Linked Life Data

3973828

Source:http://linkedlifedata.com/resource/pubmed/id/3973828

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1985-4-25
pubmed:abstractText
The number of muscarinic cholinergic receptors detected with [3H]quinuclidinyl benzilate (QNB) was constant in embryonic chick heart membranes but increased 2.5-fold by 3 days posthatching; the KD for [3H]QNB did not change. The affinities of the muscarinic receptors for agonists, as determined in in vitro [3H]QNB competition experiments, differed during development. The IC50 values were lowest for 10- to 14-day embryonic heart receptors, intermediate for 18- to 20-day embryonic receptors and highest for 3- to 7-day newborn heart receptors. These apparent differences in agonist affinity were not overcome by guanine nucleotides or monovalent cations alone, but were greatly diminished in the presence of a combination of guanylylimidodiphosphate plus NH4+. Modeling of [3H]QNB/oxotremorine competition curves indicated the presence of three agonist affinity states in membranes from embryonic heart and two in newborn hearts. The KD values for oxotremorine increased during development. The proportion of receptors displaying the highest affinity for oxotremorine was constant at all ages tested whereas the proportion displaying the lowest affinity decreased from 16% in membranes from 12-day embryonic hearts to zero in newborn hearts. The physiological significance of the differences in the properties of the receptors was investigated by assessing their ability to attenuate adenylate cyclase. The efficacy of agonists to attenuate basal adenylate cyclase increased 1.5-fold after birth, whereas the potency of agonists to produce this effect was similar at all ages tested.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-3565
pubmed:author
pubmed:issnType
Print
pubmed:volume
232
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
795-801
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Differences in the properties of muscarinic cholinergic receptors in the developing chick myocardium.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't