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Wang S, Du J, Xi D, Shao F, Qiu M, Shao X, Liang Y, Liu B, Jin X, Fang J, Fang J. Role of GABAAR in the Transition From Acute to Chronic Pain and the Analgesic Effect of Electroacupuncture on Hyperalgesic Priming Model Rats. Front Neurosci 2021; 15:691455. [PMID: 34220444 PMCID: PMC8248374 DOI: 10.3389/fnins.2021.691455] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 05/25/2021] [Indexed: 11/18/2022] Open
Abstract
Chronic pain is a costly health problem that impairs health-related quality of life when not effectively treated. Regulating the transition from acute to chronic pain is a new therapeutic strategy for chronic pain that presents a major clinical challenge. The underlying mechanisms of pain transition are not entirely understood, and strategies for preventing this transition are lacking. Here, a hyperalgesic priming model was used to study the potential mechanism by which γ-aminobutyric acid receptor type A (GABAAR) in the dorsal root ganglion (DRG) contributes to pain transition. Furthermore, electroacupuncture (EA), a modern method of acupuncture, was administered to regulate pain transition, and the mechanism underlying EA’s regulatory effect was investigated. Hyperalgesic priming was induced by intraplanar injection of carrageenan (Car)/prostaglandin E2 (PGE2). The decrease in mechanical withdrawal threshold (MWT) induced by PGE2 returned to baseline 4 h after injection in NS + PGE2 group, and still persisted 24 h after injection in Car + PGE2 group. Lower expression of GABAAR in the lumbar DRG was observed in the model rats. Furthermore, activating or blocking GABAAR could reversed the long-lasting hyperalgesia induced by Car/PGE2 injection or produced a persistent hyperalgesia. In addition, GABAAR may be involved in Protein Kinase C epsilon (PKCε) activation in the DRG, a mark molecular of pain transition. EA considerably increased the mechanical pain thresholds of hyperalgesic priming model mammals in both the acute and chronic phases. Furthermore, EA upregulated the expression of GABAAR and inhibited the activation of PKCε in the DRG. In addition, peripheral administration of picrotoxin blocked the analgesic effect of EA on the model rats and abolished the regulatory effect of EA on PKCε activation. These findings suggested that GABAAR plays a key role in both the transition from acute to chronic pain and the analgesic effect of EA on hyperalgesic priming.
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Affiliation(s)
- Sisi Wang
- Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Junying Du
- Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Danning Xi
- Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Fangbing Shao
- Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Mengting Qiu
- Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Xiaomei Shao
- Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yi Liang
- Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Boyi Liu
- Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Xiaomin Jin
- Department of Anatomy, Cell Biology and Physiology, Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Jianqiao Fang
- Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Junfan Fang
- Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
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Wilke BU, Kummer KK, Leitner MG, Kress M. Chloride - The Underrated Ion in Nociceptors. Front Neurosci 2020; 14:287. [PMID: 32322187 PMCID: PMC7158864 DOI: 10.3389/fnins.2020.00287] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Accepted: 03/12/2020] [Indexed: 01/06/2023] Open
Abstract
In contrast to pain processing neurons in the spinal cord, where the importance of chloride conductances is already well established, chloride homeostasis in primary afferent neurons has received less attention. Sensory neurons maintain high intracellular chloride concentrations through balanced activity of Na+-K+-2Cl– cotransporter 1 (NKCC1) and K+-Cl– cotransporter 2 (KCC2). Whereas in other cell types activation of chloride conductances causes hyperpolarization, activation of the same conductances in primary afferent neurons may lead to inhibitory or excitatory depolarization depending on the actual chloride reversal potential and the total amount of chloride efflux during channel or transporter activation. Dorsal root ganglion (DRG) neurons express a multitude of chloride channel types belonging to different channel families, such as ligand-gated, ionotropic γ-aminobutyric acid (GABA) or glycine receptors, Ca2+-activated chloride channels of the anoctamin/TMEM16, bestrophin or tweety-homolog family, CLC chloride channels and transporters, cystic fibrosis transmembrane conductance regulator (CFTR) as well as volume-regulated anion channels (VRACs). Specific chloride conductances are involved in signal transduction and amplification at the peripheral nerve terminal, contribute to excitability and action potential generation of sensory neurons, or crucially shape synaptic transmission in the spinal dorsal horn. In addition, chloride channels can be modified by a plethora of inflammatory mediators affecting them directly, via protein-protein interaction, or through signaling cascades. Since chloride channels as well as mediators that modulate chloride fluxes are regulated in pain disorders and contribute to nociceptor excitation and sensitization it is timely and important to emphasize their critical role in nociceptive primary afferents in this review.
