T type calciumchannel activated by brain injury induces neural stem cell proliferation / 西安交通大学学报(医学版)

ABSTRACT

ABSTRACTObjective To investigate the mechanism and induction of T type calcium channel on neural stem cells after brain injury .Methods Adult mice brain injury model was established and divided into control ,sham operation ,surgery ,and surgery+mebefradil groups .Neural stem cells were separated from the subventricular zone (SVZ) and identified .Moreover ,we analyzed the results using MTT and neural stem cell sphere counting after adding different doses of mibefradil in culture medium ,respectively .Then we calculated the half maximal inhibitory concentration (IC50) of mibefradil on neural stem cells .Finally ,we analyzed the expression of Cav3 .2 in SVZ and the protein expressions of Cav3 .2 ,Cyclin A and caspase‐3 in neural stem cells by Western blot .Results In vivo , neural stem cell proliferation was increased in surgery group compared with that in control and sham‐operation groups .The proliferation of neural stem cells in surgery + mibefradil groups was significantly decreased compared with that in surgery group after mibefradil‐induced inhibition of T type calcium channel protein . In vitro , the formation of neural stem cell sphere was significantly inhibited after adding mibefradil .The cell growth ratio was significantly decreased when the concentration of mibefradil was above 5μmol/L .A values in 5 μmol/L ,10 μmol/L and 20μmol/L groups were significantly lower than those in control group (P<0 .05) .IC50 was 8 .93μmol/L .The protein expressions of Cyclin A and Cav3 .2 were inhibited while that of caspase‐3 was increased after mibefradil treatment .Conclusion Neural stem cell proliferation was enhanced by activating T type calcium channel after brain injury .