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Ul Haq I, Ahmad T, Khan T, Shah AJ. Antihypertensive effect and the underlying mechanisms of action of phytolaccagenin in rat models. Clin Exp Hypertens 2022; 44:557-566. [DOI: 10.1080/10641963.2022.2079671] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Imran Ul Haq
- Department of Pharmacy, COMSATS University Islamabad, Abbottabad, Pakistan
| | - Taseer Ahmad
- Department of Pharmacology, College of Pharmacy, University of Sargodha, University Road, Sargodha, Pakistan
| | - Taous Khan
- Department of Pharmacy, COMSATS University Islamabad, Abbottabad, Pakistan
| | - Abdul Jabbar Shah
- Department of Pharmacy, COMSATS University Islamabad, Abbottabad, Pakistan
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Ul Haq I, Khan T, Ahmad T, Shah AJ. Insight into the cardiovascular mechanisms of blood pressure lowering effect of gitogenin: a steroidal saponin. Clin Exp Hypertens 2021; 43:723-729. [PMID: 34396877 DOI: 10.1080/10641963.2021.1950748] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Background/objectives: Steroidal saponins are widely distributed in medicinal plants with potential applications in cardiovascular disorders. Gitogenin, a saponin, has not been explored as antihypertensive; this investigation was aimed to explore its blood pressure lowering potential and underlying mechanisms.Methodology: The effect of gitogenin was evaluated on blood pressure in vivo, using normotensive rat model and the underlying cardiovascular mechanism(s) in vitro, in isolated rat aorta and in atria preparations using PowerLab data acquisition system (ADInstrument, Australia).Results: Intravenous injection of gitogenin decreased mean arterial pressure (MAP) in anesthetized rats. Atropine (1 mg/kg) and L-NAME (100 mg/kg) pretreatment significantly (*p < .05) attenuated effect on MAP to gitogenin. In isolated intact aortic rings, gitogenin induced endothelium-dependent vasodilatation (maximum 65%), which was ablated (maximum 22%) with L-NAME (100 mg/kg) and atropine (1 μM) pretreatment or endothelium removal. Gitogenin was found more potent against angiotensin II precontractions without effect on high K+ and low K+ precontractions. In isolated rat right atria, gitogenin suppressed rate and force of contractions. Atropine (1 μM) pretreatment partially inhibited effect of gitogenin on force and eliminated its effect on rate. Combined atropine (10 μM) and atenolol (0.5 μM) pretreatment was without effect on force of contractions but eliminated effect of gitogenin on rate with 25% increase.Conclusion: These findings indicate that antihypertensive effect of gitogenin is the outcome of vascular and cardiac effects; agonistic effect on vascular M3 and cardiac M2 receptors; and being more selective for M2. Increase in the rate of atrial contraction might be of clinical importance.
