Table 7_Sublethal cadmium exposure disrupts cardiac function and tissue structure in zebrafish larvae.pdf

This study aimed to evaluate the effects of sublethal cadmium exposure on cardiac function and on brain and heart tissues in zebrafish (Danio rerio) larvae, utilizing photoplethysmography as a rapid, non-invasive approach. Larvae (1 day post-hatching) were exposed for five days to cadmium sulfate at concentrations of 0.005, 0.025, and 0.05 mg/L under controlled laboratory conditions.

Cardiac activity was assessed twice a day using a non-invasive photoplethysmography-based technique. Histological analyses of brain and heart tissues were conducted using standard fixation, sectioning, and staining protocols. At the highest cadmium concentration, histological examination revealed neuronal degeneration in brain tissue and thinning of the cardiac wall.