Objective:To explore the role of 6-CYANO-2,3-DIHYDROXY-7-NITROQUIN OXALINE (CNQX) in different types of synapse secretion.Methods:The spontaneous mEPSCs and eEPSCs at different extracellular concentrations of CNQX in cultured cortical or hippocampal neurons were recorded respectively.Results:The half inhibitory concentration (IC50) of CNQX in evoked neurotransmitter release was significantly higher than that of spontaneous release,indicating that the spontaneous neurotransmitter release was more sensitive to CNQX.No apparent difference was observed between cortical and hippocampal cells,suggesting that the blocking effect of CNQX was similar in different brain regions.Conclusion:CNQX might have differential regulating mechanisms between excitatory spontaneous and evoked neurotransmitter release,but without brain regions specificity.

ObjectiveTo investigate the effects of exogenous transforming growth factor β1 on the apoptosis of nerve cells and its functions following spinal cord injury in rats.MethodsNinety-six male Wistar rats were randomly divided into 4 groups:group A(control group),group B(spinal cord injured group),group C (spinal cord injuried +TGF-β1 treated group),group D (spinal cord injuried +anti-TGF-β1 treated group).The rat model of spinal cord injury was found by the Allen's method.In group C and D,drugs were injected into subarachnoid cavity continuously by minipump.The changes of spinal cord were observed by HE staining.Nerve cells apoptosis was detected by transferase-medi-ated dUTP nick end labeling (TNUEL) method and the expression of cell apoptosis factor Fas by immunohistochemistry staining.Functional recovery of hind limbs was measured by Basso-Beattie-Bresnahan locomotor open field behavioral rating test.ResultsThe expression of TGF-β1and Fas increased following spinal cord injury.The amount of TGF-β1and Fas reached the peak 7days and 1day after injury.The apoptosis of neuron had increased and peaked 8 hours after injury.The apoptosis of neuroglia cells had increased and peaked 7 dayss after injury.The slight changes was found in spinal cord in group C.Both of the number of apoptosis of nerve cells and expression of the apoptosis factor (Fas) decreased significantly; compare with group B and D.The BBB score was higher in group C than that in group B and D.ConclusionTGF-β1 can improve the functional recovery of spinal cord by inhibiting the nerve cell apoptosis after the spinal cord injury.