Neuroprotective Effect of Clonidine on Primary Cultured Cortical Neurons in Rats Subjected to Oxygen-glucose Deprivation Injury

Objective To determine the neuroprotective effect of clonidine on primary cultured cortical neurons in rats exposed to oxygen-glucose deprivation( OGD) injury. Methods Cortical neurons cultured for 8 days were randomly assigned to the three groups: normal control group,model control group,and clonidine pretreatment group. OGD injury model was established by chemical hypoxia and glucose deprivation in incubation liquid for 4 h. Clonidine( 1.0,3.0,10 μmol·L-1) was added 24 h before OGD injury.Neuronal injury was evaluated by MTT staining and the release of lactate dehydrogenase( LDH).Results Under the microscope,primary cultured cortical neurons in normal control group presented great density,round size,smooth edge,and high diopter,The suvival rate of neurons and the percentage of LDH releasing were( 100. 00 ± 32. 12) % and( 100.00 ± 37. 51) %,respectively. After exposure to OGD injury,cortical neurons showed karyopyknosis,incomplete cell membranes,low diopters and a significant reduction in optical density of MTT staining. In addition,the suvival rate of neurons and the percentage of LDH releasing were( 53. 61 ± 7. 62) % and( 166. 07 ± 9. 65) % separately compared with normal control group.In the group with pretreatment of different concentrations of clonidine( 1.0,3.0,10 μmol·L-1),morphological changes induced by OGD injury were significantly reversed and optical density of MTT staining was dose-dependently raised. The percentages of survival neurons much higher than that of model control group were [( 67. 53 ± 10. 54) %,( 71. 50 ± 9. 79) % and( 87.48±5.29) %,separately]and the obvious reductions of LDH releasing were [( 136.45±25.72) %,( 130.92±24.94) % and( 121.63±32.68) %,respectively]. Conclusion Clonidine can exert neuroprotection against OGD-induced injury in primary cultured cortical neurons in rats.