Abstract
We used the Sandwich enzyme-linked immunosorbent assay method to measure clusterin concentrations in the sera and seminal fluid of 88 infertile men. We also investigated changes in the clusterin concentration in the seminal fluid after ejaculation. The results were as follows. 1. No significant differences in serum clusterin concentration were found among patients with normozoospermia/ (N group), oligozoospermia/ (O group), idiopathic azoospermia/ (IA group) and obstructed azoospermia/ (OA group) . 2. The clusterin concentration in seminal fluid changed with the passage of time in cases with or without sperm. The clusterin concentration declined marked in each group after ejaculation. However, there were no significant differences in the changes in clusterin concentration with the passage of time among the different groups. 3. The clusterin concentration in the seminal fluid among all cases was 5.9 fold higher than that in serum 30 minutes after ejaculation, 3.5 fold higher 1 hour after ejaculation, and 2.5 fold higher 2 hours after ejaculation. 4. No significant differences were observed between the clusterin concentration and the IgG concentration in the seminal fluid with the passage of time. These results suggest that the decreases in clusterin concentration in the seminal fluid with the passage of time might be the result of formation of complexes with complement factors, of clusterin degradation, or of interaction with other substances. The mechanism of the clusterin decreases in seminal fluid should be studied further.
