Effect of trivalent and hexavalent chromium on carbohydrate metabolism of a freshwater field crab, Barytelphusa guerini

The in vivo toxic impact of chromium in its two forms (trivalent and hexavalent) on glycogen metabolism in the tissues of freshwater field crab Barytelphusa guerini was studied. In a sublethal long-term exposure of 30, 60 and 90 days, the depletion of glycogen and glucose levels reflected in the activity of glycogenphosphorylases 'a' and 'ab'. A tissue specific and time- dependent variation in tissue glucose reserves parelleled the progressive accumulation of haemolymph sugars. Trivalent and hexavalent chromium induced alterations in metabolite levels and in enzyme activities in the tissues. The magnitude of responses were found more in the hexavalent form than in trivalent form.