1
|
Pentobarbital may protect against neurogenic inflammation after surgery via inhibition of substance P release from peripheral nerves of rats. Neurosci Lett 2022; 771:136467. [DOI: 10.1016/j.neulet.2022.136467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 12/28/2021] [Accepted: 01/15/2022] [Indexed: 11/23/2022]
|
2
|
Hamers A, Primus CP, Whitear C, Kumar NA, Masucci M, Montalvo Moreira SA, Rathod K, Chen J, Bubb K, Colas R, Khambata RS, Dalli J, Ahluwalia A. 20-HETE is a pivotal endogenous ligand for TRPV1-mediated neurogenic inflammation in the skin. Br J Pharmacol 2021; 179:1450-1469. [PMID: 34755897 DOI: 10.1111/bph.15726] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 10/11/2021] [Accepted: 10/26/2021] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Transient receptor potential cation channel subfamily V member 1 (TRPV1) is localised to sensory C-fibres and its opening leads to membrane depolarization, resulting in neuropeptide release and neurogenic inflammation. However, the identity of the endogenous activator of TRPV1 in this setting is unknown. The arachidonic acid (AA) metabolites 12-hydroperoxyeicosatetraenoyl acid (12-HpETE) and 20-hydroxyeicosatetraenoic acid (20-HETE) have emerged as potential endogenous activators of TRPV1 however, whether these lipids underlie TRPV1-mediated neurogenic inflammation remains unknown. EXPERIMENTAL APPROACH we analysed human cantharidin-induced blister samples and inflammatory responses in TRPV1 transgenic mice. KEY RESULTS In a human cantharidin-blister model the potent TRPV1 activators 20-HETE but not 12-HETE (stable metabolite of 12-HpETE) correlated with AA levels. Similarly, in mice levels of 20-HETE (but not 12-HETE) and AA were strongly positively correlated within the inflammatory milieu. Furthermore, LPS-induced oedema formation and neutrophil recruitment were substantially and significantly attenuated by pharmacological block or genetic deletion of TRPV1 channels, inhibition of 20-HETE formation or SP receptor neurokinin 1 (NK1 ) blockade. LPS treatment also increased cytochrome-P450 ώ-hydroxylase gene expression, the enzyme responsible for 20-HETE production. CONCLUSIONS AND IMPLICATIONS Taken together, our findings suggest that endogenously generated 20-HETE activates TRPV1 causing C-fibre activation and consequent oedema formation. These findings identify a novel pathway that may be useful in the therapeutics of diseases/conditions characterized by a prominent neurogenic inflammation, as in several skin diseases.
Collapse
Affiliation(s)
- Alexander Hamers
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| | - Christopher P Primus
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| | - Charlotte Whitear
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| | - Nitin Ajit Kumar
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| | - Michael Masucci
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| | - Shanik A Montalvo Moreira
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| | - Krishnaraj Rathod
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| | - Jianmin Chen
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| | - Kristen Bubb
- Monash Cardiovascular Research Centre, Monash University, Melbourne, Australia
| | - Romain Colas
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| | - Rayomand S Khambata
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| | - Jesmond Dalli
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| | - Amrita Ahluwalia
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London
| |
Collapse
|
3
|
Han GH, Chay DB, Nam S, Cho H, Chung JY, Kim JH. Prognostic Significance of Transient Receptor Potential Vanilloid Type 1 (TRPV1) and Phosphatase and Tension Homolog (PTEN) in Epithelial Ovarian Cancer. Cancer Genomics Proteomics 2020; 17:309-319. [PMID: 32345672 DOI: 10.21873/cgp.20191] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 02/22/2020] [Accepted: 03/06/2020] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Transient receptor potential vanilloid type 1 (TRPV1) has been studied in human malignancies, but has not been studied in epithelial ovarian cancer (EOC). We, therefore, investigated the significance of TRPV1 and correlation with phosphatase and tension homolog (PTEN) in EOC. MATERIALS AND METHODS Immunohistochemical analyses for TRPV1 and PTEN were performed using a tissue microarray. Moreover, the role of TRPV1 in cell growth was assessed in a EOC cell line. RESULTS High TRPV1 expression and the combination of high TRPV1 and low PTEN expression were an independent prognostic factor for overall survival and disease-free survival. In vitro results demonstrated that knockdown of TRPV1 was associated with decreased cell viability and colony formation. CONCLUSION There is a strong association between TRPV1 and PTEN and the combination of TRPV1 and PTEN is a strong indicator of prognostic predictor in EOC.
