低能量激光对大鼠背根神经节持续受压后痛觉敏感及TRPV4表达的影响

目的:观察低能量激光对大鼠背根神经节持续受压(chronic compression of the dorsal root ganglion,CCD)后痛觉敏感及脊髓背角内TRPV4表达及分布的影响.方法:选取健康雄性Wistar大鼠36只,分为空白组、CCD组、激光组各12只,各组均给予常规饲养.激光组在CCD后第4...

The effect of low-level laser on the pain sensitivity and the expression of TRPV4 after chronic compression of the dorsal root ganglion in rats

Objective:To observe the effect of low-level laser on the pain sensitivity and the expression and distribution of TRPV4 in the dorsal horn of the spinal cord after continuous compression of the dorsal root ganglia(CCD)in rats.Method:Thirty-six healthy male Wistar rats were divided into three groups,blank group,CCD group and laser group.In the laser group,810 nm low-level laser,output power 150 mW,10 min/time,was given to L4/L5 spinal cord segment through skin on the 4 th day after CCD for 7 days.Before and on the 4 th,7 th and 11 th day after operation,the mechanical withdrawal threshold and the thermal withdrawal latency were measured.On the 11 th day after operation,Western Blot was used to detect the protein expression of TRPV4 in spinal dorsal horn,and the distribution of TRPV4 positive cells was detected by immunofluorescence technique.Result:Compared with the blank group,the mechanical withdrawal threshold and the thermal withdrawal latency in the CCD group decreased on the 4 th day significantly(P<0.01),with no changes through 7 th to 11 th day after operation.The mechanical withdrawal threshold and the thermal withdrawal latency in the laser group decreased as the same as in CCD group on the 4 th day significantly(P<0.01).They increased gradually and significantly on the 7 th and 11 th day(P<0.01),but still less than before operation(P<0.01).Compared with the blank group,the expression of TRPV4 in the dorsal horn of the spinal cord and the number of TRPV4 positive cells in the CCD group was significantly up-regulated(P<0.01),but they are nearly the same with the blank group in the laser group.Conclusion:Low-level laser treatment can reduce the expression of TRPV4 protein and reduce the number of TRPV4 positive cells in spinal dorsal horn of rats after CCD,reduce the number of TRPV4 positive cells,so as to lower the central sensitization of TRPV4 to neuropathic pain,and alleviate the pain sensitivity caused by CCD.