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Chang X, Zhang H, Chen S. Neural circuits regulating visceral pain. Commun Biol 2024; 7:457. [PMID: 38615103 PMCID: PMC11016080 DOI: 10.1038/s42003-024-06148-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 04/05/2024] [Indexed: 04/15/2024] Open
Abstract
Visceral hypersensitivity, a common clinical manifestation of irritable bowel syndrome, may contribute to the development of chronic visceral pain, which is a major challenge for both patients and health providers. Neural circuits in the brain encode, store, and transfer pain information across brain regions. In this review, we focus on the anterior cingulate cortex and paraventricular nucleus of the hypothalamus to highlight the progress in identifying the neural circuits involved in visceral pain. We also discuss several neural circuit mechanisms and emphasize the importance of cross-species, multiangle approaches and the identification of specific neurons in determining the neural circuits that control visceral pain.
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Affiliation(s)
- Xiaoli Chang
- College of Acupuncture and Massage, Shandong University of Traditional Chinese Medicine, Jinan, 250355, China.
- Research Institute of Acupuncture and Moxibustion, Shandong University of Traditional Chinese Medicine, Jinan, 250355, China.
| | - Haiyan Zhang
- Research Institute of Acupuncture and Moxibustion, Shandong University of Traditional Chinese Medicine, Jinan, 250355, China
| | - Shaozong Chen
- Research Institute of Acupuncture and Moxibustion, Shandong University of Traditional Chinese Medicine, Jinan, 250355, China.
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2
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Zheng W, Huang X, Wang J, Gao F, Chai Z, Zeng J, Li S, Yu C. The chronification mechanism of orofacial inflammatory pain: Facilitation by GPER1 and microglia in the rostral ventral medulla. Front Mol Neurosci 2023; 15:1078309. [PMID: 36683848 PMCID: PMC9853019 DOI: 10.3389/fnmol.2022.1078309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 12/12/2022] [Indexed: 01/08/2023] Open
Abstract
Background Chronic orofacial pain is a common and incompletely defined clinical condition. The role of G protein-coupled estrogen receptor 1 (GPER1) as a new estrogen receptor in trunk and visceral pain regulation is well known. Here, we researched the role of GPER1 in the rostral ventral medulla (RVM) during chronic orofacial pain. Methods and Results A pain model was established where rats were injected in the temporomandibular joint with complete Freund's adjuvant (CFA) to simulate chronic orofacial pain. Following this a behavioral test was performed to establish pain threshold and results showed that the rats injected with CFA had abnormal pain in the orofacial regions. Additional Immunostaining and blot analysis indicated that microglia were activated in the RVM and GPER1 and c-Fos were significantly upregulated in the rats. Conversely, when the rats were injected with G15 (a GPER1 inhibitor) the abnormal pain the CFA rats were experiencing was alleviated and microglia activation was prevented. In addition, we found that G15 downregulated the expression of phospholipase C (PLC) and protein kinase C (PKC), inhibited the expression of GluA1, restores aberrant synaptic plasticity and reduces the overexpression of the synapse-associated proteins PSD-95 and syb-2 in the RVM of CFA rats. Conclusion The findings indicate that GPER1 mediates chronic orofacial pain through modulation of the PLC-PKC signal pathway, sensitization of the RVM region and enhancement of neural plasticity. These results of this study therefore suggest that GPER1 may serve as a potential therapeutic target for chronic orofacial pain.
