title: Calcium-dependent and calcium-independent gelatinolytic proteinase activities of the rat ventral prostate and its secretion: characterization and effect of castration and testosterone treatment.
abstract: Calcium-dependent and calcium-independent proteinase activities were detected in extracts of rat ventral prostate and its secretion by use of gelatin-containing SDS-PAGE zymography. Ca(2+)-independent proteinase activities of 22, 26, and 73-79 kDa and Ca(2+)-dependent activities of 58, 63, and 66 kDa were found in the adult gland. The 26- (most intense activity of gland) and 22-kDa activities were present in secretion and were not expressed in the undifferentiated gland of the 10-day-old animal. The Ca(2+)-dependent activities were also present in the secretion, where the 63-kDa form was more prominently expressed than the 58- and 66-kDa bands. The Ca(2+)-dependent and Ca(2+)-independent proteinase activities both responded to a broad range of pH values in the incubation media. The 73-79-kDa Ca(2+)-independent activities were sensitive to benzamidine and the Ca(2+)-dependent activities were inhibited by EDTA and EGTA. Both Ca(2+)-dependent and Ca(2+)-independent proteinase activities responded to androgenic manipulations. Castration was followed by the appearance of a 35-kDa Ca(2+)-independent proteinase (at 2 days) and a 43-kDa Ca(2+)-dependent proteinase (at 4 days). In the Ca(2+)-independent proteinase group, the 73-79-kDa activities were increased somewhat and the 22- and 26-kDa activities decreased after castration. The Ca(2+)-dependent proteinases of 58, 63, and 66 kDa increased in activity with castration, but activity of the 58-kDa form decreased again at 7 days after castration. Treatment of animals upon castration for 4 days with hydrocortisone prevented these changes in proteinase activities whereas treatment with actinomycin D or tranexamic acid did not. Testosterone propionate replacement therapy of rats castrated for 16 days stimulated the activities of the 22- and 26-kDa and 73-79-kDa Ca(2+)-independent and the 58- and 63-kDa Ca(2+)-dependent proteinases with 4 days of therapy. The activities of the 35-kDa Ca(2+)-independent and the 43-kDa Ca(2+)-dependent proteinases were repressed with 8 days of testosterone treatment. Thus, individual proteinases show differential changes in activity during development and in response to androgenic manipulation: this suggests that in addition to proteinases which are secreted, others may be involved in intracellular functions or in mediating tissue organization changes.
authors.affiliation: Veteran's Administration Medical Center, Research Service, Minneapolis, MN 55417.
authors.forename: M J
authors.initials: MJ
authors.lastname: Wilson
authors.forename: M
authors.initials: M
authors.lastname: Strasser
authors.forename: M M
authors.initials: MM
authors.lastname: Vogel
authors.forename: A A
authors.initials: AA
authors.lastname: Sinha
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D010450:Endopeptidases / Q000378:metabolism*; D005780:Gelatin / Q000378:metabolism; D008297:Male; D009919:Orchiectomy; D011467:Prostate / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development; D051381:Rats; D011919:Rats, Inbred Strains; D013737:Testis / Q000502:physiology; D013739:Testosterone / Q000494:pharmacology
chemical_list: D013739:Testosterone; D005780:Gelatin; D010450:Endopeptidases; D002118:Calcium