Linked Life Data

2583243

Source:http://linkedlifedata.com/resource/pubmed/id/2583243

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1990-1-3
pubmed:abstractText
In previous studies, we showed that cardiac muscarinic receptors (M2) are composed of two subgroups, M2 alpha and M2 beta, with different affinities for agonists and that the M2 alpha subgroup is coupled with inhibition of adenylate cyclase. We now studied which subgroup was responsible for the formation of inositol mono- (IP), bis- (IP2), tris- (IP3) and tetrakis- (IP4) phosphates in guinea pig heart. Carbachol (1 mM) significantly stimulated the formation of all four IPs in [3H]myoinositol-preloaded slices of guinea-pig ventricles. Acetylcholine (1 mM) also stimulated the formation of IP2, IP3 and IP4. However, oxotremorine (1 mM) only slightly stimulated the formation of IP2, and pilocarpine did not stimulate the formation of any IP. The pED50 values of carbachol for IP2 and IP3 formation were 3.76 and 4.23, respectively, which coincided with the pKd values of the low-affinity agonist binding site (L site) measured by competition of carbachol with [3H]quinuclidinyl benzilate [( 3H]QNB) binding while the pKd value for inhibition of adenylate cyclase coincided with the pKd value of the high-affinity agonist binding site (H site). Treatment of animals with pertussis toxin decreased the formation of IP2 and IP3 by carbachol to 66 and 54%, respectively, but resulted in complete inhibition of adenylate cyclase. These results suggested that muscarinic stimulation of the formation of IPs was manifested through a different receptor subgroup (M2 beta) and GTP binding protein different from those for inhibition of adenylate cyclase.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0014-2999
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
168
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
375-80
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
The H-L subgroup of guinea-pig cardiac M2 receptors (M2 beta) regulates inositol phosphate formation.
pubmed:affiliation
Department of Pharmacology I, Osaka University School of Medicine, Japan.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't