Amidolytic activities and prostate-specific antigen in human seminal plasma

The amounts of protein measured by absorbance at 280 nm, succinyl-L-alanyl- L-alanyl-L-prolyl-L-leucine-p-nilroanilide (Suc-Ala-Ala-Pro-Leu-pNA), d-val yl-cyclohexyl-alanyl-L-arginine-p-nitroanilide (Val-CHA-Arg-pNA), and gluta myl-L-phenylalanine-p-nitroanilide (Glu-Phe-pNA) amidolytic activities, and prostate-specific antigen (PSA) were measured in human seminal plasma (HSP ) samples separated from the semen of 46 cases, including 13 cases of azoos permia and 33 cases of normozoospermia showing either good or poor quality of liquefaction. There was a highly significant correlation between the con centrations of all amidolytic enzyme activities studied and the concentrati on of PSA in HSP samples (p < .01). The HSP sample volume showed a relative ly good negative coefficient of correlation to all items measured (p < .01) with the exception of protein concentration. The Suc-Ala-Ala-Pro-Leu-pNA, Val-CHA-Arg-pNA, and Glu-Phe-pNA amidolytic activities in azoospermia HSP s amples were 2.33, 1.68, and 1.43 times higher, respectively, than those of normozoospermia samples showing good quality liquefaction. After the additi on of morphologically purified human sperm to HSP sample of azoospermia cas es, the Suc-Ala-Ala-Pro-Leu-pNA amidolytic activity in the HSP sample of az oospermia was not decreased for up to 18 h incubation, while the number of motile human sperm gradually declined, and no motile human sperm were detec ted after 18 h of incubation. The high Suc-Ala-Ala-Pro-Leu-pNA amidolytic a ctivity in HSP samples of azoospermia cases did not result From a lack of m otility.