Collapse
Affiliation(s)
- Gwan Hee Han
- Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Seoul, Republic of Korea.,Department of Obstetrics and Gynecology, Kyung Hee University Hospital at Gangdong, Seoul, Republic of Korea
| | - Doo Byung Chay
- Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Sanghee Nam
- Department of Obstetrics and Gynecology, Gangnam Severance Hospital, Seoul, Republic of Korea
| | - Hanbyoul Cho
- Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Seoul, Republic of Korea .,Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, U.S.A
| | - Joon-Yong Chung
- Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, U.S.A
| | - Jae-Hoon Kim
- Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Seoul, Republic of Korea
| |
Collapse
|
4
|
Ogawa Y, Irifune M, Mukai A, Shimizu Y, Doi M, Oue K, Yoshida M, Kanematsu T, Morioka N, Nakata Y, Sakai N. The indirect γ-aminobutyric acid (GABA) receptor agonist gabaculine-induced loss of the righting reflex may inhibit the descending analgesic pathway. Pharmacol Biochem Behav 2020; 198:173034. [PMID: 32910929 DOI: 10.1016/j.pbb.2020.173034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 05/27/2020] [Accepted: 09/02/2020] [Indexed: 10/23/2022]
Abstract
In the spinal cord, γ-aminobutyric acid (GABA) interneurons play an essential role in antinociception. However, not all actions of GABA favor antinociception at the supraspinal level. We previously reported that gabaculine, which increases endogenous GABA in the synaptic clefts, induces loss of the righting reflex (LORR) that is one indicator of hypnosis, but not immobility in response to noxious stimulus. A slow pain is transmitted to the spinal cord via C fibers and evokes substance P (SP) release from their terminals. However, the antinociceptive effects of gabaculine are still unknown. Our study examined whether the analgesic effects of the opioid morphine or the α2-adrenoceptor agonist dexmedetomidine, whose actions are mediated through facilitation of the descending analgesic pathway, are affected by gabaculine-induced LORR. We also explored the effects of GABA receptor agonists on SP release from cultured dorsal root ganglion (DRG) neurons. All drugs were administered systemically to mice. To assess antinociception, loss of nociceptive response (analgesia) and immobility were evaluated. DRG cells were dissected from rats. Gabaculine produced no analgesia. Either morphine or dexmedetomidine in combination with gabaculine induced immobility; however, the doses of each drug required to induce immobility were much higher than those required to induce analgesia. Capsaicin significantly increased SP release from DRG cells, but a high concentration (1 mM) of the GABA receptor agonist muscimol, propofol, gaboxadol, or baclofen did not inhibit the capsaicin-induced SP release, suggesting that their antinociceptive effects were not through this mechanism. Thus, the gabaculine-induced LORR may inhibit the descending analgesic pathway.
Collapse
Affiliation(s)
- Yuya Ogawa
- Section of Dental Anesthesiology, Department of Oral & Maxillofacial Surgery and Oral Medicine, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Masahiro Irifune
- Department of Dental Anesthesiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan.
| | - Akari Mukai
- Department of Dental Anesthesiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Yoshitaka Shimizu
- Department of Dental Anesthesiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Mitsuru Doi
- Department of Dental Anesthesiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Kana Oue
- Section of Dental Anesthesiology, Department of Oral & Maxillofacial Surgery and Oral Medicine, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Mitsuhiro Yoshida
- Section of Dental Anesthesiology, Department of Oral & Maxillofacial Surgery and Oral Medicine, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Takashi Kanematsu
- Department of Cellular and Molecular Pharmacology, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Norimitsu Morioka
- Department of Pharmacology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Yoshihiro Nakata
- Department of Pharmacology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Norio Sakai
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| |
Collapse
|
5
|
The Combination of Transient Receptor Potential Vanilloid Type 1 (TRPV1) and Phosphatase and Tension Homolog (PTEN) is an Effective Prognostic Biomarker in Cervical Cancer. Int J Gynecol Pathol 2020; 40:214-223. [PMID: 32287115 DOI: 10.1097/pgp.0000000000000677] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Transient receptor potential vanilloid type 1 (TRPV1) has been reported to play an important role in human cancers. However, the knowledge about TRPV1 in cervical cancer is sparse. Therefore, we evaluated the expression and clinical significance of TRPV1 in cervical cancer. Immunohistochemical analyses were performed for TRPV1 and phosphatase and tension homolog (PTEN) to delineate clinical significance using 150 cervical cancers, 230 cervical intraepithelial neoplasias, and 312 normal cervical epithelial tissues in a tissue microarray. Furthermore, the role of TRPV1 in cell growth was assessed in a cervical cancer cell line. The TRPV1 expression was significantly higher in cervical cancer tissues than in cervical intraepithelial neoplasias, and normal epithelial tissues (P<0.001). In cervical cancer tissues, TRPV1 expression negatively correlated with PTEN expression (Spearman ρ=-0.121, P=0.009). Multivariate survival analysis revealed high TRPV1 expression (hazard ratio=3.41, 95% confidence interval: 1.25-9.27, P=0.016) as an independent prognostic factor for overall survival. Notably. the high TRPV1/low PTEN expression showed the highest hazard ratio (5.87; 95% confidence interval: 2.18-15.82, P<0.001) for overall survival. In vitro results demonstrated that the overexpression of TRPV1 was associated with increased cell viability and colony formation. Overexpression of TRPV1 could be a good biomarker for the prediction of chemoradiation response. Our result suggested promising potential of high TRPV1/low PTEN as prognostic and survival makers. The possible link between the biologic function of TRPV1 and PTEN in cervical cancer warrants further studies.
