17-ketosteroids and monodansylcadaverine

Dispersed mouse testicular interstitial cells were treated with the transglutaminase inhibitor monodansylcadaverine (500 microM) for 30 min. Subsequent incubation of the cells with [3H]pregnenolone increased formation of steroidogenic intermediates, tentatively identified as progesterone, 17 alpha-hydroxyprogesterone, and androstenedione, but decreased testosterone formation by monodansylcadaverine-treated cells. Measurement of 17-ketosteroid reductase activity (the enzyme that converts androstenedione to testosterone) demonstrated that monodansylcadaverine treatment caused a reversible, noncompetitive inhibition of this enzyme. These results suggest that transglutaminase catalyzed protein cross-links may influence the activity of 17-ketosteroid reductase.

Topics: 17-Hydroxysteroid Dehydrogenases; 17-Ketosteroids; Acyltransferases; Animals; Cadaverine; Diamines; Kinetics; Male; Mice; Mice, Inbred Strains; Testis; Transglutaminases