Catabolism of phospholipids by chicken seminal components after storage.

The possibility of an activation of chicken spermatozoal phospholipase A2 during in vitro storage of undiluted semen was investigated. After storage for periods up to 24 hr at 5 C, the ability of semen to catabolize added phosphatidylcholine labeled on the 2nd carbon of glycerol with 14C oleic acid was assessed. Neither spermatozoa nor plasma from undiluted chicken semen was found to be capable of catabolizing added 14C labeled phosphatidylcholine, regardless of the storage period. No enzyme activity was evident when fresh semen was incubated under various assay conditions to determine the influence of cholic acid, calcium, and the type of phospholipid substrate on phospholipase A2 activity. The influence of spermatozoal protease activation on phospholipase A2 activity from undiluted chicken semen and from Naja naja naja was also investigated and found to have no influence on phospholipase A2 activity.