PLATELET-ACTIVATING-FACTOR ACETYLHYDROLASE IN THE MALE REPRODUCTIVE-TRACT - ORIGIN AND PROPERTIES

The properties and origin of platelet-activating factor acetylhydrolas e- (PAF-AH)-like activity in the male reproductive tract were investig ated. Seminal plasma (SP) and serum were obtained from normal donors a nd infertile patients while prostatic fluid (PF), seminal vesicle flui d (SVF) and vas deferens fluid were collected at autopsy. PAF-AH-like activity was found in all fluids tested. The specific activity of the enzyme in SP and PF was twice that of PAF-AH in serum and 15-fold high er than that in SVF and vas deferens fluid. In SP, PAF-AH-like activit y was Ca++-independent, acid and heat labile, stable to freezing, not inhibited by phosphatidylcholine, but was inhibited by 10 mm disopropy lfluorophosphate (DFP) and 13 mm phenylmethylsulfonylfluoride (PMSF). These data indicate that the properties of the enzyme in SP are simila r to those reported for PAF-AH in serum. The variation in specific act ivity of PAF-AH in reproductive tract fluids suggest that there are ei ther activators of PAF-AH in SP or inhibitors in one or several of the other reproductive tract fluids.