Histopathology of the digestive gland-gonad complex of the marine prosobranch Littorina littorea exposed to cadmium

A histopathological investigation of the digestive gland-gonad complex of winkles that were experimentally exposed to sublethal concentrations of cadmium (Cd) was performed.The structural integrity of &gestive and basoph~lic cells of the digestive gland drastically changed such that both cell types became morphologically indistinguishable at the light microscope level.The volume density (VD) of hemocytes and pore cells located both around the stomach and in interstitial connective tissues were significantly increased due to Cd-exposure.Both hemocytic diapedesis across the epithelia of digestive tubules and stomach, and occasional disintegration of both epithelia appear to be related to Cd-exposure.The stress response caused by acclimation to laboratory conditions leads to the induction of spawning activity and masks the likely effect of Cd on the gonadal tissue.An intense hemocytic infiltration was observed in gonadal follicles of females exposed to 1 25 mg Cd I-' after 24 d.