Effect Of Melatonin On Bcl-2 ,bax Expression In Hippocampal And Oxidative Stress In Rat With Chronic Intermittent Hypoxia

ObjectiveThis study was to observe the changes of neuronal apoptosis , and protein expressions of bcl-2 and bax in hippocampus after therapy with melatonin in rats exposed to chronic intermittent hypoxia.MethodsMale SD rats were randomly divided into 3 groups, a control group A, a CIH group B, a MT therapeutic group C . Colorimetric method was used to measure the levels of MDA and SOD . Immunohistochemistry was done for observing proteins expressions of bcl-2 and bax. TUNEL was used to detect the neuron apoptosis rate .Neurons was observed under a transmission electron microscope .ResultsThe level of MDA in MT therapeutic group (0.6760±0.0687) was significantly lower than in CIH group (1.7±0.17) ,(F=12.876,P<0.01). the level of SOD in MT group (46.92±5.66) was increased As Compared with CIH group (32.288±2.984),, (F=11.2525, P<0.01). TUNEL positive neurons/mm~2 in the hippocampus in groups A, B and C were 0.0675±0.0125, 0.335±0.0532, and 0.193±0.0202 respectively, (F=64.138 ,P=0.000). Bcl-2 positive neurons/mm~2 in hippocampus in groups A, B and C were 0.142±0.0178, 0.0968±0.0173 and 0.220±0.029 (F=64.138 , P<0.05), and those of bax were 0.176±0.012, 0.222±0.0256 and 0.135±0.00688respectively (F=34.759,P<0.05)。 ConclusionCIH could cause Oxidative stress and free radicals ,decrease the expression of bcl-2, increase the expression of bax and result in neuron apoptosis in rats hippocampus. Melatonin has the ability of neuroprotective effects in rats exposed to chronic intermittent hypoxia by relieving the oxidant stress injury and up-expression bcl-2 and down-expresion bax...