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Affiliation(s)
- Wenwen Zheng
- The Affiliated Hospital of Stomatology, Chongqing Medical University, Chongqing, China
| | - Xilu Huang
- The Affiliated Hospital of Stomatology, Chongqing Medical University, Chongqing, China
| | - Jing Wang
- The Affiliated Hospital of Stomatology, Chongqing Medical University, Chongqing, China
| | - Feng Gao
- The Sixth People’s Hospital of Chongqing, Anesthesiology, Chongqing, China
| | - Zhaowu Chai
- The Affiliated Hospital of Stomatology, Chongqing Medical University, Chongqing, China
| | - Jie Zeng
- The Affiliated Hospital of Stomatology, Chongqing Medical University, Chongqing, China
| | - Sisi Li
- The Affiliated Hospital of Stomatology, Chongqing Medical University, Chongqing, China
| | - Cong Yu
- The Affiliated Hospital of Stomatology, Chongqing Medical University, Chongqing, China,*Correspondence: Cong Yu, ✉
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3
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Jiao Y, Gao P, Dong L, Ding X, Meng Y, Qian J, Gao T, Wang R, Jiang T, Zhang Y, Kong D, Wu Y, Chen S, Xu S, Tang D, Luo P, Wu M, Meng L, Wen D, Wu C, Zhang G, Shi X, Yu W, Rong W. Molecular identification of bulbospinal ON neurons by GPER, which drives pain and morphine tolerance. J Clin Invest 2023; 133:e154588. [PMID: 36346677 PMCID: PMC9797334 DOI: 10.1172/jci154588] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 11/02/2022] [Indexed: 11/09/2022] Open
Abstract
The rostral ventromedial medulla (RVM) exerts bidirectional descending modulation of pain attributable to the activity of electrophysiologically identified pronociceptive ON and antinociceptive OFF neurons. Here, we report that GABAergic ON neurons specifically express G protein-coupled estrogen receptor (GPER). GPER+ neurons exhibited characteristic ON-like responses upon peripheral nociceptive stimulation. Optogenetic activation of GPER+ neurons facilitated, but their ablation abrogated, pain. Furthermore, activation of GPER caused depolarization of ON cells, potentiated pain, and ameliorated morphine analgesia through desensitizing μ-type opioid receptor-mediated (MOR-mediated) activation of potassium currents. In contrast, genetic ablation or pharmacological blockade of GPER attenuated pain, enhanced morphine analgesia, and delayed the development of morphine tolerance in diverse preclinical pain models. Our data strongly indicate that GPER is a marker for GABAergic ON cells and illuminate the mechanisms underlying hormonal regulation of pain and analgesia, thus highlighting GPER as a promising target for the treatment of pain and opioid tolerance.
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Affiliation(s)
- Yingfu Jiao
- Department of Anatomy and Physiology and
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Po Gao
- Department of Anatomy and Physiology and
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Li Dong
- Department of Anatomy and Physiology and
| | | | - Youqiang Meng
- Department of Anatomy and Physiology and
- Department of Neurosurgery, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Chongming Branch, Shanghai University of Medicine and Health Sciences Affiliated Chongming Hospital, Shanghai, China
| | | | - Ting Gao
- Department of Anatomy and Physiology and
| | - Ruoxi Wang
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Tao Jiang
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yunchun Zhang
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Dexu Kong
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yi Wu
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Sihan Chen
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Saihong Xu
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Dan Tang
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ping Luo
- Department of Anatomy and Physiology and
| | - Meimei Wu
- Department of Anatomy and Physiology and
| | - Li Meng
- Department of Anatomy and Physiology and
| | - Daxiang Wen
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Changhao Wu
- School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
| | | | - Xueyin Shi
- Department of Anesthesiology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Weifeng Yu
- Department of Anesthesiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Weifang Rong
- Department of Anatomy and Physiology and
- Department of Anesthesiology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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4
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Xie Z, Feng J, Cai T, McCarthy R, Eschbach Ii MD, Wang Y, Zhao Y, Yi Z, Zang K, Yuan Y, Hu X, Li F, Liu Q, Das A, England SK, Hu H. Estrogen metabolites increase nociceptor hyperactivity in a mouse model of uterine pain. JCI Insight 2022; 7:149107. [PMID: 35420999 PMCID: PMC9220826 DOI: 10.1172/jci.insight.149107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 04/12/2022] [Indexed: 11/17/2022] Open
Abstract
Pain emanating from the female reproductive tract is notoriously difficult to be treated and the prevalence of transient pelvic pain has been placed as high as 70-80% in women surveyed. Although sex hormones, especially estrogen, are thought to underlie enhanced pain perception in females, the underlying molecular and cellular mechanisms are not completely understood. Here we show that the pain-initiating TRPA1 channel is required for pain-related behaviors in a mouse model of estrogen-induced uterine pain in ovariectomized female mice. Surprisingly, 2- and 4-hydroxylated estrogen metabolites (HEMs) in the estrogen hydroxylation pathway, but not estrone, estradiol and 16-HEMs, directly increase nociceptor hyperactivity through TRPA1 and TRPV1 channels, and picomolar concentrations of 2- and 4-hydroxylation estrone (OHE1) can sensitize TRPA1 channel function. Moreover, both TRPA1 and TRPV1 are expressed in uterine-innervating primary nociceptors and their expressions are increased in the estrogen-induced uterine pain model. Importantly, pretreatment of 2- or 4-OHE1 recapitulates estrogen-induced uterine pain-like behaviors and intraplantar injections of 2- and 4-OHE1 directly produce a TRPA1-dependent mechanical hypersensitivity. Our findings demonstrate that TRPA1 is critically involved in estrogen-induced uterine pain-like behaviors, which may provide a potential drug target for treating female reproductive tract pain.
