Role of transient receptor potential ankyrin 1 in dorsal root ganglion neurons in development of diabetic neuropathic pain in rats

Abstract

Objective To evaluate the role of transient receptor potential ankyrin 1 (TRPA1) in the dorsal root ganglion neurons in the development of diabetic neuropathic pain (DNP) in rats.Methods Twenty-four Sprague-Dawley rats with DNP were randomly divided into 3 groups (n-=8 each) using a random number table:DNP group,TRPA1-specific siRNA group (siRNA group) and TRPA1-negative siRNA group (NC group).Another 8 Sprague-Dawley rats with normal blood glucose served as control group (C group).In siRNA group,TRPA1-specific siRNA 45 μl was injected intrathecally.In NC group,TRPA1-negative siRNA 45 μl was injected intrathecally.In DNP and C groups,normal saline 45 μl was injected intrathecally.On 2nd day after intrathecal administration,the lumbar segment (L4-6) of the dorsal root ganglions was removed for determination of the expression of TRPA1 mRNA.On 7,14,21 and 28 days after intrathecal administration (T1-4),MWT was measured.Results Compared with DNP group,TRPA1 mRNA expression was down-regulated in siRNA and C groups.Compared with DNP group,and MWT was significantly decreased at T1.2 in siRNA group,MWT was decreased at T1-3 in NC group,MWT was increased at T1-4 in group C.Compared with siRNA group,MWT was significantly increased at T1-4 in group C.MWT was significantly higher at T1~ in group C than in NC group.Conclusion TRPA1 in the dorsal root ganglion neurons is involved in the development of DNP in rats. Key words: Transient receptor potential channels; Posterior horn cells; Diabetic neuropathies