Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1986-12-17
pubmed:abstractText
Neurotensin (NT) is now reasonably well established as a neurotransmitter or neuromodulator candidate in the CNS. In the present study, we characterized the NT receptors in dispersed cells from the anterior lobe of rat pituitary and investigated the involvement of both cyclic AMP and calcium in the release of prolactin (PRL) induced by NT receptor stimulation. The [3H]NT binding to membranes from anterior pituitary dispersed cells was found saturable and stereospecific. Scatchard analysis of the data gave a straight line indicating a Bmax value of 121 +/- 11 fmol/mg protein and a KD value of 1.4 +/- 0.2 nM. The calculated IC50 values for [3H]NT binding were 5.8 nM for NT, 7.8 nM for L-Phe-NT, and 3,000 nM for the pharmacologically inactive form D-Phe-NT. NT, up to a concentration of 1 microM, did not affect the cyclic AMP generating system in homogenates of anterior pituitary from male or lactating female rats. The same pattern of results was obtained for cyclic AMP formation in intact cells. NT and its analogs stereospecifically enhanced the influx of calcium into dispersed cells from rat anterior pituitary. The effect was time- and dose-dependent. It appeared to be associated with neurotransmitter-operated calcium channels since: preincubation of the cells with tetrodotoxin did not affect the increase in calcium influx induced by NT; concentrations of verapamil that counteract the influx of calcium induced by potassium lacked the capacity to modify the influx of calcium induced by NT; and NT lost its capacity to release PRL in the absence of extracellular calcium.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0022-3042
pubmed:author
pubmed:issnType
Print
pubmed:volume
47
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1682-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Identification of neurotensin receptors associated with calcium channels and prolactin release in rat pituitary.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't