Collapse
|
6
|
Jiang XX, Liu GY, Lei H, Li ZL, Feng QP, Huang W. Activation of transient receptor potential vanilloid 1 protects the heart against apoptosis in ischemia/reperfusion injury through upregulating the PI3K/Akt signaling pathway. Int J Mol Med 2017; 41:1724-1730. [PMID: 29286076 DOI: 10.3892/ijmm.2017.3338] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Accepted: 12/13/2017] [Indexed: 11/06/2022] Open
Abstract
Transient receptor potential vanilloid 1 (TRPV1) is a nonselective cation channel and a molecular integrator of noxious stimuli. TRPV1 activation confers cardiac protection against ischemia/reperfusion (I/R) injury. The present study aimed to investigate whether the cardioprotective effects of TRPV1 were associated with the inhibition of apoptosis via the phosphatidylinositol 3‑kinase (PI3K)/protein kinase B (Akt) and extracellular signal‑regulated protein kinase 1/2 (ERK1/2) signaling pathways. Briefly, the hearts of TRPV1 knockout (TRPV1‑/‑) or wild‑type (WT) mice were isolated and subjected to 30 min of ischemia followed by 60 min of reperfusion in a Langendorff apparatus in the presence or absence of the PI3K inhibitor, LY294002. At the end of reperfusion, infarct size was measured using 2,3,5‑triphenyltetrazolium chloride staining and myocardial apoptosis was assessed by terminal deoxynucleotidyl transferase‑mediated dUTP nick‑end labeling (TUNEL) staining. The expression levels of B‑cell lymphoma 2 (Bcl‑2), Bcl‑2‑associated X protein (Bax), and phosphorylated Akt and ERK1/2 were determined by western blot analysis. There was a significant increase in the extent of infarction and the percentage of TUNEL‑positive cells, and a decrease in the Bcl‑2/Bax ratio, and Akt and ERK1/2 phosphorylation in TRPV1‑/‑ hearts. In addition, treatment with LY294002 increased infarct size and the percentage of TUNEL‑positive cells, and reduced Bcl‑2/Bax expression and Akt phosphorylation in WT hearts, but not in TRPV1‑/‑ hearts, following I/R. Taken together, these data suggested that TRPV1 serves a protective role against myocardial apoptosis during I/R via the PI3K/Akt signaling pathway. In conclusion, activating TRPV1 may be considered a potential approach to protect the heart against I/R injury.
Collapse
Affiliation(s)
- Xiao-Xue Jiang
- Cardiovascular Laboratory, Department of Cardiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Guan-Yu Liu
- Department of Urology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Han Lei
- Cardiovascular Laboratory, Department of Cardiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Zuo-Ling Li
- Cardiovascular Laboratory, Department of Cardiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Qing-Ping Feng
- Department of Physiology and Pharmacology, University of Western Ontario, London, ON N6A‑5C1, Canada
| | - Wei Huang
- Cardiovascular Laboratory, Department of Cardiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| |
Collapse
|
7
|
Bao Y, Gao Y, Yang L, Kong X, Yu J, Hou W, Hua B. The mechanism of μ-opioid receptor (MOR)-TRPV1 crosstalk in TRPV1 activation involves morphine anti-nociception, tolerance and dependence. Channels (Austin) 2015; 9:235-43. [PMID: 26176938 DOI: 10.1080/19336950.2015.1069450] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Initiated by the activation of various nociceptors, pain is a reaction to specific stimulus modalities. The μ-opioid receptor (MOR) agonists, including morphine, remain the most potent analgesics to treat patients with moderate to severe pain. However, the utility of MOR agonists is limited by the adverse effects associated with the use of these drugs, including analgesic tolerance and physical dependence. A strong connection has been suggested between the expression of the transient receptor potential vanilloid type 1 (TRPV1) ion channel and the development of inflammatory hyperalgesia. TRPV1 is important for thermal nociception induction, and is mainly expressed on sensory neurons. Recent reports suggest that opioid or TRPV1 receptor agonist exposure has contrasting consequences for anti-nociception, tolerance and dependence. Chronic morphine exposure modulates TRPV1 activation and induces the anti-nociception effects of morphine. The regulation of many downstream targets of TRPV1 plays a critical role in this process, including calcitonin gene-related peptide (CGRP) and substance P (SP). Additional factors also include capsaicin treatment blocking the anti-nociception effects of morphine in rats, as well as opioid modulation of TRPV1 responses through the cAMP-dependent PKA pathway and MAPK signaling pathways. Here, we review new insights concerning the mechanism underlying MOR-TRPV1 crosstalk and signaling pathways and discuss the potential mechanisms of morphine-induced anti-nociception, tolerance and dependence associated with the TRPV1 signaling pathway and highlight how understanding these mechanisms might help find therapeutic targets for the treatment of morphine induced antinociception, tolerance and dependence.
