Linked Life Data

2158545

Source:http://linkedlifedata.com/resource/pubmed/id/2158545

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-5-30
pubmed:abstractText
This study was performed to determine the subtypes of histamine receptors that are involved in the electrophysiological, inotropic and biochemical responses to histamine in isolated rabbit papillary muscles. Histamine increased force of contraction and shortened action potential duration (APD) in a concentration-dependent manner. The former was antagonized by chlorpheniramine, a H1-antagonist, whereas the latter was blocked by cimetidine, a H2-antagonist. However, even when H1-receptors were blocked entirely by chlorpheniramine, histamine still produced a positive inotropic effect, an effect which was antagonized by cimetidine. On the other hand, when H2-receptors were eliminated by cimetidine, histamine caused a H1-receptor mediated APD prolongation. Carbachol attenuated the decrease in APD but not the increase in force of contraction caused by histamine. Cyclic AMP and cyclic GMP levels both were elevated significantly by histamine. The increase in cyclic AMP level induced by histamine was abolished by cimetidine, but not altered by chlorpheniramine, whereas the converse was true for the increase in cyclic GMP level. Additionally, histamine produced a significant stimulation of phosphoinositide hydrolysis as measured by [3H]inositol monophosphate accumulation, although its extent was far less than that produced by carbachol. The phosphoinositide response to histamine was blocked by chlorpheniramine. These data suggest that H1- and H2-receptors coexist in rabbit ventricles. Stimulation of H1- and H2-receptors with histamine independently sets off the biochemical responses linked specifically to the respective subtypes of histamine receptors. On the other hand, the inotropic and electrophysiological responses to histamine are governed predominantly by H1- and H2-receptors, respectively, and this results in an apparent restriction of the expression of the responses mediated by another subtype.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-3565
pubmed:author
pubmed:issnType
Print
pubmed:volume
253
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
250-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Inotropic, electrophysiological and biochemical responses to histamine in rabbit papillary muscles: evidence for coexistence of H1- and H2-receptors.
pubmed:affiliation
Department of Pharmacology, Hokkaido University School of Medicine, Sapporo, Japan.
pubmed:publicationType
Journal Article, In Vitro