The Study On Regulatory Mechanism Of GABA-activated Currents In Isolated Dorsal Root Ganglion Neurons In Rats By Midazolam

Objective: To observe the midazolam on chronic constriction injury (CCI) of sciatic nerve chronicpressure caused by nerve pathological pain rats, DRG neurons on the GABAAreceptor activationcurrent, the effect of midazolam in the spinal cord level, possible mechanisms of analgesia.Methods:(1) using the hot plate experiment testing the CCI group, control group and lower heatshrinkable foot reflexology incubation period of change.(2) using whole-cell patch clamp techniquerecords CCI model group side, control side, the normal group of GABAAreceptor activation currentamplitude on DRG neurons.(3) midazolam pre perfusion at different times of GABA causedmembrane current adjustment.(4) record (0.03~100μmol/L) midazolam on normal group and CCIgroup DRG neurons on the GABAAreceptor activation current adjustment.Results:(1) lower limbs pyrocondensation foot reflex latency CCI group was obviously shortened.(2) GABA (0.03~100μmol/L) of the DRG neurons can make produce concentration dependence ofthe inward current, and the inward currents can be selective antagonist bicuculline GABAAreceptors(100μmol/L) is interrupted.(3) CCI group (0.1~1000μmol/L) GABA activated current amplitudewere significantly less than control group and normal control group (P <0.01).(4) midazolam(0.03~100μmol/L) the concentration dependence increases the GABAAreceptor mediated membranecurrent, in3.0μmol/L when the enhanced role is the most significant,(P <0.05).(5) perfusionmidazolam40s enhancement effect of GABA activated membrane current when the most obvious.(6)(3μmol/L) midazolam that GABA concentration-response curve upward reaction.(7) Midazolam theCCI group and normal control group of GABAAreceptor activation current were enhanced, and CCIgroup increased more obviously, the difference was statistically significant.Conclusions: midazolam GABAAreceptor of DRG neurons have enhancement effect, and CCIgroup increased more obviously. And GABAAreceptors are involved in the presynaptic inhibition,thus enhanced the function of GABAAreceptor may be one of the mechanism of analgesia in thespinal cord level...