Collapse
Affiliation(s)
- Yanju Bao
- a Department of Oncology ; Guang'anmen Hospital, China Academy of Chinese Medical Sciences ; Beijing , P. R. China
| | - Yebo Gao
- a Department of Oncology ; Guang'anmen Hospital, China Academy of Chinese Medical Sciences ; Beijing , P. R. China.,b Beijing University of Chinese Medicine ; Beijing , P. R. China
| | - Liping Yang
- c Department of Nephrology ; Guang'anmen Hospital, China Academy of Chinese Medical Sciences ; Beijing , P. R. China
| | - Xiangying Kong
- d Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences ; Beijing , P. R. China
| | - Jing Yu
- e Department of Oncology ; Beijing Friendship Hospital, Capital Medical University ; Beijing , China
| | - Wei Hou
- a Department of Oncology ; Guang'anmen Hospital, China Academy of Chinese Medical Sciences ; Beijing , P. R. China
| | - Baojin Hua
- a Department of Oncology ; Guang'anmen Hospital, China Academy of Chinese Medical Sciences ; Beijing , P. R. China
| |
Collapse
|
8
|
Miyano K, Minami K, Yokoyama T, Ohbuchi K, Yamaguchi T, Murakami S, Shiraishi S, Yamamoto M, Matoba M, Uezono Y. Tramadol and its metabolite m1 selectively suppress transient receptor potential ankyrin 1 activity, but not transient receptor potential vanilloid 1 activity. Anesth Analg 2015; 120:790-8. [PMID: 25642661 DOI: 10.1213/ane.0000000000000625] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND The transient receptor potential vanilloid 1 (TRPV1) and the transient receptor potential ankyrin 1 (TRPA1), which are expressed in sensory neurons, are polymodal nonselective cation channels that sense noxious stimuli. Recent reports showed that these channels play important roles in inflammatory, neuropathic, or cancer pain, suggesting that they may serve as attractive analgesic pharmacological targets. Tramadol is an effective analgesic that is widely used in clinical practice. Reportedly, tramadol and its metabolite (M1) bind to μ-opioid receptors and/or inhibit reuptake of monoamines in the central nervous system, resulting in the activation of the descending inhibitory system. However, the fundamental mechanisms of tramadol in pain control remain unclear. TRPV1 and TRPA1 may be targets of tramadol; however, they have not been studied extensively. METHODS We examined whether and how tramadol and M1 act on human embryonic kidney 293 (HEK293) cells expressing human TRPV1 (hTRPV1) or hTRPA1 by using a Ca imaging assay and whole-cell patch-clamp recording. RESULTS Tramadol and M1 (0.01-10 μM) alone did not increase in intracellular Ca concentration ([Ca]i) in HEK293 cells expressing hTRPV1 or hTRPA1 compared with capsaicin (a TRPV1 agonist) or the allyl isothiocyanate (AITC, a TRPA1 agonist), respectively. Furthermore, in HEK293 cells expressing hTRPV1, pretreatment with tramadol or M1 for 5 minutes did not change the increase in [Ca]i induced by capsaicin. Conversely, pretreatment with tramadol (0.1-10 μM) and M1 (1-10 μM) significantly suppressed the AITC-induced [Ca]i increases in HEK293 cells expressing hTRPA1. In addition, the patch-clamp study showed that pretreatment with tramadol and M1 (10 μM) decreased the inward currents induced by AITC. CONCLUSIONS These data indicate that tramadol and M1 selectively inhibit the function of hTRPA1, but not that of hTRPV1, and that hTRPA1 may play a role in the analgesic effects of these compounds.
Collapse
Affiliation(s)
- Kanako Miyano
- From the *Division of Cancer Pathophysiology, National Cancer Center Research Institute, Chuo-ku, Tokyo, Japan; †Department of Anesthesiology and Critical Care Medicine, Jichi Medical University, Shimotsuke, Tochigi, Japan; ‡Tsumura Research Labs, Tumura & Co., Inashiki-gun, Ibaraki, Japan; §Division of Biostatistics, Tohoku University Graduate School of Medicine, Clinical Research Data Center, Tohoku University Hospital, Sendai, Miyagi, Japan; ∥Department of Palliative Medicine, Seirei Sakura Citizen Hospital, Sakura-shi, Chiba, Japan; and ¶Department of Palliative Medicine, Aomori Prefectural Central Hospital, Aomori-city, Aomori, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Up-Regulation of the Biosynthesis and Release of Substance P through Wnt/β-Catenin Signaling Pathway in Rat Dorsal Root Ganglion Cells. PLoS One 2015; 10:e0129701. [PMID: 26054011 PMCID: PMC4459973 DOI: 10.1371/journal.pone.0129701] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 05/12/2015] [Indexed: 11/19/2022] Open
Abstract
To examine regulatory effects of β-catenin on the biosynthesis and release of substance P, a rat chronic constriction injury (CCI) model and a rat dorsal root ganglion (DRG) cell culture model were used in the present study. The CCI treatment significantly induced the overall expression of β-catenin (158 ± 6% of sham) in the ipsilateral L5 DRGs in comparison with the sham group (109 ± 4% of sham). The CCI-induced aberrant expression of β-catenin was significantly attenuated by oral administration of diclofenac (119 ± 6% of the sham value; 10 mg/kg). Importantly, aberrant nuclear accumulation of β-catenin in cultured DRG cells resulted in up-regulation of the PPT-A mRNA expression and the substance P release. The up-regulation of both the PPT-A mRNA expression and the substance P release by either a GSK-3β inhibitor TWS119 (10 μM) or a Wnt signaling agonist Wnt-3a (100 ng/ml) were significantly abolished by an inhibitor of cyclooxygenase-2 (COX-2; NS-398, 1 μM). Collectively, these data suggest that nociceptive input-activated β-catenin signaling plays an important role in regulating the biosynthesis and release of substance P, which may contribute to the inflammation responses related to chronic pain.
