Sayer Ji
Founder of GreenMedInfo.com

Subscribe to our informative Newsletter & get Nature's Evidence-Based Pharmacy

Our newsletter serves 500,000 with essential news, research & healthy tips, daily.

Download Now

500+ pages of Natural Medicine Alternatives and Information.

n/a
Abstract Title:

[Electroacupuncture intervention relieves pain possibly by promoting MOR endocytosis in locus coeruleus in bone cancer pain rats with morphine tolerance].

Abstract Source:

Zhen Ci Yan Jiu. 2019 Mar 25 ;44(3):161-9. PMID: 30945497

Abstract Author(s):

Ren-Yi Shi, Tao-Fang Fu, Yang-Qian Cai, Jun-Ying Du, Jun-Fan Fang, Jian-Qiao Fang, Yi Liang

Article Affiliation:

Ren-Yi Shi

Abstract:

OBJECTIVE: To observe the effect of electroacupuncture (EA) on pain behavior and expression ofµ-opioid receptor (MOR) and Rab5 (an important protein molecule for internalization of MOR) in the locus coeruleus (LC) region in bone cancer pain (BCP) rats with morphine tolerance (MT), so as to explore its mechanisms underlying improvement of BCP and MT.

METHODS: The present study included two parts. In the first part, 23 female SD rats were randomized into sham BCP (=6), BCP (=9) and BCP+MT (=8) groups, and in the second part, 61 female SD rats were randomized into 5 groups: sham BCP (=11), BCP (=11), BCP+MT (=13), BCP+MT+EA (=13) and BCP+MT+sham EA (=13). The BCP morphine tolerance (BCP+MT) model was established by injection of 10 µL of human Walker 256 breast cancer cells (MRMT-1 breast cancer cells, 1 x10cells/µL) into the bone marrow cavity at the upper part of the left tibia and intraperitoneal injection of morphine hydrochloride (10 mg/kg, once per 12 h, for 11 successive days). On day 21 after inoculation, EA (2 Hz/100 Hz, 0.5-1.5 mA, increasing 0.5 mA every 10 min) was began to applied to bilateral"Zusanli"(ST30) and"Kunlun"(BL60) immediately after the first intraperitoneal injection of morphine. The treatment was performed for 30 min every time, once daily for 7 successive days. The paw withdrawal threshold (PWT) was detected before and 10, 11, 21, 22, 24, 26 and 28 days after inoculation. The immunoactivity of MOR and Rab5 proteins in the LC region was detected by immunofluorescence histochemistry.

RESULTS: In the first part of the study, at the 10day after inoculation of cancer cells, the PWT of the BCP and BCP+MT groups was significantly lower than that of the sham BCP group (<0.05), suggesting a success of BCP model. From day 11 to 19 after inoculation (during injection of morphine), the PWTs of the BCP+MT group were significantly higher than those of the BCP group (<0.01), and on day 21, the PWT of the BCP+MT group was similar to that of the BCP group (>0.05) but significantly lower than that of the sham BCP group (<0.01), suggesting a success of MT. H.E. staining showed a large quantity of MRMT-1 cancer cells in the bone marrow cavity in both BCP and BCP+MT groups. In the second part of the study, the decreased PWTs from 10to 28day after inoculation were significantly increased on day 22, 24, 26 and 28 in the BCP+MT+EA group relevant to the BCP, BCP+MT and BCP+MT+sham EA groups (<0.01). The ratios of MOR and Rab5 positive () cells and MOR/Rab5of the left LC region were significantly lower in the BCP and BCP+MT groups than those of the sham BCP group (<0.01), but were considerably higher in the BCP+MT+EA group than those in the BCP, BCP+MT and BCP+MT+sham EA groups (<0.01). The ratios of Rab5and MOR/Rab5cells of the BCP+MT group were significantly lower than those of the BCP group (<0.05). No significant changes were found in the ratios of MORand Rab5cells and MOR/Rab5cells after BCP+MT+sham EA in comparison with the BCP+MT group (>0.05).

CONCLUSION: EA intervention can relieve pain and MT in bone cancer pain rats with MT, which may be related to its effects in increasing MOR expression and promoting endocytosis of MOR in LC region.

Study Type : Animal Study

Print Options


Key Research Topics

Sayer Ji
Founder of GreenMedInfo.com

Subscribe to our informative Newsletter & get Nature's Evidence-Based Pharmacy

Our newsletter serves 500,000 with essential news, research & healthy tips, daily.

Download Now

500+ pages of Natural Medicine Alternatives and Information.

This website is for information purposes only. By providing the information contained herein we are not diagnosing, treating, curing, mitigating, or preventing any type of disease or medical condition. Before beginning any type of natural, integrative or conventional treatment regimen, it is advisable to seek the advice of a licensed healthcare professional.

© Copyright 2008-2019 GreenMedInfo.com, Journal Articles copyright of original owners, MeSH copyright NLM.