Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1992-11-5
pubmed:abstractText
Specific receptors for oxytocin (OT) on intact luteal cells are demonstrated. Cultured cells from bovine corpora lutea (CL) at different stages (Days 3-5, 8-12, and 15-18 of the estrous cycle) were examined for OT receptors by a radioreceptor assay using the 125I-labeled OT antagonist [d(CH2)5,Tyr(Me)2,Thr4,Tyr-NH2(9)] -vasotocin. Binding specificity was demonstrated in displacement studies with various related peptides. Scatchard analysis revealed the presence of a binding site with an association constant of Ka = 2.6 x 10(9) M-1 and a capacity of 5.9 fmol/micrograms DNA. Additionally, in 50% of the experiments (n = 6) two different binding sites were observed. The Ka of the high-affinity site was 2.6 x 10(10) M-1; its capacity was 0.73 fmol/micrograms DNA. The low-affinity site had an apparent Ka of 4.9 x 10(8) M-1 and a capacity of 8.8 fmol/micrograms DNA. Observation of one versus two binding sites related neither to the assay conditions nor to the state of the individual CL used for the cell culture and therefore appeared to reflect individual variation within the OT receptor population. Significant binding of OT was observed at all luteal stages. OT binding was maximal at the mid-luteal stage (Days 8-12). We conclude that a direct action of OT on the bovine CL is mediated by the OT receptor, supporting the hypothesis that luteal OT plays an important physiological role in the regulation of progesterone release and/or other luteal functions in a paracrine or autocrine fashion.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-3363
pubmed:author
pubmed:issnType
Print
pubmed:volume
46
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1001-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Evidence for oxytocin receptors in cultured bovine luteal cells.
pubmed:affiliation
Department of Physiology, Technical University of Munich, Freising-Weihenstephan, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't