OBJECTIVETo evaluate the determination of seminal acid phosphatase (ACP) and gamma-glutamyltranspeptidase (gamma-GT) activity, and analyze the correlation between seminal ACP or gamma-GT and semen parameters.

METHODSACP and gamma-GT activities in 133 samples of seminal plasma were measured. Two of the samples were randomly selected for intra-assay, one for the detection of ACP activity and the other for gamma-GT activity. And another four were selected the same way for the same purpose, two for the detection of ACP activity and the other two for gamma-GT activity. The semen volume, pH, sperm concentration, motility, and grade-a and -b motility were analyzed by CASA system and so were the correlation between seminal ACP or gamma-GT activity and semen parameters.

RESULTSThere was significant positive correlation between ACP and gamma-GT activities (r = 0.570, P = 0.000). The intra-CV of ACP was 13.72%, and inter-CVs of ACP were 13.80% and 15.49%. The intra-CV of gamma-GT was 7.68%, and inter-CVs of gamma-GT were 7.76% and 9.73%. Both seminal ACP and gamma-GT activities had significant negative correlation with pH (r = -0.330, P = 0.000 vs r = - 0. 388, P = 0.000). There was obvious correlation between gamma-GT activity and sperm concentration (r = 0.165, P = 0.045), but not between ACP activity and sperm concentration (r = 0.048, P = 0.546). Neither of seminal ACP and gamma-GT activity was correlated with sperm motility, grade-a and -b motility, semen volume, abstinence time and age.

CONCLUSIONThe precision of the measurement of gamma-GT activity in seminal plasma was higher than that of ACP. The correlation between seminal gamma-GT activity and semen parameters was similar to that between seminal ACP activity and semen parameters. Thus, the determination of gamma-GT activity was a more reliable marker than that of ACP activity for the evaluation of prostate function.