Fig. 3. Changes in mitochondrial membrane potential (_m) in isolated oyster hemocytes exposed to different cadmium concentrations for 72 h as measured by TMRM staining. (A) Representative distributions of the TMRM fluorescence intensity of control and cadmium-exposed cells before or after treatment with a mitochondrial uncoupler (CCCP). (B) Quantitative graph of the data shown in A indicating the average TMRM fluorescence intensity in control cells and cells exposed to different cadmium concentrations before (-CCCP) and after (+CCCP) exposure to the mitochondrial uncoupler CCCP. The striped bar represents TMRM fluorescence in control hemocytes without digitonin treatment. Vertical bars represent S.E.M. ^*Values are significantly different from the control (0 µmol l^-1 Cd²⁺); values significantly different from the fluorescence intensity of the respective cell populations in the absence of CCCP (P<0.05; N=6-8).