Responses of seminal vesicle and testicular ?-glucuronidase and ?-N-acetylglucosaminidase to testosterone and some metabolites inHeteropneustes fossilis (Bloch)

✍ Scribed by Chowdhury, I. ;Joy, K.P.

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 72 KB
• Volume: 290
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1128

✦ Synopsis

Abstract

Intraperitoneal administration of testosterone for 20 days produced differential effects on β‐glucuronidase and β‐N‐acetylglucosaminidase (β‐Glc) activity in seminal vesicle (SV) and testis of the catfish Heteropneustes fossilis in preparatory phase (March). The lower dosages of 0.25 and 0.5 μg/g body weight (BW) of the steroid did not alter enzyme activity, and the higher dosages (1.0 and 2.0 μg/g BW) inhibited it significantly. Under in vitro conditions, addition of ascorbate and fructose (0.5–100 mM) to the incubation medium influenced enzyme activity differentially. At concentrations 0.5 and 1.0 mM, both fructose and ascorbate were ineffective except for the inhibition of testicular β‐Glc activity in the 1.0 mM ascorbate group. At higher concentrations (10, 50, and 100 mM), ascorbate inhibited enzyme activity in a concentration‐dependent manner. At 10 mM concentration of fructose, only testicular β‐Glc activity was inhibited, but at higher concentrations (50 and 100 mM), activities of both enzymes decreased uniformly in a concentration‐dependent manner. The addition of glucose had no significant effect on the enzyme activity at any of the concentrations tested. The results suggest that the inhibitory effect of testosterone on enzyme activity may be mediated through androgen‐dependent metabolites, such as fructose and ascorbate. J. Exp. Zool. 290:777–782, 2001. © 2001 Wiley‐Liss, Inc.