Abstract
Summary
Suspensions of dimyristoyl and dipalmitoyl phosphatidylcholine vesicles bearing 10 to 40 (w/w)% cholesterol inhibited the fertilizing ability of uterine-capacitated rabbit spermatozoa at concentrations of 1 to 10 mg of lipid/ml. Recovery of fertilizing ability by treated sperm cells was observed following insemination into the uterus 5 to 6 hr before ovulation. Vesicles lacking the sterol were not inhibitory under the conditions employed. Suspensions of cholesterol (0.4 to 4 mg of sterol/ml) without phospholipid, in contrast, inhibited fertilization. Implication of cholesterol in sperm decapacitation by seminal plasma membrane vesicles is discussed in terms of these results.
I am indebted to Mr. R. Byrne and Mrs. N. Davis for their helpful assistance. The electron micrographs were prepared by Mr. K. Bedigian. Financial support was received from NIH Contract No. 1-HD-3-2781.
Get full access to this article
View all access options for this article.