Effects of sevoflurane on dendritic development and the expression of collapsin response mediator proteins in the hippocampus of developing rats / 中华行为医学与脑科学杂志

ABSTRACT

Objective To investigate the effects of sevoflurane ( Sevo ) on dendritic development and the expression of collapsin response mediator proteins ( CRMP ) in the hippocampus of developing rats. Methods Twenty-four neonatal Sprague Dawley (SD) rats at postnatal day 7 (P7) were randomly divided into control group or sevoflurane group ( 12 rat pups for each group) .Rats in the control group were exposed to air for 4 h,whereas rats in the sevoflurane group were exposed to 2.8%sevoflurane for 4 h.The hippocam-pus of some rats were collected,and the expressions of CRMP1,CRMP2 and CRMP4 proteins and phospho-rylation of CRMP2 protein at Ser522,Thr514 and Thr555 were detected by Western blot 6h after exposure ( n=6) .The rest rats were housed till P30,the expression of CRMP1,CRMP2 and CRMP4 proteins in the hip-pocampus were detected by Western blot ( n=6) and the morphology changes of dendrites in the dentate gy-rus ( DG) of hippocampal neurons were detected by Golgi-Cox Staining ( n=6) .Results The expression of CRMP1,CRMP2 and CRMP4 proteins of rats at P7 in the sevoflurane group was decreased by 35.0%( P=0.004) ,27.5%( P=0.015) and 12.0%( P=0.003) ,respectively,and the phosphorylation of CRMP2 pro-tein at Ser522 and Thr514 in the sevoflurane group were increased by 68.3%( P<0.01) ,74.5%( P<0.01) , respectively,6 h after exposure compared with control rats.However,the phosphorylation of CRMP2 protein at Thr555 was not significantly changed after sevoflurane exposure.At P30,both total dendrite length ( P=0.001) and the dendrites length at level 2 and 3 ( P=0.033, P<0.01,respectively) were shorter and the dendritic branching at 120,140 and 160 μm rings in Sholl analysis were less ( P=0.009, P=0.028, P=0.048,respectively) for rats in the sevoflurane group,compared with control rats.There were no significant changes at the expressions of CRMP1,CRMP2 and CRMP4 proteins.Conclusion Sevoflurane inhibits the development of dendrites in the hippocampal DG area of developing rats,which may be related to inhibition of CRMP1,CRMP2 and CRMP4 proteins expression and hyperphosphorylation of CRMP2 Ser522 and Thr514.