Effect of dexmedetomidine on remifentanil-induced miniature excitatory postsynaptic currents mediated by NMDA receptors in spinal dorsal horn neurons of rats
10.3760/cma.j.issn.0254-1416.2017.08.009
- VernacularTitle:右美托咪定对瑞芬太尼诱导大鼠脊髓背角神经元NMDA受体mEPSCs的影响
- Author:
Zhe SUN
1
;
Yuan YUAN
;
Ying HE
;
Zhifen WANG
;
Guolin WANG
;
Yonghao YU
Author Information
1. 300052,天津医科大学总医院麻醉科天津市麻醉学研究所
- Keywords:
Dexmedetomidine;
Piperidines;
Receptors,N-methyl-D-aspartate;
Hyperalgesia;
Spinal cord
- From:
Chinese Journal of Anesthesiology
2017;37(8):931-934
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the effect of dexmedetomidine on remifentanil-induced miniature excitatory postsynaptic currents (mEPSCs) mediated by N-methyl-D-aspartate (NMDA) receptors in spinal dorsal horn neurons of rats.Methods Thirty male Sprague-Dawley rats,aged 14-18 days,weighing 50-60 g,were used in the study.Their lumbar segments of the spinal cord were immediately removed and sliced.A total of 180 slices were selected and divided into 5 groups (n=36 each) using a random number table:blank control group (group C),remifentanil group (group R),low-dose dexmedetomidine group (group L),moderate-dose dexmedetomidine group (group M) and high-dose dexmedetomidine group (group H).Spinal cord slices were incubated in artificial cerebrospinal fluid (ACSF) for 90 min in group C.Spinal cord slices were incubated for 90 min in ACSF with remifentanil at the final concentration of 4 nmol/L in group R.Spinal cord slices were incubated for 90 min in ACSF with remifentanil at the final concentration of 4 nmol/L and dexmedetomidine at the final concentrations of 2,4 and 6 nmol/L in L,M and H groups,respectively.The whole-cell patch-clamp technique was used to record the amplitude and time interval of NMDA receptors-mediated mEPSCs.Results Compared with group C,the amplitude of mEPSCs was significantly increased,and the time interval of mEPSCs was shortened in the other 4 groups (P＜ 0.05).Compared with group R,the amplitude of mEPSCs was significantly decreased,and the time interval of mEPSCs was prolonged in L,M and H groups (P＜0.05).Compared with group L,the amplitude of mEPSCs was significantly decreased,and the time interval of mEPSCs was prolonged in M and H groups (P＜0.05).Compared with group M,the amplitude of mEPSCs was significantly decreased,and the time interval of mEPSCs was prolonged in group H (P ＜ 0.05).Conclusion Dexmedetomidine weakens remifentanil-induced enhancement in the function of NMDA receptors in spinal dorsal horn neurons probably via the presynaptic and postsynaptie mechanisms in rats.