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Affiliation(s)
- Bettina U Wilke
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - Kai K Kummer
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - Michael G Leitner
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - Michaela Kress
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
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Tan CY, Wang YP, Han YY, Lu BH, Ji W, Zhu LC, Wang Y, Shi WY, Shan LY, Zhang L, Ma KT, Li L, Si JQ. Expression and effect of sodium-potassium-chloride cotransporter on dorsal root ganglion neurons in a rat model of chronic constriction injury. Neural Regen Res 2020; 15:912-921. [PMID: 31719257 PMCID: PMC6990784 DOI: 10.4103/1673-5374.268904] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Sodium-potassium-chloride cotransporter 1 (NKCC1) and potassium-chloride cotransporter 2 (KCC2) are associated with the transmission of peripheral pain. We investigated whether the increase of NKCC1 and KCC2 is associated with peripheral pain transmission in dorsal root ganglion neurons. To this aim, rats with persistent hyperalgesia were randomly divided into four groups. Rats in the control group received no treatment, and the rat sciatic nerve was only exposed in the sham group. Rats in the chronic constriction injury group were established into chronic constriction injury models by ligating sciatic nerve and rats were given bumetanide, an inhibitor of NKCC1, based on chronic constriction injury modeling in the chronic constriction injury + bumetanide group. In the experiment measuring thermal withdrawal latency, bumetanide (15 mg/kg) was intravenously administered. In the patch clamp experiment, bumetanide (10 µg/µL) and acutely isolated dorsal root ganglion neurons (on day 14) were incubated for 1 hour, or bumetanide (5 µg/µL) was intrathecally injected. The Hargreaves test was conducted to detect changes in thermal hyperalgesia in rats. We found that the thermal withdrawal latency of rats was significantly decreased on days 7, 14, and 21 after model establishment. After intravenous injection of bumetanide, the reduction in thermal retraction latency caused by model establishment was significantly inhibited. Immunohistochemistry and western blot assay results revealed that the immune response and protein expression of NKCC1 in dorsal root ganglion neurons of the chronic constriction injury group increased significantly on days 7, 14, and 21 after model establishment. No immune response or protein expression of KCC2 was observed in dorsal root ganglion neurons before and after model establishment. The Cl– (chloride ion) fluorescent probe technique was used to evaluate the change of Cl– concentration in dorsal root ganglion neurons of chronic constriction injury model rats. We found that the relative optical density of N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide (a Cl– fluorescent probe whose fluorescence intensity decreases as Cl– concentration increases) in the dorsal root ganglion neurons of the chronic constriction injury group was significantly decreased on days 7 and 14 after model establishment. The whole-cell patch clamp technique revealed that the resting potential and action potential frequency of dorsal root ganglion neurons increased, and the threshold and rheobase of action potentials decreased in the chronic constriction injury group on day 14 after model establishment. After bumetanide administration, the above indicators were significantly suppressed. These results confirm that CCI can induce abnormal overexpression of NKCC1, thereby increasing the Cl– concentration in dorsal root ganglion neurons; this then enhances the excitability of dorsal root ganglion neurons and ultimately promotes hyperalgesia and allodynia. In addition, bumetanide can achieve analgesic effects. All experiments were approved by the Institutional Ethics Review Board at the First Affiliated Hospital, College of Medicine, Shihezi University, China on February 22, 2017 (approval No. A2017-169-01).
