Effects of mild hypothermia on proNGF apoptosis pro-signal following cerebral ischemia and reperfusion

Abstract

Objective To observe the expressional changes of pro nerve growth factor(proNGF)apoptosis pro-signal factors after cerebral ischemia and reperfusion and discuss the protective effect of mild hypothermia on the brain injury. Methods The randomly chosen female SD rats weighing(220±10)g were divided into normal control group(Group A),cerebral isehemia and reperfusion group (Group B)and mild hypothermia group(Group C).Groups B and C were divided into 3,6 and 9 hours subgroups(eight rats per group).TUNEL methods was used to detect the apoptotic cells in the cortex after cerebral ischemia and reperfusion and treatment with mild hypothermia.The reverse transcription polymerase chain reaction(RT-PCR)was used to detect the expression changes of proNGF,Sortilin and P75gene in the cortex. Results (1)The apoptotic cells were increased with time in the Group B(P<0.05)and were more than those in the Group C in the same time point(P<0.05).(2)There found expression of all factors at all time points in three groups,which was increased with time(P<0.05).(3)The content of every factor at each time point in the Group C was less than that in the Group B(P<0.05). Conclusions (1)Mild hypothermia can decrease the apoptosis after ischemia and reperfusion injury.(2)The cell apoptosis induced by proNGF plays a very important role in the COUrse of cerebral ischemia and reperfusion injury.(3)Mild hypothermia can decrease the expression of apoptosis pro-signal to alleviate the cell apoptosis and protect the brain from ischemia and reperfusion. Key words: Reperfusion injury,brian; Hyhothermia,induced; Nerve growth factor; Apoptosis