Linked Life Data

2123441

Source:http://linkedlifedata.com/resource/pubmed/id/2123441

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1991-1-17
pubmed:abstractText
Serum concentrations of PRL and GH increase and decrease, respectively, during the progression from nonpregnancy through lactation. However, it is unknown whether the secretory capacities and/or relative abundance of cells that release PRL or GH are altered during these physiological states. In the present study anterior pituitaries from adult virgin, gestating, and early or late lactating female rats were dispersed with trypsin and subsequently assayed for PRL and GH release using reverse hemolytic plaque assays. We found that the relative abundance of PRL-secreting cells was greater and that of GH cells lower in pituitaries from lactating females than in those from virgins. Moreover, the relative amounts of both PRL and GH released per cell were diminished in gestating and lactating females. For PRL, this decrease could be accounted for by an increase in the number of cells that released small quantities of hormone. We then performed simultaneous plaque assays to determine whether the shifts in the relative proportions of PRL and GH secretors were due to changes in the percentages of cells that secrete each hormone alone or in the fraction that releases both PRL and GH concurrently. Variations in both single and dual hormone-secreting cells appear to contribute to the overall fluctuations in the relative abundance of PRL and GH cells during these physiological transitions. We conclude that the additional PRL secretors present during lactation may arise from cells that previously released only GH, and that this functional interconversion of GH and PRL secretors might involve an intermediate cell type, the mammosomatotrope.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
127
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2789-94
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Is the mammosomatotrope a transitional cell for the functional interconversion of growth hormone- and prolactin-secreting cells? Suggestive evidence from virgin, gestating, and lactating rats.
pubmed:affiliation
Department of Anatomy and Cell Biology, Medical University of South Carolina, Charleston 29425.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.