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Affiliation(s)
- Chao-Yang Tan
- Department of Physiology, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region; Department of Physiology, Medical College of Jiaxing University, Jiaxing, Zhejiang Province; Department of Health, Karamay Army Division, Chinese People's Liberation Army, Karamay, Xinjiang Uygur Autonomous Region, China
| | - Yan-Ping Wang
- Department of Physiology; Department of Nursing, Medical College of Jiaxing University, Jiaxing, Zhejiang Province, China
| | - Yuan-Yuan Han
- Department of Physiology, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region; Department of Clinical Medicine, Karamay College of Xinjiang Medical University, Karamay, Xinjiang Uygur Autonomous Region, China
| | - Bi-Han Lu
- Department of Physiology, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region, China
| | - Wei Ji
- Department of Physiology, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region, China
| | - Li-Cang Zhu
- Department of Neurosurgery, First Affiliated Hospital, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region, China
| | - Yang Wang
- Department of Physiology, College of Medicine; The key Laboratory of Xinjiang Endemic and Ethnic Diseases, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region, China
| | - Wen-Yan Shi
- Department of Physiology, College of Medicine; The key Laboratory of Xinjiang Endemic and Ethnic Diseases, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region, China
| | - Li-Ya Shan
- Department of Physiology, College of Medicine; The key Laboratory of Xinjiang Endemic and Ethnic Diseases, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region, China
| | - Liang Zhang
- Department of Physiology, College of Medicine; The key Laboratory of Xinjiang Endemic and Ethnic Diseases, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region, China
| | - Ke-Tao Ma
- Department of Physiology, College of Medicine; The key Laboratory of Xinjiang Endemic and Ethnic Diseases, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region, China
| | - Li Li
- Department of Physiology, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region; Department of Physiology, Medical College of Jiaxing University, Jiaxing, Zhejiang Province; The key Laboratory of Xinjiang Endemic and Ethnic Diseases, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region, China
| | - Jun-Qiang Si
- Department of Physiology; The key Laboratory of Xinjiang Endemic and Ethnic Diseases, College of Medicine, Shihezi University, Shihezi, Xinjiang Uygur Autonomous Region; Department of Physiology, School of Basic Medical Sciences, Wuhan University; Department of Physiology, School of Basic Medical Sciences, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
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Qiao LN, Yang YS, Liu JL, Zhu J, Tan LH, Shi YN, Zhu B, Rong PJ. Contribution of GABAergic modulation in DRGs to electroacupuncture analgesia in incisional neck pain rats. J Pain Res 2019; 12:405-416. [PMID: 30705606 PMCID: PMC6342219 DOI: 10.2147/jpr.s180165] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Purpose Acupuncture therapy is effective for relieving postoperative pain. Our previous study showed that electroacupuncture (EA) at Futu (LI18) and Hegu (LI4)–Neiguan (PC6) could alleviate incisional neck pain, which was related with its effect in upregulating γ-aminobutyric acid (GABA) expression in cervical (C3–6) dorsal root ganglions (DRGs); but whether its receptor subsets GABAAα2R and GABABR1 in C3–6 DRGs are involved in EA analgesia or not, it remains unknown. Materials and methods Seventy-five male Sprague Dawley rats were randomized to normal control, model, LI18, LI4–PC6, and Zusanli (ST36)–Yanglingquan (GB34) groups. The incisional neck pain model was established by making a longitudinal incision along the midline of the rats’ neck, followed by repeated mechanical stimulation. EA was applied to bilateral LI18, LI4–PC6, or ST36–GB34 for 30 minutes at 4, 24, and 48 hours after operation. The thermal pain threshold of the neck was detected by a tail-flick unit, and the C3–6 DRGs were removed for assaying the immunoactivity of substance P (SP), GABAAα2R, glial fibrillary acidic protein (GFAP; a marker of satellite glial cells [SGCs]), and GABABR1 and the expression of GABAAα2R and GABABR1 mRNA and proteins using immunofluorescence, real-time PCR, and Western blotting, respectively. Results The cervical thermal pain threshold was significantly lower in the model group than the normal group (P<0.001), indicating hyperalgesia after neck incision, and was considerably increased in both EA-LI18 and LI4–PC6 groups (P<0.001), but not in ST36–GB34 group compared with model group (P>0.05). Immunofluorescence staining showed that GABAAα2 R expressed on SP+ neurons, and GABABR1 on SGCs. EA of LI18 and LI4–PC6 markedly suppressed the modeling-induced upregulation of the immunoactivity of SP (P<0.001 and P<0.01, respectively) and GFAP (P<0.01 and P<0.001, respectively) and significantly reversed neck incision–induced downregulation of the expression of GABAAα2R and GABABR1 mRNAs and proteins (P<0.05). Conclusion EA of LI18 and LI4–PC6 has an analgesic effect in incisional neck pain rats, which is related to its effects in upregulating GABAergic inhibitory modulation on nociceptive peptidergic neurons and SGCs in cervical DRGs.
