Linked Life Data

9746724

Source:http://linkedlifedata.com/resource/pubmed/id/9746724

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1998-12-7
pubmed:abstractText
One of the hypotheses to explain the mechanism of capacitation involves the loss of sperm membrane cholesterol. Here, we studied whether or not the major proteins of bovine seminal plasma designated as BSP-A1, -A2, -A3, and -30-kDa (collectively called BSP proteins), which are implicated in sperm capacitation, induce cholesterol efflux. When epididymal sperm were labeled with [3H]cholesterol and incubated with bovine seminal plasma (0.05-2%) or BSP proteins (20-120 microg/ml) for 8 h, the sperm lost [3H]cholesterol (3.6-fold and 3-fold, respectively). The same results in the presence of BSP-A1/-A2 were obtained (3.5-fold) by direct determination of cholesterol on unlabeled epididymal sperm. Analysis of efflux particles by ultracentrifugation on a sucrose gradient revealed a single symmetrical peak of radioactivity at 1.14 g/ml. Immunoblotting of the fractions obtained from size-exclusion chromatography of the efflux particles showed that a portion of the BSP proteins were associated with [3H]cholesterol. Heparin (12 microg/ml) alone did not stimulate cholesterol efflux. In contrast, high-density lipoprotein (HDL, 100 microg/ml) alone stimulated cholesterol efflux up to 3.1-fold after 8 h. When labeled epididymal sperm were preincubated for 20 min with BSP-A1/-A2 (120 microg/ml), washed, and incubated with HDL (100 microg/ml) for 8 h, the total cholesterol efflux of the sperm suspension was 51.8 +/- 5.0% compared to 39.3 +/- 1.2% when HDL alone was used. These results indicate that BSP proteins and HDL play an important role in the sperm sterol efflux that occurs during capacitation. Furthermore, the heparin-induced sperm capacitation did not involve the efflux of sperm membrane cholesterol.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-3363
pubmed:author
pubmed:issnType
Print
pubmed:volume
59
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
768-76
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Major proteins of bovine seminal plasma and high-density lipoprotein induce cholesterol efflux from epididymal sperm.
pubmed:affiliation
Department of Medicine, University of Montreal, and Guy-Bernier Research Center, Maisonneuve-Rosemont Hospital, Montreal, Quebec, Canada H1T 2M4.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't