Collapse
|
10
|
Different responses of galanin and calcitonin gene-related peptide to capsaicin stimulation on dorsal root ganglion neurons in vitro. ACTA ACUST UNITED AC 2013; 184:68-74. [PMID: 23499803 DOI: 10.1016/j.regpep.2013.03.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 02/08/2013] [Accepted: 03/03/2013] [Indexed: 11/20/2022]
Abstract
Both galanin (Gal) and calcitonin gene-related peptide (CGRP) are sensory neuropeptides which expressed in dorsal root ganglion (DRG) neurons and are involved in nociceptive processing. Capsaicin (CAP) influences nociceptive processing via influencing the expression of sensory neuropeptides in primary sensory neurons. However, little is known about the alterations of Gal and CGRP expression at the same condition stimulated by CAP. In the present study, primary cultured DRG neurons were used to determine the different responses of Gal and CGRP to CAP stimulation. DRG neurons were cultured for 48 hours and then exposed to CAP (2 μmol/L), capsazepine (CPZ) (2 μmol/L) plus CAP (2 μmol/L), or extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor PD98059 (10 μmol/L) plus CAP (2 μmol/L) for an additional 24hours. The DRG neurons were continuously exposed to culture media as a control. After that, the levels of Gal mRNA and CGRP mRNA of DRG neurons were determined using real time-PCR analysis. Gal and CGRP expression in situ was detected by an immunofluorescent labeling technique. The levels of phosphorylated-ERK1/2 (pERK1/2) protein were detected using a Western blot assay. The results showed that CAP evoked increases of Gal and its mRNA and decreases of CGRP and its mRNA in DRG neurons. Administration of either CPZ or PD98059 blocked the effects of CAP. These data indicate that Gal and CGRP shared different responses to CAP stimulation. Gal and CGRP may have different effects in nociceptive processing during neurogenic inflammation.
Collapse
|
11
|
Vellani V, Franchi S, Prandini M, Moretti S, Castelli M, Giacomoni C, Sacerdote P. Effects of NSAIDs and paracetamol (acetaminophen) on protein kinase C epsilon translocation and on substance P synthesis and release in cultured sensory neurons. J Pain Res 2013; 6:111-20. [PMID: 23429763 PMCID: PMC3575176 DOI: 10.2147/jpr.s36916] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Celecoxib, diclofenac, ibuprofen, and nimesulide are nonsteroidal anti-inflammatory drugs (NSAIDs) very commonly used for the treatment of moderate to mild pain, together with paracetamol (acetaminophen), a very widely used analgesic with a lesser anti-inflammatory effect. In the study reported here, we tested the efficacy of celecoxib, diclofenac, and ibuprofen on preprotachykinin mRNA synthesis, substance P (SP) release, prostaglandin E2 (PGE2) release, and protein kinase C epsilon (PKCɛ) translocation in rat cultured sensory neurons from dorsal root ganglia (DRGs). The efficacy of these NSAIDs was compared with the efficacy of paracetamol and nimesulide in in vitro models of hyperalgesia (investigated previously). While nimesulide and paracetamol, as in previous experiments, decreased the percentage of cultured DRG neurons showing translocation of PKCɛ caused by 100 nM thrombin or 1 μM bradykinin in a dose-dependent manner, the other NSAIDs tested did not have a significant effect. The amount of SP released by peptidergic neurons and the expression level of preprotachykinin mRNA were assessed in basal conditions and after 70 minutes or 36 hours of stimulation with an inflammatory soup (IS) containing potassium chloride, thrombin, bradykinin, and endothelin-1. The release of SP at 70 minutes was inhibited only by nimesulide, while celecoxib and diclofenac were effective at 36 hours. The mRNA basal level of the SP precursor preprotachykinin expressed in DRG neurons was reduced only by nimesulide, while the increased levels expressed during treatment with the IS were significantly reduced by all drugs tested, with the exception of ibuprofen. All drugs were able to decrease basal and IS-stimulated PGE2 release. Our study demonstrates novel mechanisms of action of commonly used NSAIDS.
Collapse
Affiliation(s)
- Vittorio Vellani
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | | | | | | | | | | | | |
Collapse
|
12
|
Munaron L, Avanzato D, Moccia F, Mancardi D. Hydrogen sulfide as a regulator of calcium channels. Cell Calcium 2013; 53:77-84. [DOI: 10.1016/j.ceca.2012.07.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 05/30/2012] [Accepted: 07/05/2012] [Indexed: 12/18/2022]
|
13
|
Nakamura Y, Une Y, Miyano K, Abe H, Hisaoka K, Morioka N, Nakata Y. Activation of transient receptor potential ankyrin 1 evokes nociception through substance P release from primary sensory neurons. J Neurochem 2012; 120:1036-47. [PMID: 22182301 DOI: 10.1111/j.1471-4159.2011.07628.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
To examine mechanisms underlying substance P (SP) release from primary sensory neurons in response to activation of the non-selective cation channel transient receptor potential ankyrin 1 (TRPA1), SP release from cultured rat dorsal root ganglion neurons was measured, using radioimmunoassay, by stimulating TRPA1 with allyl isothiocyanate (AITC), a TRPA1 agonist. AITC-evoked SP release occurred in a concentration- and time-dependent manner. Interestingly, p38 mitogen-activated protein kinase (p38) inhibitor SB203580 significantly attenuated AITC-evoked SP release. The in vivo effect of AITC-evoked SP release from primary sensory neurons in mice was evaluated. Hind paw intraplantar injection of AITC induced nociceptive behaviors and inflammation (edema, thermal hyperalgesia). AITC-induced thermal hyperalgesia and edema were inhibited by intraplantar pre-treatment with either SB203580 or neurokinin-1 receptor antagonist CP96345. Moreover, intrathecal pre-treatment with either CP96345 or SB203580 inhibited AITC-induced nociceptive behaviors and thermal hyperalgesia. Immunohistochemical studies demonstrated that intraplantar AITC injection induced the phosphorylation of p38 in mouse dorsal root ganglion neurons containing SP. These findings suggest that activation of TRPA1 evokes SP release from the primary sensory neurons through phosphorylation of p38, subsequent nociceptive behaviors and inflammatory responses. Furthermore, the data also indicate that blocking the effects of TRPA1 activation at the periphery leads to significant antinociception.