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Affiliation(s)
- Li Na Qiao
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China.,Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China, ;
| | - Yong Sheng Yang
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China, ;
| | - Jun Ling Liu
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China, ;
| | - Jiang Zhu
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Lian Hong Tan
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China, ;
| | - Yi Nan Shi
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China, ;
| | - Bing Zhu
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China, ;
| | - Pei Jing Rong
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China, ;
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Zhang M, Gao CX, Wang YP, Ma KT, Li L, Yin JW, Dai ZG, Wang S, Si JQ. The association between the expression of PAR2 and TMEM16A and neuropathic pain. Mol Med Rep 2017; 17:3744-3750. [PMID: 29257338 PMCID: PMC5802179 DOI: 10.3892/mmr.2017.8295] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 12/08/2017] [Indexed: 12/12/2022] Open
Abstract
Chronic constriction injury (CCI) of the sciatic nerve may induce dorsal root ganglion (DRG) neuronal hyperexcitability and behaviorally expressed hyperalgesia. CCI is a model of neuropathic pain. To investigate the association between the expression of protease activated receptor 2 (PAR2), TMEM16A and neuropathic pain, the expression of PAR2 and TMEM16A proteins in the DRG neurons of rats following CCI of the sciatic nerve was investigated. Following the creation of the CCI model, the thermal withdrawal latency (TWL) was examined by a hot plate test. An immunofluorescence assay and western blot assay were performed to determine the expression of PAR2 and TMEM16A proteins in the ipsilateral L4–6 DRG neurons. The concentration of inositol 1,4,5-triphosphate (IP3) in the L4–6 DRG was determined by ELISA. In the CCI-D7 (7 days after CCI) and CCI-D14 (14 days after CCI) treatment groups, the TWL of rats was significantly shorter than that in the sham operated group (P<0.01; n=12). The expression of PAR2 and TMEM16A proteins in the CCI-D7 and CCI-D14 groups were significantly upregulated compared with the sham operated group (P<0.05; n=12). Additionally, it was revealed that PAR2 and TMEM16A were co-expressed in DRG neurons. It was also observed that IP3 significantly increased in the CCI-D7 and CCI-D14 groups compared with the sham operation group (P<0.05; n=6) as PAR2 and TMEM16A also increased. These findings suggest that the upregulation of PAR2 and TMEM16A in DRG neurons, the co-expression of the two proteins and increasing IP3 are critical to the development of neuropathic pain.
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Affiliation(s)
- Meng Zhang
- Department of Anesthesiology, The First Affiliated Hospital of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Cun-Xiang Gao
- Department of Urology, The First Affiliated Hospital of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Yan-Ping Wang
- Houbo College, Xinjiang Medical University, Karamay, Xinjiang 834000, P.R. China
| | - Ke-Tao Ma
- Electrophysiological Laboratory, Laboratory of Xinjiang Endemic and Ethnic Diseases, Medical College, Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Li Li
- Electrophysiological Laboratory, Laboratory of Xinjiang Endemic and Ethnic Diseases, Medical College, Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Jiang-Wen Yin
- Department of Anesthesiology, The First Affiliated Hospital of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Zhi-Gang Dai
- Department of Anesthesiology, The First Affiliated Hospital of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Sheng Wang
- Department of Anesthesiology, The First Affiliated Hospital of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Jun-Qiang Si
- Electrophysiological Laboratory, Laboratory of Xinjiang Endemic and Ethnic Diseases, Medical College, Shihezi University, Shihezi, Xinjiang 832002, P.R. China
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Wang LJ, Wang Y, Chen MJ, Tian ZP, Lu BH, Mao KT, Zhang L, Zhao L, Shan LY, Li L, Si JQ. Effects of niflumic acid on γ-aminobutyric acid-induced currents in isolated dorsal root ganglion neurons of neuropathic pain rats. Exp Ther Med 2017; 14:1373-1380. [PMID: 28810599 PMCID: PMC5526125 DOI: 10.3892/etm.2017.4666] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Accepted: 04/10/2017] [Indexed: 12/15/2022] Open
Abstract
Niflumic acid (NFA) is a type of non-steroidal anti-inflammatory drug. Neuropathic pain is caused by a decrease in presynaptic inhibition mediated by γ-aminobutyric acid (GABA). In the present study, a whole-cell patch-clamp technique and intracellular recording were used to assess the effect of NFA on GABA-induced inward current in dorsal root ganglion (DRG) neurons of a chronic constriction injury (CCI) model. It was observed that 1–1,000 µmol/l GABA induced a concentration-dependent inward current in DRG neurons. Compared with pseudo-operated rats, the thermal withdrawal latency (TWL) of CCI rats significantly decreased (P<0.01); however, the TWLs of each NFA group (50 and 300 µmol/l) were significantly longer than that of the CCI group (P<0.01). In the CCI group, the response evoked by GABA (10−6-10−3 mol/l) was reduced in a concentration dependent manner compared with a normal control group (P<0.01), and the current amplitudes of CCI rats activated by the same concentrations of GABA (10−6-10−3 mol/l) were significantly decreased compared with the control group (P<0.05). The inward currents activated by 100 µmol/l GABA were suppressed by treatment with 1, 10 and 100 µmol/l NFA (5.32±3.51, 33.8±5.20, and 52.2±6.32%, respectively; P<0.05). The inverse potentials of GABA-induced currents were 9.87±1.32 and 9.64±1.24 mV with and without NFA, respectively (P<0.05). Pre-treatment with NFA exerted a strong inhibitory effect on the peak value of GABA-induced current, and the GABA-induced response was inhibited by the same concentrations of NFA (1, 10 and 100 µmol/l) in the control and CCI groups (P<0.05). The results suggest that NFA reduced the primary afferent depolarization (PAD) associated with neuropathic pain and mediated by the GABAA receptor. NFA may regulate neuropathic pain by inhibiting dorsal root reflexes, which are triggered PAD.
