Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1995-2-6
pubmed:abstractText
Pituitary adenylate cyclase activating polypeptide (PACAP) is a hypothalamic peptide that affects anterior pituitary cell function. This study examined the effects of PACAP on prolactin (PRL) release in vivo and on tyrosine hydroxylase (TH) activity in tuberoinfundibular dopaminergic neurons in vivo and in vitro. In ovariectomized rats, intravenous injection of PACAP increased circulating PRL levels 3-fold and TH activity in the stalk-median eminence (SME) by 30%. Incubation of the SME with 1 microM PACAP in vitro increased TH activity 2-fold. Intravenous infusion of ovine PRL (oPRL) by an osmotic mini-pump for 2 days in ovariectomized rats increased TH activity in the SME 1.7-fold and reduced circulating concentrations of endogenous rat PRL to 20% of control levels. PACAP induced a 4-fold rise in endogenous rat PRL levels in oPRL-treated rats and a 30% increase in TH activity that was additive to the elevation caused by hyperprolactinemia. In suckled lactating rats, PACAP did not alter circulating PRL levels or TH activity in the SME. When pups were removed from the dams for 4-5 h, systemic injection of PACAP stimulated PRL release without altering TH activity. However, PACAP, when administered in vitro, stimulated TH activity in the SME of lactating rats separated from their pups. These data indicate that PACAP may play a role in augmenting PRL release in female rats. The PACAP-induced rise in PRL release is modest and not due to a decrease in tuberoinfundibular dopaminergic neuronal activity. PACAP increases TH activity in the tuberoinfundibular dopaminergic neurons, possibly by a direct action on nerve terminals within the median eminence.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-8993
pubmed:author
pubmed:issnType
Print
pubmed:day
29
pubmed:volume
655
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
17-24
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Pituitary adenylate cyclase-activating polypeptide (PACAP) increases prolactin release and tuberoinfundibular dopaminergic neuronal activity.
pubmed:affiliation
Department of Physiology, University of Kansas Medical Center, Kansas City 66160-7401.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.