Linked Life Data

7895920

Source:http://linkedlifedata.com/resource/pubmed/id/7895920

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1995-4-27
pubmed:abstractText
Previous studies have shown that disruption or damage to the seminiferous tubules by radiation, antiandrogen, vitamin A deficiency or experimental cryptorchidism causes Leydig cell hypertrophy and hyperplasia, suggesting that Sertoli cells secrete a mitogenic factor(s) that stimulates Leydig cell proliferation. To study the possible paracrine regulation of Leydig cell proliferation by Sertoli cells, highly purified Leydig cells and Sertoli cells were co-cultured in a two-chambered co-culture system. Our results revealed that co-culture of immature rat Sertoli cells with Leydig cells stimulated Leydig cell DNA synthesis by 19-fold, increased cell number by about 3.9-fold and increased the labeling index from 0.5% to 15.8%. In addition to these changes, co-culture reduced Leydig cell testosterone formation and luteinizing hormone (LH) receptor levels, and dramatically altered the morphology of Leydig cells. The addition of concentrates from Sertoli cell conditioned medium (SCCM) mimicked these biological effects. The Leydig cell mitogenic activity in SCCM was trypsin sensitive and inactivated by boiling for 2 h, suggesting that it is a protein. However, it was resistant to acid and dithiothreitol. The molecular weight of this putative factor(s) is above 10 kDa. The responsiveness of Leydig cells to this mitogenic protein(s) decreased with age, whereas the secretion of this protein(s) by Sertoli cells in culture did not change with age. The addition of 10 ng/ml of follicle stimulating hormone (FSH) dramatically decreased the mitogenic activity in SCCM, indicating that the secretion of this mitogenic factor(s) is inhibited by FSH. This paracrine factor(s) may be as yet an unidentified testicular growth factor(s) because it differs in molecular weight, stability and other characteristics from all previously reported Sertoli cell-produced or expressed growth factors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0303-7207
pubmed:author
pubmed:issnType
Print
pubmed:volume
106
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
99-109
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
A Sertoli cell-secreted paracrine factor(s) stimulates proliferation and inhibits steroidogenesis of rat Leydig cells.
pubmed:affiliation
Research Service, Dorn Veterans' Hospital, Columbia, SC.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't