Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1992-1-27
pubmed:abstractText
Small and medium-sized gonadotropes may enlarge and produce more LH in order to contribute to the proestrous surge. To test this hypothesis, dispersed pituitary cells from cycling female rats were separated by centrifugal elutriation into small, medium, and large fractions and labeled for LH beta antigens or mRNA (by in situ hybridization with a biotinylated oligonucleotide probe complementary to sequences encoding amino acids 28-40). The percentage of cells bearing LH beta mRNA in the pituitary cell population increased from 6 +/- 0.4% in the evening of diestrous day 2 to 16 +/- 0.7% in the morning of estrus (average +/- SEM). Over 80% of these labeled cells were large or small subtypes. The proportion of small gonadotropes labeled with LH beta mRNA declined from 43 +/- 3% at metestrus to 29 +/- 1% on the evening of proestrus as the proportion of medium-sized gonadotropes labeled for LH beta antigens (15 +/- 1%) or mRNA (17 +/- 1%) increased to 25 +/- 2% or 38 +/- 2%, respectively. Because the overall percentage of immunoreactive LH cells did not change after diestrus, small LH cells may have enlarged or increased their density to join the medium-sized pool. During proestrus, the proportion of large immunoreactive LH gonadotropes increased from 41 +/- 2% to 65 +/- 2% (by the morning of estrus) as the proportion of small or medium-sized LH cells declined to 17-18 +/- 1%, suggesting further increases in size or density. These data suggest that small or medium-sized gonadotropes are activated during early diestrus to enlarge and produce LH beta. They contribute to the increased number of cells in medium-sized and large fractions in proestrous or estrous rats. The predominance of the smaller subtypes during metestrus and diestrus suggests that LH gonadotropes may revert to a smaller or lighter subset to await activation during the next cycle.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
130
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
335-44
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Recruitment and maturation of small subsets of luteinizing hormone gonadotropes during the estrous cycle.
pubmed:affiliation
Department of Anatomy and Neurosciences, University of Texas Medical Branch, Galveston 77550.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't