Role of cannabinoid receptor 1 in spinal membrane in electroacupuncture-induced alleviation of morphine-triggered opioid-induced hyperalgesia in rats: relationship with phosphorylated ERK1/2
10.3760/cma.j.cn131073-20240917-00511
- VernacularTitle:脊髓膜蛋白CB1受体在电针缓解吗啡诱发大鼠OIH中的作用：与磷酸化ERK1/2的关系
- Author:
Yuxin ZHENG
1
;
Chao QIN
1
;
Yang YU
1
;
Yu BAI
1
;
Kai ZHANG
1
;
Yi CHEN
1
;
Yonghao YU
1
Author Information
1. 天津医科大学总医院麻醉科 天津市麻醉学研究所，天津 300052
- Publication Type:Journal Article
- Keywords:
Cannabinoid receptor 1;
Electroacupuncture;
Morphine;
Hyperalgesia;
MAP kinase signaling system
- From:
Chinese Journal of Anesthesiology
2025;45(5):581-585
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To evaluate the role of cannabinoid receptor 1 (CB1) in the spinal membrane in electroacupuncture (EA)-induced alleviation of morphine-triggered opioid-induced hyperalgesia (OIH) and the relationship with phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) in rats.Methods:Forty-eight clean-grade healthy male Sprague-Dawley rats, aged 2-3 months, weighing 240-260 g, in which intrathecal catheters were successfully implanted, were divided into 4 groups ( n=12 each) using a random number table method: normal saline group (NS group), morphine group (M group), morphine+ EA group (ME group), and morphine+ EA+ CB1 antagonist group (MEA group). The OIH model was established by intrathecal injection of morphine 15 μg (10 μl) twice a day for 7 consecutive days. The equal volume of normal saline 10 μl was given instead in NS group. EA of the " Yanglingquan" (GB34) and " Zusanli" (ST36) acupoints lasting 30 min was performed after the first administration of medication each day, with a current intensity of 2 mA and frequency of 2 Hz in ME group. In MEA group, morphine (15 μg) and CB1 antagonist AM251 30 μg (10 μl) were intrathecally injected twice a day for 7 consecutive days, with other treatments similar to those previously described in ME group. The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 1 day before administration (T 0) and on days 1, 3, 5 and 7 after administration (T 1-4). Rats were deeply anesthetized and sacrificed at T 3, 4 after administration, and the L 4-6 spinal cord tissues were collected for determination of the expression of membrane CB1, ERK1/2 and p-ERK1/2 by Western blot. Results:Compared with NS group, the MWT was significantly decreased and the TWL was shortened at T 3, 4 in M, ME and MEA groups, the expression of spinal membrane CB1 and p-ERK1/2 was significantly up-regulated at T 4 after administration in M group, and the expression of spinal membrane CB1 was significantly up-regulated at T 3, 4 after administration in ME and MEA groups ( P<0.05). Compared with M group, the MWT was significantly increased and the TWL was prolonged at T 3, 4, and the expression of p-ERK1/2 was down-regulated at T 4 after administration in ME group ( P<0.05), no significant change was found in MWT or TWL at T 3, 4 in MEA group ( P>0.05), and the expression of spinal membrane CB1 was significantly up-regulated at T 3, 4 after administration in ME and MEA groups ( P<0.05). Compared with ME group, the MWT was significantly decreased and the TWL was shortened at T 3, 4, and the expression of spinal membrane CB1 and p-ERK1/2 was up-regulated at T 4 after administration in MEA group ( P<0.05). Conclusions:Up-regulation of spinal membrane CB1 expression is involved in EA-mediated alleviation of morphine-induced OIH, which is associated with the inhibition of ERK1/2 phosphorylation in rats.
