ABSTRACT
<p><b>OBJECTIVE</b>To evaluate effect of acute cadmium administration on mitochondria from rat kidney.</p><p><b>METHODS</b>24 male Sprague-Dawley (SD) rats were randomly divided into four groups. Four groups of rats were injected with saline, 0.6, 1.2, and 1.8 mg/kg weight subcutaneously, once daily, for 5 days, respectively. Ultrastructural change of rat kidney mitochondria was observed, and respiration function, membrane potential, mitochondria swelling, and superoxide level were determined.</p><p><b>RESULTS</b>Ultrastructural changes included matrix vacuolation, swelling and condensation of mitochondria. In group of 1.8 mg/kg body weight, the oxygen consumption rate during state 3 respiration [(6.25 +/- 0.61) nmol/L O2 x min(-1) x mg(-1)] and RCR value (2.45 +/- 0.23) were significantly lower than those of control group [(9.66 +/- 1.16) nmol/L O2 x min(-1) x mg(-1)] (P < 0.05), indicating respiration inhibition. The membrane potential and superoxide level of the same group were 85.89% +/- 3.82% and 116.33% +/- 3.06% of control values (P < 0.05), respectively.</p><p><b>CONCLUSIONS</b>Acute cadmium administration can cause rat kidney mitochondrial damage in a dose-effect manner, including inhibition of respiration, dissipation of membrane potential, swelling of mitochondria matrix. Such damage might be related to the increase of mitochondrial free radical.</p>