Mercury effects on glutathione in the freshwater crayfish(Procambarus clarkii). In vivoandin vitrostudy

Abstract

Procambarus clarkii, the American red crayfish, is used as species for the study of the effect of mercury contamination. The glutathione (GSH) system has been involved in mercury toxicity in different species. This system has been partially characterized in different organs of Procambarus clarkii (Almar et al., Comp. Biochem. Physiol. 89B, 471., 1988), and shown to be sensitive to other heavy metals poisoning (Almar et al., Comp. Biochem. Physiol. 87C, 433, 1987; Almar et al., Biochem. Soc. Trans. 16, 23, 1988). Mercuric chloride treatment with 1/10 of the previously reported LC50 for Procambarus clarkii does not decrease the glutathione content of midgut and green glands since the stoichiometric amount necessary for that is much higher. Some kinetic characteristics of the GSH S‐transferase activity of the cytosolic fraction of the midgut gland (also called hepatopancreas) are presented (pH‐and temperature‐dependence).