The proteolytic and membrane-bound enzymes (Na<sup>+</sup> K<sup>+</sup>-ATPase, Mg<sup>2+</sup>-ATPase and Ca<sup>2+</sup>-ATPase) were also decreased with increased apoptotic markers (Bcl2 Associated X Protein (Bax), cytochrome C, caspase 3 and 9) and decreased anti-apoptotic marker (B-cell lymphoma 2 (Bcl2)) in the brain of Cd-treated rats.