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Gemba C, Nakayama K, Nakamura S, Mochizuki A, Inoue M, Inoue T. Involvement of histaminergic inputs in the jaw-closing reflex arc. J Neurophysiol 2015; 113:3720-35. [PMID: 25904711 DOI: 10.1152/jn.00515.2014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 04/20/2015] [Indexed: 11/22/2022] Open
Abstract
Histamine receptors are densely expressed in the mesencephalic trigeminal nucleus (MesV) and trigeminal motor nucleus. However, little is known about the functional roles of neuronal histamine in controlling oral-motor activity. Thus, using the whole-cell recording technique in brainstem slice preparations from Wistar rats aged between postnatal days 7 and 13, we investigated the effects of histamine on the MesV neurons innervating the masseter muscle spindles and masseter motoneurons (MMNs) that form a reflex arc for the jaw-closing reflex. Bath application of histamine (100 μM) induced membrane depolarization in both MesV neurons and MMNs in the presence of tetrodotoxin, whereas histamine decreased and increased the input resistance in MesV neurons and MMNs, respectively. The effects of histamine on MesV neurons and MMNs were mimicked by an H1 receptor agonist, 2-pyridylethylamine (100 μM). The effects of an H2 receptor agonist, dimaprit (100 μM), on MesV neurons were inconsistent, whereas MMNs were depolarized without changes in the input resistance. An H3 receptor agonist, immethridine (100 μM), also depolarized both MesV neurons and MMNs without changing the input resistance. Histamine reduced the peak amplitude of postsynaptic currents (PSCs) in MMNs evoked by stimulation of the trigeminal motor nerve (5N), which was mimicked by 2-pyridylethylamine but not by dimaprit or immethridine. Moreover, 2-pyridylethylamine increased the failure rate of PSCs evoked by minimal stimulation and the paired-pulse ratio. These results suggest that histaminergic inputs to MesV neurons through H1 receptors are involved in the suppression of the jaw-closing reflex although histamine depolarizes MesV neurons and/or MMNs.
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Affiliation(s)
- Chikako Gemba
- Department of Oral Physiology, Showa University School of Dentistry, Shinagawa-ku, Tokyo, Japan; Department of Pediatric Dentistry, Showa University School of Dentistry, Oota-ku, Tokyo, Japan
| | - Kiyomi Nakayama
- Department of Oral Physiology, Showa University School of Dentistry, Shinagawa-ku, Tokyo, Japan
| | - Shiro Nakamura
- Department of Oral Physiology, Showa University School of Dentistry, Shinagawa-ku, Tokyo, Japan
| | - Ayako Mochizuki
- Department of Oral Physiology, Showa University School of Dentistry, Shinagawa-ku, Tokyo, Japan
| | - Mitsuko Inoue
- Department of Pediatric Dentistry, Showa University School of Dentistry, Oota-ku, Tokyo, Japan
| | - Tomio Inoue
- Department of Oral Physiology, Showa University School of Dentistry, Shinagawa-ku, Tokyo, Japan
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Tang M, Tian Y, Li D, Lv J, Li Q, Kuang C, Hu P, Wang Y, Wang J, Su K, Wei L. TNF-α mediated increase of HIF-1α inhibits VASP expression, which reduces alveolar-capillary barrier function during acute lung injury (ALI). PLoS One 2014; 9:e102967. [PMID: 25051011 PMCID: PMC4106849 DOI: 10.1371/journal.pone.0102967] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 06/25/2014] [Indexed: 12/21/2022] Open
Abstract
Acute lung injury (ALI) is an inflammatory disorder associated with reduced alveolar-capillary barrier function and increased pulmonary vascular permeability. Vasodilator-stimulated phosphoprotein (VASP) is widely associated with all types of modulations of cytoskeleton rearrangement-dependent cellular morphology and function, such as adhesion, shrinkage, and permeability. The present studies were conducted to investigate the effects and mechanisms by which tumor necrosis factor-alpha (TNF-α) increases the tight junction permeability in lung tissue associated with acute lung inflammation. After incubating A549 cells for 24 hours with different concentrations (0–100 ng/mL) of TNF-α, 0.1 to 8 ng/mL TNF-α exhibited no significant effect on cell viability compared with the 0 ng/mL TNF-α group (control group). However, 10 ng/mL and 100 ng/mL TNF-α dramatically inhibited the viability of A549 cells compared with the control group (*p<0.05). Monolayer cell permeability assay results indicated that A549 cells incubated with 10 ng/mL TNF-α for 24 hours displayed significantly increased cell permeability (*p<0.05). Moreover, the inhibition of VASP expression increased the cell permeability (*p<0.05). Pretreating A549 cells with cobalt chloride (to mimic a hypoxia environment) increased protein expression level of hypoxia inducible factor-1α (HIF-1α) (*p<0.05), whereas protein expression level of VASP decreased significantly (*p<0.05). In LPS-induced ALI mice, the concentrations of TNF-α in lung tissues and serum significantly increased at one hour, and the value reached a peak at four hours. Moreover, the Evans Blue absorption value of the mouse lung tissues reached a peak at four hours. The HIF-1α protein expression level in mouse lung tissues increased significantly at four hours and eight hours (**p<0.001), whereas the VASP protein expression level decreased significantly (**p<0.01). Taken together, our data demonstrate that HIF-1α acts downstream of TNF-α to inhibit VASP expression and to modulate the acute pulmonary inflammation process, and these molecules play an important role in the impairment of the alveolar-capillary barrier.
