Isoflurane enhances the expression of cytochrome C by facilitation of NMDA receptor in developing rat hippocampal neurons in vitro.

This study examined the effects of clinically relevant concentrations of isoflurane on the amplitude of NMDA receptor current (I(NMDA)) and the expression of cytochrome C in cultured developing rat hippocampal neurons. The hippocampi were dissected from newborn Sprague-Dawley rats. Hippocampal neurons were primarily cultured for 5 days and then treated with different concentrations of isoflurane [(0.25, 0.5, 0.75, 1 minimum alveolar concentration (MAC))]. The peak of I(NMDA) was recorded by means of the whole cell patch clamp technique. The cytochrome C level was detected by Western blotting and quantitative real-time PCR. Our results showed that isoflurane (0.25, 0.5, 0.75 and 1 MAC) potentiated the amplitude of I(NMDA) by (116 ± 8.8)%, (122 ± 11.7)%, (135 ± 14.3)% and (132 ± 14.6)%, respectively, and isoflurane increased the mRNA expression of cytochrome C in a concentration-dependent manner. The cytochrome C mRNA expression reached a maximum after 0.5 MAC isoflurane stimulation for 6 h (P<0.05). It was concluded that isoflurane enhances the expression of cytochrome C in cultured rat hippocampal neurons, which may be mediated by facilitation of NMDA receptor.