Testis Incubation and Androgen Biosynthesis

Androgen biosynthesis (secretory capacity for androgen precursors and testosterone) is assessed by incubation of the testis in vitro with hCG 250 mU for 3 hours. 

The testes of each rat were decapsulated and gently washed in tissue culture medium (TCM) 199 (Sigma biochemicals M 2154) previously gassed with car-bogen (95 % O2, 5 % CO2). Each decapsulated testis 

Group means are calculated, and the significance of differences between groups is assessed by analysis of variance and appropriate tests of significance. 

This method can be applied ex vivo, in repeated-dose studies for clarification of mechanisms of action, and as part of subacute toxicology studies. The immediate processing of the decapsulated testis is an advantage when compared with the assays based on a enzymatic dispersion of Ley dig cells. 

The stimulation test can be performed as a single-dose test in rats during the treatment period, preferably three to four days before the end of the study, or as a single dose test in satellite groups of animals. Stimulation of testosterone in rats can be indirect via the release of luteinizing hormone by injection of LHRH (gonadore- 

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