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Affiliation(s)
- Mengjie Tang
- Department of Pathology and Pathophysiology, Research Center of Food and Drug Evaluation, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, PR China
- Hunan Provincial Tumor Hospital, the Affiliated Tumor Hospital of Xiangya Medical School of Central South University, Changsha, Hunan, PR China
| | - Yihao Tian
- Department of Pathology and Pathophysiology, Research Center of Food and Drug Evaluation, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Doulin Li
- Department of Pathology and Pathophysiology, Research Center of Food and Drug Evaluation, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Jiawei Lv
- Zhongnan Hospital of Wuhan University, the Second College of Clinical Medicine of Wuhan University, Wuhan, Hubei, PR China
| | - Qun Li
- Renmin Hospital of Wuhan University, the First College of Clinical Medicine of Wuhan University, Wuhan, Hubei, PR China
| | - Changchun Kuang
- Department of Pathology and Pathophysiology, Research Center of Food and Drug Evaluation, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Pengchao Hu
- Department of Pathology and Pathophysiology, Research Center of Food and Drug Evaluation, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Ying Wang
- Department of Pathology and Pathophysiology, Research Center of Food and Drug Evaluation, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Jing Wang
- Department of Pathology and Pathophysiology, Research Center of Food and Drug Evaluation, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Ke Su
- Renmin Hospital of Wuhan University, Division of Nephrology, Wuhan, Hubei, PR China
| | - Lei Wei
- Department of Pathology and Pathophysiology, Research Center of Food and Drug Evaluation, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, PR China
- * E-mail:
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Zheng YF, Dai DZ, Dai Y. NaHS ameliorates diabetic vascular injury by correcting depressed connexin 43 and 40 in the vasculature in streptozotocin-injected rats. J Pharm Pharmacol 2010; 62:883-9. [DOI: 10.1211/jpp.62.05.0009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Li Q, Zhang J, Wang W, Liu J, Zhu H, Chen W, Chen T, Yu S, Wang H, Sun G, Yi D. Connexin40 modulates pulmonary permeability through gap junction channel in acute lung injury after thoracic gunshot wounds. THE JOURNAL OF TRAUMA 2010; 68:802-9. [PMID: 20386276 DOI: 10.1097/ta.0b013e3181bb80ea] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The permeability of pulmonary microvessel endothelial cells increases markedly after acute lung injury via paracellular gap. Connexin40 is a primary component of pulmonary microvessel endothelial cells gap junction channel and mediates intercellular communication. However, the relationship between connexin40 and the permeability of pulmonary microvessel endothelial cells is still unknown. Therefore, we determined whether connexin40 affected rabbits' pulmonary microvessel endothelial cells permeability after acute lung injury induced by gunshot trauma. METHODS We used an acute lung injury model in New Zealand rabbits following gunshot chest trauma and correlated connexin40 immunohistochemistry in gunshot lung tissue with Evans blue leak rate. Cultured pulmonary microvessel endothelial cells were divided into three groups, control (G control), injured serum (G serum), and blocker agent (G blocker). Gap junction channel function was assessed by scrape-loading and dye transfer techniques. Pulmonary microvessel endothelial cells permeability was measured by Evans blue-labeled albumin transfer. RESULTS Connexin40 expression decreased time dependently, whereas Evans blue leak rate increased. Connexin40 expression and Evans blue leak rate exhibited a strong inverse correlation (gamma = -0.934, p < 0.05). Injured serum decreased gap junction channel function, and the gap junction channel blocker aggravated this effect. Similarly, pulmonary microvessel endothelial cells permeability increased significantly in G serum and G blocker. CONCLUSIONS Connexin 40 expression in pulmonary microvasculature endothelial cells is downregulated after acute lung injury induced by gunshot trauma. This is associated with impaired gap junction channel function and increased pulmonary microvessel endothelial cells permeability.
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Affiliation(s)
- Qiang Li
- Department of Cardiovascular Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
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Van Deusen MB, Lyon MJ. Connexins within the rat larynx. Otolaryngol Head Neck Surg 2009; 139:823-8. [PMID: 19041510 DOI: 10.1016/j.otohns.2008.08.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2008] [Revised: 06/18/2008] [Accepted: 08/13/2008] [Indexed: 10/21/2022]
Abstract
OBJECTIVES/HYPOTHESIS To determine the types and localization of connexins within the rat larynx. STUDY DESIGN Quantitative real time polymerase chain reaction (qRT-PCR) of the epiglottis and laryngeal mucosa was used to identify connexins (Cx). Immunohistochemical labeling was then used to localize the Cxs within the larynx. METHODS Twelve larynges from 3 to 4 month old Fisher-344 rats were used. RNA was extracted (N = 8) and cDNA produced. Primers for Cx26, Cx30, Cx32, Cx37, Cx40, and Cx43 were added and qRT-PCR performed. Others larynges were serially sectioned for immunohistochemistry. RESULTS qRT-PCR revealed Cx43, Cx32, and Cx30 within the epiglottis and Cx43 in the vocal folds and Cx43 and Cx32 within the subglottic mucosa. Immunohistochemical staining confirmed these results. CONCLUSION The rat epiglottis is rich in Cx43, Cx32, and Cx30 whereas the vocal folds contain Cx43 and the subglottic mucosa Cx43 and Cx32. Their localizations suggest involvement in secretion for protective purposes and they may play a key role in laryngeal pathoses.
