://linkedlifedata.com/resource/pubmed/chemical/Xanthines
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
261
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
E141-50
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Smooth muscle adenosine A1 receptors couple to disparate effectors by distinct G proteins in pregnant myometrium.
pubmed:affiliation
Department of Pharmacology, University of Nevada School of Medicine, Reno 89557.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't