Effect of Mild Hypothermia on the Apoptosis-related Factors in Rats after Resuscitation

  Objective  To study the effect of mild hypothermia after resuscitation on rat neuronal apoptosis and its gene expression.

  Methods  Sixty healthy male SD rats were equally randomized into two groups:normal temperature group(T=37℃±0.5℃) and mild hypothermia group (T=33℃±1.0℃).A rat model of asphyxial cardiac arrest and cardiopulmonary resuscitation was established. The neurological functions were assessed using neurological deficit score (NDS) 12 and 24 hours after the restoration of spontaneous circulation. Also, the expressions of the apoptosis-inducing factor (AIF), caspase-3, and Fas mRNA were detected using reverse transcription-polymerase chain reaction (RT-PCR) at 0, 2, 6, 12, and 24 hours, respectively.

  Results  Compared with the normal temperature group, the mild hypothermia group had significantly higher NDS at 12 and 24 hours(P < 0.05) and lower number of apoptotic brain cells at 6, 12, and 24 hours(P < 0.05). The mRNA expressions of AIF and caspase-3 at each time point and Fas at 6, 12, 24 hours were significantly reduced after resuscitation in mild hypothermia group(P < 0.05).

  Conclusion  Therapeutic hypothermia after resuscitation may improve NDS and thus protect brain by inhibiting expressions of apoptotic genes including AIF, caspase-3, and Fas.