Therapeutic function of intravenous monosialoganglioside GM-1 on neurotoxicity of intrathecally administered bupivacaine in rats / 临床麻醉学杂志

ABSTRACT

Objective To investigate the therapeutic effects of intravenous monosialo ganglio-sides(GM-1)on neurotoxicity of intrathecally administered bupivacaine in rats and its possible mecha-nism.Methods One hundred and eight adult male Sprague-Dawley rats,weighing 280-300 g,were randomly divided into 3 groups (n=36 each)sham operation group (group sham),group saline and group GM-1.Neurotoxicity model was performed by injecting 0.12μl/g body weight of bupivacaine at concentrations of 5% via an implanted intrathecal catheter at 90-minute intervals for 4.5 h in groups saline and GM-1.After observing 24 h,group GM-1 was administered GM-1 30 mg/kg by intrave-nous injection for 7 days,once a day;while groups saline and sham received equal volume of normal saline.The recovery of the locomotor function was evaluated with Basso,Beattie and Bresnahan (BBB)and tail-flick latency(TFL)before injection bupivacaine and days 1,3,5,7,14,28 after in-jection,TFL was converted to the percent maximum possible effect (%MPE).Six rats were sacri-ficed in each group at each time point,and spinal cord was taken to examine histological injury scores by light and electron microscopy at the L3 level,and neuron caspase-3 expression was evluated using immunohistochemistry and RT-PCR.Results Compared with group saline,%MPE,histological inju-ry score and caspase-3 mRNA expression were decreased on days 7,14 and 28;Caspase-3 protein ex-pression was decreased on days 5,7,14 and 28;while BBB score was higher on days 14 and 28 in group GM-1 (P < 0.05 ).Compared with group sham,% MPE,histological injury score,caspase-3 mRNA and protein expression in groups GM-1 and saline were significantly higher,while BBB score was lower on 1,3,5,7,14 and 28 d after injection (P <0.05).Conclusion GM-1 can promote neuro-functional recovery after bupivacaine neurotoxicity in rats through the possible mechanism of down-regulating neuron caspase-3 expression.