title: Application of liposomal membranes to the analysis of the triggering mechanism of sperm acrosomal reaction.
abstract: The analysis of the triggering mechanisms of the sperm acrosomal reaction was attempted by using multilamellar liposome model membranes. The permeability of liposomes composed of egg lecithin, cholesterol and dicetylphosphate was increased by addition of the acrosome reactive substance which was obtained from the jelly coat of the sea urchin, Hemicentrotus pulcherrimus. An identical but more rapid response was also observed with liposomes containing sialoglycosphingolipids isolated from spermatozoa of the sea urchin. CA++ ions enhanced the reaction with both types of liposomes. The multilamellar liposomes were found to be useful as a model membrane of the sperm acrosomal reaction, and an involvement of sialoglycosphingolipids in the sperm acrosomal reaction was suggested.
mesh_terms: D000177:Acrosome / Q000502:physiology*; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002463:Cell Membrane Permeability; D002784:Cholesterol / Q000494:pharmacology; D008055:Lipids / Q000494:pharmacology; D008081:Liposomes / Q000032:analysis / Q000378:metabolism / Q000494:pharmacology*; D008297:Male; D010713:Phosphatidylcholines / Q000494:pharmacology; D012617:Sea Urchins; D013094:Spermatozoa / Q000502:physiology*
chemical_list: D008055:Lipids; D008081:Liposomes; D010713:Phosphatidylcholines; D002784:Cholesterol; D002118:Calcium