| Title: | "The skin of the male African catfish, Clarias gariepinus: a source of steroid glucuronides" |
| Author(s): | Ali SA; Schoonen WG; Lambert JG; Van den Hurk R; Van Oordt PG; |
| DOI: | 10.1016/0016-6480(87)90252-8 |
| ISSN/ISBN: | 0016-6480 (Print) 0016-6480 (Linking) |
| Abstract: | "Steroid metabolism in the skin of mature male African catfish, Clarias gariepinus, reared in the laboratory, was studied in vitro by tissue incubations with [3H]pregnenolone, [3H]dehydroepiandrosterone, [3H]17 alpha-hydroxyprogesterone, [3H]androstenedione, [14C]11 beta-hydroxyandrostenedione, and [3H]testosterone as precursors. While pregnenolone was not converted to any other steroid, dehydroepiandrosterone was transformed mainly to 5-androstene-3 beta, 17 beta-diol. The products of 17 alpha-hydroxyprogesterone incubations were 5 beta-pregnane-3 alpha,17 alpha-diol-20-one, 5 beta-pregnane-3 alpha,17 alpha, 20 beta-triol, and 5 beta-pregnan-17 alpha-o1-3,20-dione. The major steroids of androstenedione incubations were etiocholanolone, testosterone, and androsterone. Testosterone was converted mainly to etiocholanolone and androstenedione, and only small quantities of 11 beta-hydroxytestosterone, 11-ketotestosterone, and 11-ketoandrostenedione were the metabolites found in 11 beta-hydroxyandrostenedione incubation. These results demonstrated the presence of the enzymes 5 alpha- and 5 beta-reductases and 3 alpha-, 11 beta-, 17 beta-, and 20 beta-hydroxysteroid dehydrogenases in the skin. From enzymehistochemical results it appeared that the steroid conversions take place in the epithelial cells. Moreover, the presence of UDP-glucose dehydrogenase, an enzyme involved in the synthesis of glucuronic acid, in these cells indicates the possibility of steroid glucuronide formation. Indeed significant amounts of water-soluble steroid conjugates, particularly 5 beta-dihydrotestosterone- and testosterone-glucuronide, were found in the incubations with androstenedione and testosterone, indicating the presence of the UDP-glucuronosyl transferase in the catfish skin. In the light of these results, a role of the skin of African catfish in the production of semiochemicals having pheromonal properties is discussed" |
| Keywords: | 17-alpha-Hydroxyprogesterone Androstenedione/analogs & derivatives/metabolism Animals Catfishes/*metabolism Dehydroepiandrosterone/metabolism Glucuronates/metabolism Hydroxyprogesterones/metabolism In Vitro Techniques Male Pregnenolone/metabolism Skin/enz; |
| Notes: | "MedlineAli, S A Schoonen, W G Lambert, J G Van den Hurk, R Van Oordt, P G eng 1987/06/01 Gen Comp Endocrinol. 1987 Jun; 66(3):415-24. doi: 10.1016/0016-6480(87)90252-8" |
