Cadmium as an endocrine disruptor: Correlation with anterior pituitary redox and circadian clock mechanisms and prevention by melatonin

► A low dose of Cd suppresses 24-h rhythms in plasma prolactin (PRL), luteinizing hormone, thyrotropin, and corticosterone. ► Cd increases pituitary expression of PRL and lipid peroxidation during photophase. ► Cd disrupts 24-h rhythms in pituitary redox enzyme and clock gene expression. ► Melatonin counteracts most effects of Cd as an endocrine disruptor.