Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5 Pt 1
pubmed:dateCreated
1988-1-6
pubmed:abstractText
Two radioligands, 125I-labeled substance P (125I-SP) and 125I-labeled substance K (125I-SK), were used to characterize the kinetics and stoichiometry of binding of mammalian tachykinins [substance P (SP), substance K (SK), and neuromedin K (NK)] to smooth muscle cells isolated from the longitudinal muscle layer of guinea pig intestine. Specific binding of 125I-SP and 125I-SK was rapid, saturable, reversible, and temperature dependent. Binding attained 63-70% of steady-state binding within 1 min, coincidentally with the time of optimal contraction. The order of potency with which mammalian tachykinins and the SP antagonist, [D-Pro2, D-Trp7,9]SP, inhibited the binding of both radioligands was identical: SP greater than SK greater than NK greater than [D-Pro2, D-Trp7,9]SP, implying preferential interaction with a site that had highest affinity for SP. SK was 2-3 times, NK 3-4 times, and [D-Pro2, D-Trp7,9]SP 7-23 times less potent than SP (IC50 0.36 nM). Except for NK, the order of potency was similar to that for contraction of isolated muscle cells. The existence of binding sites with even higher affinity was suggested by the ability of muscle cells to contract in response to concentrations as low as 10(-13) M. These binding sites were not detectable at the concentration of radioligands used. It was concluded that a SP receptor is the only tachykinin receptor subtype present on intestinal muscle cells of the guinea pig.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
253
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
G666-72
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Receptors for substance P on isolated intestinal smooth muscle cells of the guinea pig.
pubmed:affiliation
Department of Medicine, Medical College of Virginia, Richmond 23298-0001.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't