The mode of action of carp gonadotropin on the stimulation of androgen production by carp testis in vitro

Carp gonadotropin (cGTH) can stimulate carp testis to produce androgen in vitro. This action can be mimicked by dibutyryl cAMP (Bt₂ cAMP) and prostaglandins (PG). Bt₂ cAMP can enhance the androgen production when submaximal doses of cGTH are used but cannot do so when maximal dose of cGTH is used. PG F_2α is more effective than PG E₁ and E₂. Both the inhibitors of RNA and protein synthesis can interfere the stimulatory effect of cGTH. Actinomycin D has 87% while cycloheximide has 100% inhibition. The stimulatory effect of cGTH is much more dependent on de novo protein synthesis than on RNA synthesis. In addition, steroidogenesis inhibitors, glutethemide, metyrapone, and spirocyanoketone, can also inhibit the stimulatory effect of cGTH on androgen production.