Effect of intrathecal dexmedetomidine on expression of substance P and c-fos in spinal dorsal horns of rats with visceral pain
10.3760/cma.j.issn.0254-1416.2018.08.017
- VernacularTitle:鞘内注射右美托咪定对内脏痛大鼠脊髓背角P物质和c-fos表达的影响
- Author:
Guangru ZHANG
1
;
Yufang LENG
;
Xinghua LYU
;
Chenmei PENG
;
Fengxiang GU
;
Jipeng LYU
Author Information
1. 730000,兰州大学第一医院麻醉科
- Keywords:
Dexmedetomidine;
Injections,spinal;
Viscera;
Pain;
Substance P;
Proto-oncogene proteins c-fos
- From:
Chinese Journal of Anesthesiology
2018;38(8):960-963
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the effect of intrathecal dexmedetomidine on expression of sub-stance P (SP) and c-fos in the spinal dorsal horns of rats with visceral pain. Methods Thirty-two clean-grade healthy adult male Sprague-Dawley rats, weighing 250-300 g, were divided into 4 groups ( n=8 each) using a random number table method: control group (C group), visceral pain group (VP group), dexmedetomidine group (D group) and dexmedetomidine plus atipamezole group (DA group). VP, D and DA groups received intraperitoneal injection of 0. 9% acetic acid 10 ml∕kg to establish the model of visceral pain, while group C received the equal volume of normal saline instead. At 10 min before the model was es-tablished, dexmedetomidine 20 μl (1μg∕kg) and dexmedetomidine 1μg∕kg plus atipamezole 1μg∕kg (20μl) were intrathecally injected in D and DA groups, respectively, and the equal volume of normal saline 20μl was given instead in C and VP groups. Visceral pain index ( VPI) was recorded at 1 h after intraperito-neal injection, and then rats were sacrificed, and the dorsal horns of the spinal cord ( L4-6 ) were removed for determination of the expression of SP and c-fos by immunohistochemistry. Results Compared with group C, VPI was significantly increased, and the expression of SP and c-fos was up-regulated in VP, D and DA groups (P<0. 05). Compared with group VP, VPI was significantly decreased, and the expression of SP and c-fos was down-regulated in D and DA groups (P<0. 05). Compared with group D, VPI was signifi-cantly increased, and the expression of SP and c-fos was up-regulated in group DA ( P<0. 05) . Conclusion Intrathecal dexmedetomidine reduces the visceral pain through inhibiting the expression of SP and c-fos in the spinal dorsal horns, which is related to the α2-adrenergic receptor in spinal dorsal horns of rats.