Collapse
Affiliation(s)
- Yoki Nakamura
- Department of Pharmacology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan
| | | | | | | | | | | | | |
Collapse
|
14
|
Li YS, Wang JX, Jia MM, Liu M, Li XJ, Tang HB. Dragon's blood inhibits chronic inflammatory and neuropathic pain responses by blocking the synthesis and release of substance P in rats. J Pharmacol Sci 2011; 118:43-54. [PMID: 22198006 DOI: 10.1254/jphs.11160fp] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 11/06/2011] [Indexed: 10/14/2022] Open
Abstract
As a traditional Chinese medicine, dragon's blood (DB) is widely used in treating various pains for thousands of years due to its potent anti-inflammatory and analgesic effects. In the present study, we observed that intragastric administration of DB at dosages of 0.14, 0.56, and 1.12 g/kg potently inhibited paw edema, hyperalgesia, cyclooxygenase-2 (COX-2) protein expression, or preprotachykinin-A mRNA expression in carrageenan-inflamed or sciatic nerve-injured (chronic constriction injury) rats, respectively. A short-term (15 s or 10 min) pre-exposure of cultured rat dorsal root ganglion (DRG) neurons to DB (0.3, 3, and 30 µg/ml) or its component cochinchinenin B (CB; 0.1, 1, and 10 µM) blocked capsaicin-evoked increases in both the intracellular calcium ion concentration and the substance P release. Moreover, a long-term (180 min) exposure of cultured rat DRG neurons to DB or CB significantly attenuated bradykinin-induced substance P release. These findings indicate that DB exerts anti-inflammatory and analgesic effects by blocking the synthesis and release of substance P through inhibition of COX-2 protein induction and intracellular calcium ion concentration. Therefore, DB may serve as a promising potent therapeutic agent for treatment of chronic pain, and its effective component CB might partly contribute to anti-inflammatory and analgesic effects.
Collapse
Affiliation(s)
- Yu-Sang Li
- Department of Pharmacology, College of Pharmacy, South-Central University for Nationalities, China
| | | | | | | | | | | |
Collapse
|
15
|
Vellani V, Franchi S, Prandini M, Moretti S, Pavesi G, Giacomoni C, Sacerdote P. Nimesulide inhibits protein kinase C epsilon and substance P in sensory neurons - comparison with paracetamol. J Pain Res 2011; 4:177-87. [PMID: 21811393 PMCID: PMC3141834 DOI: 10.2147/jpr.s21931] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
In this paper we describe new actions of nimesulide and paracetamol in cultured peripheral neurons isolated from rat dorsal root ganglia (DRG). Both drugs were able to decrease in a dose-dependent fashion the number of cultured DRG neurons showing translocation of protein kinase C epsilon (PKCɛ) caused by exposure to 1 μM bradykinin or 100 nM thrombin. In addition, the level of substance P (SP) released by DRG neurons and the level of preprotachykinin mRNA expression were measured in basal conditions and after 70 minutes or 36 hours of stimulation with nerve growth factor (NGF) or with an inflammatory soup containing bradykinin, thrombin, endothelin-1, and KCl. Nimesulide (10 μM) significantly decreased the mRNA levels of the SP precursor preprotachykinin in basal and in stimulated conditions, and decreased the amount of SP released in the medium during stimulation of neurons with NGF or with the inflammatory soup. The effects of paracetamol (10 μM) on such response was lower. Nimesulide completely inhibited the release of prostaglandin E2 (PGE2) from DRG neurons, either basal or induced by NGF and by inflammatory soup, while paracetamol decreased PGE2 release only partially. Our data demonstrate, for the first time, a direct effect of two drugs largely used as analgesics on DRG neurons. The present results suggest that PKCɛ might be a target for the effect of nimesulide and paracetamol, while inhibition of SP synthesis and release is clearly more relevant for nimesulide than for paracetamol mechanism of action.
