Effect of hydrogen-rich saline on autophagy in spinal neurons of rats with neuropathic pain / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the effect of hydrogen-rich saline on autophagy in the spinal neurons of rats with neuropathic pain.Methods Sixty pathogen-free male Sprague-Dawley rats,aged 8-l0 weeks,weighing 220-250 g,were randomly assigned into 3 groups (n=20 each) using a random number tablesham operation group (S group),neuropathic pain group (NP group),and hydrogen-rich saiine group (H group).Neuropathic pain was produced by chronic constriction injury of the sciatic nerve in the rats anesthetized with chloral hydrate.Hydrogen-rich saline 5 ml/kg was injected intraperitoneally once a day for 7 consecutive days in group H,while the equal volume of normal saline was given instead in S and NP groups.The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL)were measured at 1 day before operation (T0) and 1,3,5 and 7 days after operation (T1-4).The animals were sacrificed after measurement of pain threshold at day 7 after operation.L4-6 segments of the spinal cord were harvested to detect the expression of autophagy-related proteins microtubule-associated protein 1 light chain 3 Ⅱ (LC3 Ⅱ),Beclin-1 and p62 by Western blot.Results Compared with group S,the MWT was significantly decreased,and the TWL was significantly shortened at T2-4,and the expression of LC3 Ⅱ,Beclin-1 and p62 was significantly up-regulated at T4 in NP and H groups (P＜0.05).Compared with group NP,the MWT was significantly increased,and the TWL was significantly prolonged at T2-4,and the expression of LC3 Ⅱ and Beclin-1 was significantly up-regulated,and the expression of p62 was significantly down-regulated at T4 in group H (P ＜0.05).Conclusion The mechanism by which hydrogen-rich saline reduces neuropathic pain is related to induction of autophagy in the spinal neurons of rats.