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Affiliation(s)
- Li-Jie Wang
- Department of Physiology, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China
| | - Yang Wang
- Department of Physiology, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China.,The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China.,Department of Physiology, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei 430071, P.R. China
| | - Meng-Jie Chen
- Department of Physiology, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China
| | - Zhen-Pu Tian
- Department of Physiology, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China
| | - Bi-Han Lu
- Department of Physiology, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China
| | - Ke-Tao Mao
- Department of Physiology, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China.,The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China
| | - Liang Zhang
- Department of Physiology, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China.,The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China
| | - Lei Zhao
- Department of Physiology, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China.,The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China
| | - Li-Ya Shan
- Department of Physiology, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China.,The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China
| | - Li Li
- Department of Physiology, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China.,The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China
| | - Jun-Qiang Si
- Department of Physiology, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China.,The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, Xinjiang 832002, P.R. China.,Department of Physiology, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei 430071, P.R. China.,Department of Physiology, Huazhong University of Science and Technology, Wuhan, Hubei 430070, P.R. China
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7
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Qiao LN, Liu JL, Tan LH, Yang HL, Zhai X, Yang YS. Effect of electroacupuncture on thermal pain threshold and expression of calcitonin-gene related peptide, substance P and γ-aminobutyric acid in the cervical dorsal root ganglion of rats with incisional neck pain. Acupunct Med 2017; 35:276-283. [PMID: 28600329 PMCID: PMC5561363 DOI: 10.1136/acupmed-2016-011177] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2017] [Indexed: 02/06/2023]
Abstract
Objective Acupuncture therapy effectively reduces post-surgical pain, but its mechanism of action remains unclear. The aim of this study was to investigate whether expression of γ-aminobutyric acid (GABA) and the neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) in the primary sensory neurons of cervical dorsal root ganglia (DRG) are involved in electroacupuncture (EA)-induced analgesia in a rat model of incisional neck pain. Methods The pain model was established by making a longitudinal midline neck incision in 60 rats. Another 15 rats underwent sham surgery (normal group). Post-incision, 15 rats remained untreated (model group) and 45 rats underwent EA (frequency 2/100 Hz, intensity 1 mA) at bilateral LI18, LI4-PC6 or ST36-GB34 (n=15 each) for 30 min at 4 hours, 24 hours, and 48 hours post-surgery, followed by thermal pain threshold (PT) measurement. 30 min later, the rats were euthanased and cervical (C3-6) DRGs removed for measurement of immunoreactivity and mRNA expression of SP/CGRP and the GABAergic neuronal marker glutamic acid decarboxylase 67 (GAD67). Results Thermal PT was significantly lower in the model group versus the normal group and increased in the LI18 and LI4-PC6 groups but not the ST36-GB34 group compared with the model group. Additionally, EA at LI18 and LI4-PC6 markedly suppressed neck incision-induced upregulation of mRNA/protein expression of SP/CGRP, and upregulated mRNA/protein expression of GAD67 in the DRGs of C3-6 segments. Conclusions EA at LI18/LI4-PC6 increases PT in rats with incisional neck pain, which is likely related to downregulation of pronociceptive mediators SP/CGRP and upregulation of the inhibitory transmitter GABA in the primary sensory neurons of cervical DRGs.
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Affiliation(s)
- Li-Na Qiao
- Department of Biochemistry and Molecular Biology, Institute of Acu-Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Jun-Ling Liu
- Department of Physiology, Institute of Acu-Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Lian-Hong Tan
- Department of Biochemistry and Molecular Biology, Institute of Acu-Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Hai-Long Yang
- Department of Biochemistry and Molecular Biology, Institute of Acu-Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.,Institute of Acupuncture and Massage, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Xu Zhai
- Department of Biochemistry and Molecular Biology, Institute of Acu-Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yong-Sheng Yang
- Department of Biochemistry and Molecular Biology, Institute of Acu-Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
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