[骨边缘电针通过调节吗啡耐受的骨癌痛大鼠蓝斑中GRK5、β-抑制蛋白2和PKCα蛋白的表达来缓解疼痛]
[Bone-edge electroacupuncture relieves pain by regulating expression of GRK5, β-arrestin 2 and PKCα proteins in locus coeruleus in bone cancer pain rats with morphine tolerance].
作者信息
Du Jun Ying, Chen Feng, Jiang Bin, Fu Tao Fang, Fang Jian Qiao, Liang Yi
机构信息
The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou 310053, China.
The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou 310053; The First Affiliated Hospital of Jiaxing College, Jiaxing 314001, Zhejiang Province.
出版信息
Zhen Ci Yan Jiu. 2020 Feb 25;45(2):87-92. doi: 10.13702/j.1000-0607.1900036.
OBJECTIVE
To observe the effect of bone-edge electroacupuncture (EA) intervention on mechanical pain threshold (PT) and expression of G protein-coupled receptor kinase (GRK5), β-arrestin 2, total and phosphorylated PKC alpha (p-PKCα) proteins in the locus coeruleus (LC) of rats with bone cancer pain induced morphine tolerance, so as to reveal its partial central mechanisms underlying pain relief.
METHODS
Forty SD rats were randomly divided into 5 groups, namely sham bone cancer, bone cancer pain, morphine tolerance, bone-edge EA, and sham EA (＝ 8 rats in each group). The bone cancer with morphine tolerance model was established by intramedullary injection of MRMT-1 cells into the tibial cavity, and then intraperitoneal injection of morphine hydrochloride injection. After successful establishment of morphine tolerance model, the bone-edge EA (2 Hz/100 Hz，0.5－1.5 mA) was applied to bilateral "Zusanli" (ST36) and "Kunlun" (BL60) for 30 min, once a day for 7 days, after inserting the needle-tip to the tibial bone surface. The ipsilateral mechanical paw withdrawal thresholds (PWTs) were detected dynamically. The expression levels of GRK5, β-arrestin 2, PKCα and p-PKCα in the LC area were measured by Western blot.
RESULTS
The PWTs of bone cancer pain rats were decreased on day 10 after inoculation of cancer cells (<0.01). After i．p. of morphine for 11 days, no analgesic effect and pain tolerance appeared (>0.05). The PWTs were significantly increased in the bone-edge EA intervention group (<0.01), not in the sham EA group (>0.05). In comparison with the sham bone cancer group, the expression of GRK5 protein in morphine tolerance group was significantly decreased (<0.01); compared with morphine tolerance group, the expression of GRK5 protein in bone-edge EA group was increased(<0.01). In comparison with the sham bone cancer group, the expression of β-arrestin 2 and p-PKCα in bone cancer group significantly increased (<0.01). After the intervention, the increased β-arrestin 2 and p-PKCα expressions were reversed in the bone-edge EA group (<0.01); compared with morphine tolerance group and sham EA group, the expression of PKCα protein was decreased(<0.01).
CONCLUSION
Bone-edge EA can effectively relieve morphine tolerance in bone cancer pain rats, which may be related to its functions in up-regulating GRK5 protein and down-regulating β-arrestin 2, PKCα and p-PKCα proteins in LC. .
目的
观察骨边缘电针干预对吗啡耐受的骨癌痛大鼠机械痛阈（PT）及蓝斑（LC）中G蛋白偶联受体激酶（GRK5）、β-抑制蛋白2、蛋白激酶Cα（PKCα）总量及磷酸化PKCα（p-PKCα）蛋白表达的影响，以揭示其缓解疼痛的部分中枢机制。
方法
40只SD大鼠随机分为5组，即假骨癌组、骨癌痛组、吗啡耐受组、骨边缘电针组和假电针组（每组8只）。采用髓腔内注射MRMT-1细胞至胫骨骨髓腔，随后腹腔注射盐酸吗啡注射液建立吗啡耐受的骨癌痛模型。成功建立吗啡耐受模型后，将针尖端刺入胫骨骨表面，对双侧“足三里”（ST36）和“昆仑”（BL60）施加骨边缘电针（2Hz/100Hz，0.5～1.5mA），每次30分钟，每天1次，共7天。动态检测患侧机械缩爪阈值（PWTs）。采用蛋白质免疫印迹法检测LC区GRK5、β-抑制蛋白2、PKCα和p-PKCα的表达水平。
结果
接种癌细胞后第10天，骨癌痛大鼠的PWTs降低（<0.01）。腹腔注射吗啡11天后，未出现镇痛作用和痛耐受（>0.05）。骨边缘电针干预组的PWTs显著升高（<0.01），假电针组则无明显变化（>0.05）。与假骨癌组相比，吗啡耐受组GRK5蛋白表达显著降低（<0.01）；与吗啡耐受组相比，骨边缘电针组GRK5蛋白表达升高（<0.01）。与假骨癌组相比，骨癌组β-抑制蛋白2和p-PKCα表达显著增加（<0.01）。干预后，骨边缘电针组β-抑制蛋白2和p-PKCα升高的表达被逆转（<0.01）；与吗啡耐受组和假电针组相比，PKCα蛋白表达降低（<0.01）。
结论
骨边缘电针可有效缓解骨癌痛大鼠的吗啡耐受，这可能与其上调LC中GRK5蛋白以及下调β-抑制蛋白2、PKCα和p-PKCα蛋白的作用有关。
Zotero 插件