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Affiliation(s)
- Zili Xie
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Jing Feng
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Tao Cai
- The First Affiliated Hospital of Chongqing Medical University, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ronald McCarthy
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, United States of America
| | - Mark D Eschbach Ii
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, United States of America
| | - Yuhui Wang
- Department of Anesthesiology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yonghui Zhao
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Zhihua Yi
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Kaikai Zang
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Yi Yuan
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Xueming Hu
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Fengxian Li
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Qin Liu
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Aditi Das
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, United States of America
| | - Sarah K England
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, United States of America
| | - Hongzhen Hu
- Washington University School of Medicine, St. Louis, United States of America
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Xu JJ, Gao P, Wu Y, Yin SQ, Zhu L, Xu SH, Tang D, Cheung CW, Jiao YF, Yu WF, Li YH, Yang LQ. G protein-coupled estrogen receptor in the rostral ventromedial medulla contributes to the chronification of postoperative pain. CNS Neurosci Ther 2021; 27:1313-1326. [PMID: 34255932 PMCID: PMC8504531 DOI: 10.1111/cns.13704] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 06/19/2021] [Accepted: 06/29/2021] [Indexed: 12/18/2022] Open
Abstract
Aims Chronification of postoperative pain is a common clinical phenomenon following surgical operation, and it perplexes a great number of patients. Estrogen and its membrane receptor (G protein‐coupled estrogen receptor, GPER) play a crucial role in pain regulation. Here, we explored the role of GPER in the rostral ventromedial medulla (RVM) during chronic postoperative pain and search for the possible mechanism. Methods and Results Postoperative pain was induced in mice or rats via a plantar incision surgery. Behavioral tests were conducted to detect both thermal and mechanical pain, showing a small part (16.2%) of mice developed into pain persisting state with consistent low pain threshold on 14 days after incision surgery compared with the pain recovery mice. Immunofluorescent staining assay revealed that the GPER‐positive neurons in the RVM were significantly activated in pain persisting rats. In addition, RT‐PCR and immunoblot analyses showed that the levels of GPER and phosphorylated μ‐type opioid receptor (p‐MOR) in the RVM of pain persisting mice were apparently increased on 14 days after incision surgery. Furthermore, chemogenetic activation of GPER‐positive neurons in the RVM of Gper‐Cre mice could reverse the pain threshold of pain recovery mice. Conversely, chemogenetic inhibition of GPER‐positive neurons in the RVM could prevent mice from being in the pain persistent state. Conclusion Our findings demonstrated that the GPER in the RVM was responsible for the chronification of postoperative pain and the downstream pathway might be involved in MOR phosphorylation.
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Affiliation(s)
- Jia-Jia Xu
- Department of Anesthesiology, The First Affiliated Hospital of Anhui Medical University, Hefei, China.,Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Po Gao
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Ying Wu
- Department of Anesthesiology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Su-Qing Yin
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Ling Zhu
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Sai-Hong Xu
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Dan Tang
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Chi-Wai Cheung
- Department of Anesthesiology, The University of Hong Kong, Hong Kong, China
| | - Ying-Fu Jiao
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Wei-Feng Yu
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Yuan-Hai Li
- Department of Anesthesiology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Li-Qun Yang
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
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Abstract
This paper is the fortieth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2017 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, CUNY, 65-30 Kissena Blvd., Flushing, NY, 11367, United States.
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Sun LH, Zhang WX, Xu Q, Wu H, Jiao CC, Chen XZ. Estrogen modulation of visceral pain. J Zhejiang Univ Sci B 2020; 20:628-636. [PMID: 31273960 DOI: 10.1631/jzus.b1800582] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
It is commonly accepted that females and males differ in their experience of pain. Gender differences have been found in the prevalence and severity of pain in both clinical and animal studies. Sex-related hormones are found to be involved in pain transmission and have critical effects on visceral pain sensitivity. Studies have pointed out the idea that serum estrogen is closely related to visceral nociceptive sensitivity. This review aims to summarize the literature relating to the role of estrogen in modulating visceral pain with emphasis on deciphering the potential central and peripheral mechanisms.
