PRESENCE OF PLATELET-ACTIVATING-FACTOR IN SQUIRREL-MONKEY (SAIMIRI-BOLIVIENSIS) SPERMATOZOA - SEASONAL DIFFERENCES

Platelet-activating factor (l-O-alkyl-2-acetyl-sn-glycero-3-phosphoryl - choline) (PAF) is a potent signaling phospholipid which has pleiotro pic biological properties in addition to platelet activation. PAF has been detected in the spermatozoa in a number of species. The concentra tion of PAF is inversely related to human spermatozoal quality. There are no reports on the presence of PAF in nonhuman primate spermatozoa. Therefore, the primary objective of this study was to determine if PA F is present in the spermatozoa from the squirrel monkey (which is a s easonal breeder). A second objective was to determine if PAF levels ch ange from the breeding to the nonbreeding season. Endogenous lipids we re extracted from mature Bolivian squirrel monkeys (Saimiri boliviensi s) spermatozoa and assayed for the presence of PAF by [I-125] radioimm unoassay. PAF was detected in all samples assayed. PAF levels were sig nificantly higher (P < 0.01) during the breeding season (mean: 3.58 ng /10(6) spermatozoa) than the nonbreeding season (mean: 0.76 ng/10(6) s permatozoa). The data demonstrate that PAF is present in squirrel monk ey spermatozoa, with higher levels found during the breeding season. A dditional studies are warranted to elucidate the role of PAF in sperma tozoa function. (C) 1998 Wiley-Liss, Inc.