Effects of cadmium and mercury on ovarian maturation in the red swamp crayfish, Procambarus clarkii.

In vivo mercury significantly inhibited ovarian maturation in the red swamp crayfish, Procambarus clarkii. 5-Hydroxytryptamine (5-HT) induced ovarian maturation in vivo. Cadmium and mercury inhibited this 5-HT-induced maturation. Ovarian explants incubated with mercury and either brain or muscle demonstrated significant inhibition of [14C]leucine incorporation into ovarian proteins compared to the corresponding groups incubated without mercury. In the absence of mercury the brain, which contains a gonad-stimulating hormone (GSH), induced significantly more incorporation of this amino acid than occurred in the ovaries incubated with muscle. These metals may have exerted their inhibitory effects by directly inhibiting protein synthesis in the ovaries, inhibiting 5-HT-stimulated GSH release, and preventing the ovaries from responding to this hormone.