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Affiliation(s)
- Li-Hong Sun
- Department of Anesthesiology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China
| | - Wen-Xin Zhang
- Department of Anesthesiology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China
| | - Qi Xu
- Department of Anesthesiology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China
| | - Hui Wu
- Department of Anesthesiology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China
| | - Cui-Cui Jiao
- Department of Anesthesiology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China
| | - Xin-Zhong Chen
- Department of Anesthesiology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China
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Brocca ME, Garcia-Segura LM. Non-reproductive Functions of Aromatase in the Central Nervous System Under Physiological and Pathological Conditions. Cell Mol Neurobiol 2018; 39:473-481. [PMID: 30084008 DOI: 10.1007/s10571-018-0607-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 07/25/2018] [Indexed: 02/07/2023]
Abstract
The modulation of brain function and behavior by steroid hormones was classically associated with their secretion by peripheral endocrine glands. The discovery that the brain expresses the enzyme aromatase, which produces estradiol from testosterone, expanded this traditional concept. One of the best-studied roles of brain estradiol synthesis is the control of reproductive behavior. In addition, there is increasing evidence that estradiol from neural origin is also involved in a variety of non-reproductive functions. These include the regulation of neurogenesis, neuronal development, synaptic transmission, and plasticity in brain regions not directly related with the control of reproduction. Central aromatase is also involved in the modulation of cognition, mood, and non-reproductive behaviors. Furthermore, under pathological conditions aromatase is upregulated in the central nervous system. This upregulation represents a neuroprotective and likely also a reparative response by increasing local estradiol levels in order to maintain the homeostasis of the neural tissue. In this paper, we review the non-reproductive functions of neural aromatase and neural-derived estradiol under physiological and pathological conditions. We also consider the existence of sex differences in the role of the enzyme in both contexts.
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Affiliation(s)
- Maria Elvira Brocca
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain.
| | - Luis Miguel Garcia-Segura
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- Centro de Investigación Biomédica en Red Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
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Gao P, Ding XW, Dong L, Luo P, Zhang GH, Rong WF. Expression of aromatase in the rostral ventromedial medulla and its role in the regulation of visceral pain. CNS Neurosci Ther 2017; 23:980-989. [PMID: 29047208 DOI: 10.1111/cns.12769] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 09/22/2017] [Accepted: 09/25/2017] [Indexed: 12/30/2022] Open
Abstract
AIMS Estrogens are known to exert a wide spectrum of actions on brain functions including modulation of pain. Besides the circulating estrogens produced mainly by the ovaries, many brain regions are also capable of de novo synthesizing estrogens, which may exert important modulatory effects on neuronal functions. This study was aimed to test the hypothesis that aromatase, the enzyme that catalyzes the conversion of testosterone to estradiols, may be distributed in the rostral ventromedial medulla (RVM), where it may impact on visceral pain. METHODS AND RESULTS Adult female rats were treated with cyclophosphamide (CPM, 50 mg/kg, ip, once every 3 days) or saline. At approximately day 10 following the 3rd injection, CPM-treated rats exhibited colorectal hyperalgesia as they showed significantly greater abdominal withdrawal responses (AWR) to graded colorectal distension (CRD, 0-100 mm Hg) than the saline group. Immunofluorescent staining and Western blot assay revealed that CPM-induced colorectal hyperalgesia was associated with significantly increased expression of aromatase and phosphorylated μ-type opioid receptor (pMOR) and decreased expression of total MOR in the RVM. Intracisternal application of aromatase inhibitors, fadrozole, and letrozole reversed CPM-induced colorectal hyperalgesia and restored pMOR and MOR expression in the RVM. CONCLUSIONS Our observations confirmed the expression of aromatase in the RVM, a pivotal brain region in descending modulation of pain and opioid analgesia. The results support the hypothesis that locally produced estrogens in the RVM may be involved in the maintenance of chronic visceral hyperalgesia and the downstream signaling may involve phosphorylation of MOR.
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Affiliation(s)
- Po Gao
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xiao-Wei Ding
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Li Dong
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Ping Luo
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Guo-Hua Zhang
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Wei-Fang Rong
- Hongqiao International Institute of Medical Research, Tongren Hospital and Department of Physiology, Faculty of Basic Medical Sciences, Shanghai Jiaotong University School of Medicine, Shanghai, China.,Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan, China
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