Collapse
Affiliation(s)
- Vittorio Vellani
- Dipartimento di Scienze Biomediche, Università di Modena e Reggio Emilia, Modena, Italy
| | | | | | | | | | | | | |
Collapse
|
16
|
Nguyen TL, Nam YS, Lee SY, Kim HC, Jang CG. Effects of capsazepine, a transient receptor potential vanilloid type 1 antagonist, on morphine-induced antinociception, tolerance, and dependence in mice. Br J Anaesth 2010; 105:668-74. [PMID: 20719804 DOI: 10.1093/bja/aeq212] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Repeated morphine treatment has been shown to induce transient receptor potential vanilloid type 1 (TRPV1) expression in the spinal cord, dorsal root ganglion (DRG), and sciatic nerve of a rat model. Increased TRPV1 expression may therefore play a role in morphine tolerance. In this study, we evaluated the hypothesis that blockage of TRPV1 may be useful as an adjunctive pain management therapy. We investigated whether blockage of TRPV1 by capsazepine, a TRPV1 antagonist, affected antinociception, development of tolerance, and physical dependence on morphine in mice. METHODS Institute of Cancer Research mice were pretreated with capsazepine and post-treated with morphine acutely and repeatedly. Antinociception and its tolerance were assessed using the hot-plate test. Morphine dependence was examined through the manifestation of withdrawal symptoms induced by naloxone in morphine-dependent mice. RESULTS Acute capsazepine treatment (5 mg kg⁻¹, i.p.) potentiated the antinociceptive effects of morphine, as measured by the hot-plate test. Repeated co-treatment of capsazepine (2.5 mg kg⁻¹ i.p.) with morphine attenuated the development of tolerance to the antinociceptive effect of morphine. The development of morphine dependence was also reduced by capsazepine (1.25 or 2.5 mg kg⁻¹ i.p.). CONCLUSIONS Our results suggest that TRPV1 antagonists can be used adjunctively to morphine treatment because they strengthen morphine antinociception and prevent the development of tolerance, and also physical dependence, on morphine.
Collapse
Affiliation(s)
- T-L Nguyen
- Department of Pharmacology, School of Pharmacy, Sungkyunkwan University, Suwon 440-746, Republic of Korea
| | | | | | | | | |
Collapse
|
17
|
Pan XQ, Gonzalez JA, Chang S, Chacko S, Wein AJ, Malykhina AP. Experimental colitis triggers the release of substance P and calcitonin gene-related peptide in the urinary bladder via TRPV1 signaling pathways. Exp Neurol 2010; 225:262-73. [PMID: 20501335 DOI: 10.1016/j.expneurol.2010.05.012] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Revised: 05/17/2010] [Accepted: 05/18/2010] [Indexed: 12/30/2022]
Abstract
Clinical data provide evidence of high level of co-morbidity among genitourinary and gastrointestinal disorders characterized by chronic pelvic pain. The objective of this study was to test the hypothesis that colonic inflammation can impact the function of the urinary bladder via activation of TRPV1 signaling pathways followed by alterations in gene and protein expression of substance P (SP) and calcitonin gene-related peptide (CGRP) in sensory neurons and in the bladder. Inflammation was induced by intracolonic instillation of trinitrobenzene sulfonic acid (TNBS, 12.5mg/kg), and desensitization of TRPV1 receptors was evoked by intracolonic resiniferatoxin (RTX, 10(-)(7)M). mRNA and protein concentrations of CGRP and SP were measured at 3, 5 and 30 days. RTX instillation in the colon caused 3-fold up-regulation of SP mRNA in the urinary bladder at day 5 (n=7, p ≤ 0.05) followed by 35-fold increase at day 30 (n=5, p ≤ 0.05). Likewise, TNBS colitis triggered 15.8-fold up-regulation of SP mRNA 1 month after TNBS (n=5, p ≤ 0.05). Desensitization of colonic TRPV1 receptors prior to TNBS abolished SP increase in the urinary bladder. RTX led to 4.3-fold increase of CGRP mRNA at day 5 (n=7, p ≤ 0.05 to control) in the bladder followed by 28-fold increase at day 30 post-RTX (n=4, p ≤ 0.05). Colitis did not alter CGRP concentration during acute phase; however, at day 30 mRNA level was increased by 17.8 ± 6.9-fold (n=5, p ≤ 0.05) in parallel with 4-fold increase in CGRP protein (n=5, p ≤ 0.01) in the detrusor. Protein concentration of CGRP in the spinal cord was diminished by 45-65% (p ≤ 0.05) during colitis. RTX pretreatment did not affect CGRP concentration in the urinary bladder; however, it caused a reduction in CGRP release from lumbosacral DRG neurons during acute phase (3 and 5 days post-TNBS). Our results clearly demonstrate that colonic inflammation triggers the release of pro-inflammatory neuropeptides SP and CGRP in the urinary bladder via activation of TRPV1 signaling mechanisms enunciating the neurogenic nature of pelvic organ cross-sensitization.
