Abstract: | Deoxyribonuclease (DNase) activity was examined in the whole and two split fractions of human seminal fluid from normospermic, oligozoospermic, and azoospermic origins as well as in sonicates of isolated sperm after freezing and thawing of samples and at various pH values of substrates. The method consisted in the measurement of digested areas in plates containing herring sperm deoxyribonucleic acid (DNA). No correlation was found between DNase activity (875 +/- 22 (SE) ng/ml) and seminal fluid quality. The enzyme activity was significantly lower in the second split portion (764 +/- 43 ng/ml) as compared to the first (971 +/- 41 ng/ml). Sonicates of washed sperm were inactive. It is suggested that DNase activity derives from the epididymis and possibly from the vas deferens where it participates in the decomposition of DNA from dead cells. |