Objective: To assess the relative importance of soluble (Sol) and membrane-bound (M-B) components of aminopeptidase (AP) activities in local functions of male and female gonads.
Design: Observational study.
Setting: University research.
Animal(s): Adult male and female Sprague-Dawley rats in the proestrous phase of the estrous cycle.
Intervention(s): Samples from the right testis and the whole right ovary were dissected after perfusion with saline. The Sol and M-B fractions were obtained from these samples.
Main outcome measure(s): Fluorometric measurement of Sol and M-B AP activities using arylamide derivatives as substrates.
Result(s): Highly significant differences between male and female gonads were observed. Sol AP activities showed a significant predominance in testes, whereas M-B AP activities were significantly higher in ovaries.
Conclusion(s): There was a discrepancy in the distribution of Sol and M-B AP activities between male and female gonads, which may imply a direct participation of sex steroids in AP activities. These results may reflect the relative importance of these enzymes in the testis and ovary and should be taken into account in evaluating the functional role of peptides locally produced in gonads.