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Affiliation(s)
- Mark B Van Deusen
- Department of Otolaryngology and Communication Sciences, SUNY Upstate Medical University, Syracuse, NY 13210, USA
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Abstract
Direct intercellular communication via gap junctions is critical in the control and coordination of vascular function. In the cardiovascular system, gap junctions are made up of one or more of four connexin proteins: Cx37, Cx40, Cx43, and Cx45. The expression of more than one gap-junction protein in the vasculature is not redundant. Rather, vascular connexins work in concert, first during the development of the cardiovascular system, and then in integrating smooth muscle and endothelial cell function, and in coordinating cell function along the length of the vessel wall. In addition, connexin-based channels have emerged as an important signaling pathway in the astrocyte-mediated neurovascular coupling. Direct electrical communication between endothelial cells and vascular smooth muscle cells via gap junctions is thought to play a relevant role in the control of vasomotor tone, providing the signaling pathway known as endothelium-derived hyperpolarizing factor (EDHF). Consistent with the importance of gap junctions in the regulation of vasomotor tone and arterial blood pressure, the expression of connexins is altered in diseases associated with vascular complications. In this review, we discuss the participation of connexin-based channels in the control of vascular function in physiologic and pathologic conditions, with a special emphasis on hypertension and diabetes.
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Affiliation(s)
- Xavier F Figueroa
- Departamento de Ciencias Fisiológicas, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.
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Shi X, Han W, Yamamoto H, Tang W, Lin X, Xiu R, Trune DR, Nuttall AL. The cochlear pericytes. Microcirculation 2008; 15:515-29. [PMID: 19086261 DOI: 10.1080/10739680802047445] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVES Cochlear pericytes are not well characterized. The aim of this study was to further advance the characterization of cochlear pericyte location and distribution, with particular focus on pericyte-related proteins on the capillaries of the cochlear lateral wall that are functionally integral to structure, contraction, and gap junction transport. MATERIALS AND METHODS Cochlear pericytes were identified by the immunofluorescence labeling of pericyte marker proteins, including alpha-smooth muscle actin (alpha-SMA), desmin, Thy-1, tropomyosin, and NG2, and by morphological identification, using fluorescence, electron, and differential interference contrast microscopy. RESULTS Pericytes were predominately found in the capillary network of the cochlear lateral wall, with considerable morphological heterogeneity across different types of microvessels. For example, pericytes on the vessels of the spiral ligament (V/SL) strongly expressed a gap junction protein, connexin 40, and were positive for alpha-SMA, tropomyosin, and desmin. In contrast, pericytes on the vessels of the stria vascularis (V/SV) were positive for desmin, and were negative for alpha-SMA and tropomyosin. CONCLUSIONS The capillary networks of the cochlear lateral wall comprise a rich population of pericytes. These pericytes are morphologically heterogeneous, with protein expression potentially indicative of function.
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Affiliation(s)
- Xiaorui Shi
- Oregon Hearing Research Center (NRC04), Oregon Health & Science University, Portland, Oregon 97239-3098, USA.
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Salameh A, Dhein S. Pharmacology of gap junctions. New pharmacological targets for treatment of arrhythmia, seizure and cancer? BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2005; 1719:36-58. [PMID: 16216217 DOI: 10.1016/j.bbamem.2005.09.007] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2005] [Revised: 08/25/2005] [Accepted: 09/06/2005] [Indexed: 11/26/2022]
Abstract
Intercellular communication in many organs is maintained via intercellular gap junction channels composed of connexins, a large protein family with a number of isoforms. This gap junction intercellular communication (GJIC) allows the propagation of action potentials (e.g., in brain, heart), and the transfer of small molecules which may regulate cell growth, differentiation and function. The latter has been shown to be involved in cancer growth: reduced GJIC often is associated with increased tumor growth or with de-differentiation processes. Disturbances of GJIC in the heart can cause arrhythmia, while in brain electrical activity during seizures seems to be propagated via gap junction channels. Many diseases or pathophysiological conditions seem to be associated with alterations of gap junction protein expression. Thus, depending on the target disease opening or closure of gap junctions may be of interest, or alteration of connexin expression. GJIC can be affected acutely by changing gap junction conductance or--more chronic--by altering connexin expression and membrane localisation. This review gives an overview on drugs affecting GJIC.
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Affiliation(s)
- Aida Salameh
- Clinic I for Internal Medicine, Department of Cardiology, University of Leipzig, Johannisallee 32, 04103 Leipzig, Germany.
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