The Influence Of Propofolum On The Mitochondria Membrane Potential Of Hippocampus Neurocytes

Objective:To investigate the protection and mechanism of propofolum to the cerebral ischemia-reperfusion injuries,by observing the changes of neurocyte morphous,methyl thiazolyl tetrazolium(MTT) and mitochondria membrane potential of rat's hippocampus after hypoxia and resupplying oxygen injury.Method:1.The hippocampus neuron's primary culture of the embryos rats which gestational age were 17-18days.2.The groups of experiment:The hippocampus cells which have been cultured for 6-Tdays were devided into normal control(C),model group after hypoxia-reoxygenation(M),and propofolum group(P).Samples were taken from model group and propofolum group at 0,4,8,12,24 hours after hypoxia(labelled T1,T2,T3,T4, T5,respectively).3.The morphological changes of hippocampus in each group were observed by means of inverted phase contrast microscope.4.The the influence of propofolum on survival rate and chondriosome function of hippocampus neurocytes were evaluated by MTT.5.Rh123 was used as fluorescent probe to mark the chondriosome of hippocampus neurocytes.Both the quantitative and qualitative analysis of the mitochondria membrane potentials(MMP) were evaluated by flow cytometer and laser confocal microscopy respectively.Results:1.The cultured hippocampus neurocytes remains good morphous and activity in control group.2.Vacuolus,axonotmesis,rupture of axons and fragments were found in neurons of model group.In propofol group mild engorgement and vacuolus was found in individual neurons.The proportion of injuried cells was lower than that of model group. 3.The survival rate and chondriosome function of hippocampus neurocytes evaluated by MTT showed significant difference between the survival rate of propofolum group and model group(P＜0.05) at T1,T2,T3,T4 after resupplied oxygen but not found in T5.4.The MMP of model group(224.09) decreased sharply compared to both normal control(353.84) and propofolum group(264.60) immediately after hypoxia.The MMP of both P group and M group decreased smoothly at the later 4 time points,and the values of propofolum group were higher than M group conspicuously for each time point.The result of the mean fluorescent intenisity by laser confocal microscopy revealed that the green fluorescent light darkened and reduced in quantity,while erythrophil increased gradually in both group M and P.This was more obviously in M group,especially at 0 hour and 24hours after resupplied oxygen.While in propofolum group the variaty trend was more moderate.Conclusion:1.The variation of MMP happens early at 2 hours after hypoxia.In that it can be as the early mark of apoptosis.2.Propofolum can increase the survival rate of hippocampus neurons after the ischemia-reperfusion injuries,improve the function of chondriosome,enhance the transportation of proton pump in mitochondrial inner membrane and keep stable membrane potential difference of chondriosome.The protection of bolus propofolum to nerve cells shows conspicuous time effect,following the time prolongation the effect goes weak.