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PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
26
pubmed:dateCreated
1980-3-24
pubmed:abstractText
This communication presents evidence for the existence in the ovine testis of proteinaceous factors which suppress LH as well as FSH. Isolation of these factors has been achieved by using three different procedures: cytosol preparation, metaphosphoric acid extraction and ultrafiltration. Chromatography of cytosol or metaphosphoric acid extract on Sephadex G-75 resulted in separation into three protein fractions designated as G-75-I, II and III in order of their elution. When administered to castrated male rats, Fraction G-75-I suppressed circulatory levels of LH (53% inhibition, P less than 0.05) without altering FSH. The most retarded fraction, G-75-III, suppressed FSH (29% inhibition, P less than 0.001) without any concomitant change in LH. When fraction G-75-III was further fractionated on Sephadex G-25, three components were found and two, G-25-II and G-25-III, were biologically active. These fractions were homogeneous on polyacrylamide disc-gel electrophoresis. The FSH-suppressing factor (inhibin) was heat labile and susceptible to trypsin digestion, indicating that it is proteinaceous. Treatment with urea did not reveal any subunits. The molecular weight of this factor, as determined by gel filtration and SDS-urea gel electrophoresis was estimated to be around 1400-1500. The absence of sialic acid and the molecular weight data suggested that the isolated material was a simple protein and probably a small peptide. Gel filtration on Sephadex G-75 of the metaphosphoric acid extracts of liver, kidney, testis and ovary revealed an identical elution pattern for ovarian and testicular inhibin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0449-3087
pubmed:author
pubmed:issnType
Print
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
71-85
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1979
pubmed:articleTitle
Characterization of a gonadal factor involved in the control of FSH secretion.
pubmed:publicationType
Journal Article