Effect of dexmedetomidine on visceral pain in rats: the role of a2 adrenergic receptors in locus coeruleus
10.3760/cma.j.issn.0254-1416.2018.10.018
- VernacularTitle:右美托咪定对大鼠内脏痛的影响:蓝斑核α2肾上腺素能受体在其中的作用
- Author:
Chenmei PENG
1
;
Yufang LENG
;
Guangru ZHANG
;
Fengxiang GU
;
Jipeng LYU
Author Information
1. 730000,兰州大学第一医院麻醉科
- Keywords:
Dexmedetomidine;
Visceral;
Pain;
Locus coeruleus;
Receptors,adrenergic alpha-2
- From:
Chinese Journal of Anesthesiology
2018;38(10):1227-1229
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the effect of dexmedetomidine on visceral pain in rats and the role of α2 adrenergic receptors in locus coeruleus (LC).Methods Thirty-two healthy adult male SpragueDawley rats,weighing 250-300 g,were divided into 4 groups (n=8 each) using a random number table method:control group (group C),visceral pain group (group VP),dexmedetomidine group (group DEX) and α2-adrenergic receptor antagonist atipamezole group (group AP).α2-adrenergic receptor antagonist atipamezole 522 μg/kg was intramuscularly injected in group AP,and the equal volume of normal saline was given instead in C,VP and DEX groups.At 10 min after intramuscular injection,dexmedetomidine 10 μg/kg was injected via the tail vein in DEX and AP groups,and the equal volume of normal saline was given instead in C and VP groups.VP,DEX and AP groups received intraperitoneal injection of 0.9％ acetic acid 10 ml/kg to make the visceral pain model at 15 min after injection via the tail vein.The cumulative visceral pain score was recorded within 60 min after acetic acid injection.The number of c-fos positive cells in LC was detected by immunohistochemistry,and the content of norepinephrine (NA) in the spinal cord were detected by enzyme-linked immunosorbent assay at 2 h after acetic acid injection.Results Compared with group C,the cumulative visceral pain scores,the number of c-fos positive cells in LC and content of NA in the spinal cord were significantly increased in VP,DEX and AP groups (P＜0.05).Compared with group VP,the cumulative visceral pain scores,the number of c-fos positive cells in LC and content of NA in the spinal cord were significantly decreased in DEX and AP groups (P＜0.05).Compared with group DEX,the cumulative visceral pain scores,the number of c-fos positive cells in LC and content of NA in the spinal cord were significantly increased in group AP (P＜0.05).Conclusion Dexmedetomidine can alleviate visceral pain in rats,and the mechanism is partially related to activating α2 adrenergic receptors in LC.