Collapse
Affiliation(s)
- Xiao-Qing Pan
- Division of Urology, Department of Surgery, University of Pennsylvania, Glenolden, PA, USA
| | | | | | | | | | | |
Collapse
|
18
|
Ding Q, Zhang Y, Wang Y, Wang Y, Zhang L, Ding C, Wu L, Yu G. Functional Vanilloid Receptor-1 in Human Submandibular Glands. J Dent Res 2010; 89:711-6. [DOI: 10.1177/0022034510366841] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Vanilloid receptor-1 (VR1) was originally found in the nervous system. Recent evidence indicates that VR1 is also expressed in various cell types. We hypothesized that VR1 exists in the human submandibular gland (SMG) and is involved in regulating salivary secretion. VR1 mRNA and protein were expressed in human SMGs and a human salivary intercalated duct cell line. VR1 was mainly located in serous acinar and ductal cells, but not in mucous acinar cells. Capsaicin, an agonist of VR1, increased intracellular free calcium, enhanced phosphorylation of extracellular signal-regulated kinase, and induced the trafficking of aquaporin 5 (AQP5) from the cytoplasm to the plasma membrane. These effects were abolished by pre-treatment with the VR1 antagonist capsazepine. Furthermore, capsaicin cream applied to the skin covering the submandibular area increased salivary secretion. These findings indicated that a functional VR1 is expressed in the human SMG and is involved in regulating salivary secretion by mediating AQP5 trafficking.
Collapse
Affiliation(s)
- Q.W. Ding
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhong Guan Cun South St., Beijing, 100081, P.R. China
| | - Y. Zhang
- Department of Physiology and Pathophysiology, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, P.R. China
| | - Y. Wang
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhong Guan Cun South St., Beijing, 100081, P.R. China
| | - Y.N. Wang
- Department of Physiology and Pathophysiology, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, P.R. China
| | - L. Zhang
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhong Guan Cun South St., Beijing, 100081, P.R. China
| | - C. Ding
- Department of Physiology and Pathophysiology, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, P.R. China
| | - L.L. Wu
- Department of Physiology and Pathophysiology, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, P.R. China
| | - G.Y. Yu
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhong Guan Cun South St., Beijing, 100081, P.R. China
| |
Collapse
|
19
|
Miyano K, Tang HB, Nakamura Y, Morioka N, Inoue A, Nakata Y. Paclitaxel and vinorelbine, evoked the release of substance P from cultured rat dorsal root ganglion cells through different PKC isoform-sensitive ion channels. Neuropharmacology 2009; 57:25-32. [DOI: 10.1016/j.neuropharm.2009.04.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2008] [Revised: 03/09/2009] [Accepted: 04/02/2009] [Indexed: 11/28/2022]
|
20
|
Tang HB, Miyano K, Nakata Y. Modulation of the Substance P Release From Cultured Rat Primary Afferent Neurons by Zinc Ions. J Pharmacol Sci 2009; 110:397-400. [DOI: 10.1254/jphs.09033sc] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
|
21
|
Malagarie-Cazenave S, Olea-Herrero N, Vara D, Díaz-Laviada I. Capsaicin, a component of red peppers, induces expression of androgen receptor via PI3K and MAPK pathways in prostate LNCaP cells. FEBS Lett 2008; 583:141-7. [DOI: 10.1016/j.febslet.2008.11.038] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Revised: 11/19/2008] [Accepted: 11/22/2008] [Indexed: 11/29/2022]
|
22
|
Tang HB, Li YS, Miyano K, Nakata Y. Phosphorylation of TRPV1 by neurokinin-1 receptor agonist exaggerates the capsaicin-mediated substance P release from cultured rat dorsal root ganglion neurons. Neuropharmacology 2008; 55:1405-11. [DOI: 10.1016/j.neuropharm.2008.08.037] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Revised: 08/28/2008] [Accepted: 08/29/2008] [Indexed: 12/28/2022]
|
23
|
Tang HB, Shiba E, Li YS, Morioka N, Zheng TX, Ogata N, Nakata Y. Involvement of voltage-gated sodium channel Na(v)1.8 in the regulation of the release and synthesis of substance P in adult mouse dorsal root ganglion neurons. J Pharmacol Sci 2008; 108:190-7. [PMID: 18845912 DOI: 10.1254/jphs.08163fp] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
This study was conducted to determine whether Na(v)1.8 contributes to the release and/or synthesis of substance P (SP) in adult mice dorsal root ganglion (DRG) neurons. The SP released from cultured DRG neurons of Na(v)1.8 knock-out mice exposed to either capsaicin or KCl was significantly lower than that from wild-type (C57BL/6) mice based on a radioimmunoassay. The SP level of L6 DRG in Na(v)1.8 knock-out mice was also lower than that in wild-type mice. After chronic constriction injury (CCI) of the sciatic nerve, the level of SP decreased in the L6 ipsilateral DRG of wild-type but not Na(v)1.8 knock-out mice. The preprotachykinin-A (PPT-A) mRNAs in L4 - 6 DRGs of Na(v)1.8 knock-out mice also fell to half their normally abundant levels of expression. There were significant increases in Na(v)1.8 expression of the L6 contralateral DRG from wild-type mice and in the percentage of neurons expressing neurokinin-1 receptor in the cytosol of L6 DRGs from wild-type or Na(v)1.8 knock-out mice. These findings suggest that Na(v)1.8 is involved in the regulation of the release and synthesis of SP in the DRG neurons of wild-type mice.
Collapse
Affiliation(s)
- He-Bin Tang
- Department of Pharmacology, Graduate School of Biomedical Sciences, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima, Japan
| | | | | | | | | | | | | |
Collapse
|