In ram spermatozoa treatment with Ca2+ and A23187 or ionomycin stimulated the release of
arachidonic acid (20: 4) and exocytosis of the acrosome in a time-and concentration-
dependent manner. Diacylglycerol did not appear to be the source of 20: 4. On the other
hand, generation of 20: 4 was significantly correlated with breakdown of
phosphatidylcholine, phosphatidylserine, and phosphatidylethanolamine under a variety of
conditions, thus indicating that 20: 4 release was due to phospholipase A2 activity …