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Affiliation(s)
- Imran Ul Haq
- Department of Pharmacy, COMSATS University Islamabad, KP, Pakistan
| | - Taous Khan
- Department of Pharmacy, COMSATS University Islamabad, KP, Pakistan
| | - Taseer Ahmad
- Department of Pharmacy, COMSATS University Islamabad, KP, Pakistan
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Mussa BM, Srivastava A, Mohammed AK, Verberne AJM. Nitric oxide interacts with cholinoceptors to modulate insulin secretion by pancreatic β cells. Pflugers Arch 2020; 472:1469-1480. [PMID: 32803305 PMCID: PMC7476970 DOI: 10.1007/s00424-020-02443-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 07/17/2020] [Accepted: 07/31/2020] [Indexed: 01/09/2023]
Abstract
Dysfunction of the pancreatic β cells leads to several chronic disorders including diabetes mellitus. Several mediators and mechanisms are known to be involved in the regulation of β cell secretory function. In this study, we propose that cytokine-induced nitric oxide (NO) production interacts with cholinergic mechanisms to modulate insulin secretion from pancreatic β cells. Using a rat insulinoma cell line INS-1, we demonstrated that β cell viability decreases significantly in the presence of SNAP (NO donor) in a concentration- and time-dependent manner. Cell viability was also found to be decreased in the presence of a combined treatment of SNAP with SMN (muscarinic receptor antagonist). We then investigated the impact of these findings on insulin secretion and found a significant reduction in glucose uptake by INS-1 cells in the presence of SNAP and SMN as compared with control. Nitric oxide synthase 3 gene expression was found to be significantly reduced in response to combined treatment with SNAP and SMN suggesting an interaction between the cholinergic and nitrergic systems. The analysis of gene and protein expression further pin-pointed the involvement of M3 muscarinic receptors in the cholinergic pathway. Upon treatment with cytokines, reduced cell viability was observed in the presence of TNF-α and IFN-γ. A significant reduction in insulin secretion was also noted after treatment with TNF-α and IFN-γ and IL1-β. The findings of the present study have shown for the first time that the inhibition of the excitatory effects of cholinergic pathways on glucose-induced insulin secretion may cause β cell injury and dysfunction of insulin secretion in response to cytokine-induced NO production.
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Affiliation(s)
- Bashair M Mussa
- Basic Medical Science Department, College of Medicine, University of Sharjah, P.O. Box: 27272, Sharjah, United Arab Emirates.
| | - Ankita Srivastava
- Sharjah Institute for Medical Research, University of Sharjah, P.O. Box: 27272, Sharjah, United Arab Emirates
| | - Abdul Khader Mohammed
- Sharjah Institute for Medical Research, University of Sharjah, P.O. Box: 27272, Sharjah, United Arab Emirates
| | - Anthony J M Verberne
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, 3084, Australia
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Zn 2+ stimulates salivary secretions via metabotropic zinc receptor ZnR/GPR39 in human salivary gland cells. Sci Rep 2019; 9:17648. [PMID: 31776425 PMCID: PMC6881433 DOI: 10.1038/s41598-019-54173-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 11/06/2019] [Indexed: 12/19/2022] Open
Abstract
Zn2+ is a divalent cation that is essential for many biological activities, as it influences many ion channels and enzymatic activities. Zn2+ can evoke G-protein-coupled receptor signaling via activation of the metabotropic zinc receptor ZnR/GPR39. In spite of evidence suggesting the presence of ZnR/GPR39 in salivary gland cells, there has been no evidence of ZnR/GPR39-mediated modulation of salivary gland function. Here we characterized the role of ZnR/GPR39 in human submandibular gland cells. A 0.25% ZnCl2 solution evoked secretion of unstimulated and stimulated whole saliva in humans. We found that ZnR/GPR39 is expressed in human submandibular glands and HSG cells. Zn2+ increased cytosolic Ca2+ concentration ([Ca2+]i) in a concentration-dependent manner. Muscarinic antagonist had no effect on Zn2+-induced [Ca2+]i increase, which was completely blocked by the phospholipase C-β inhibitor. As with muscarinic agonist, Zn2+ also induced the translocation of aquaporin-5 (AQP-5) to the plasma membrane, which was drastically decreased in ZnR/GPR39-knockdown cells. These data suggest that the metabotropic Zn2+ receptor ZnR/GPR39 can modulate salivary secretion in human submandibular gland cells independent of muscarinic or histamine receptor signaling.
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Bragiel AM, Wang D, Pieczonka TD, Shono M, Ishikawa Y. Mechanisms Underlying Activation of α₁-Adrenergic Receptor-Induced Trafficking of AQP5 in Rat Parotid Acinar Cells under Isotonic or Hypotonic Conditions. Int J Mol Sci 2016; 17:ijms17071022. [PMID: 27367668 PMCID: PMC4964398 DOI: 10.3390/ijms17071022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 06/15/2016] [Accepted: 06/23/2016] [Indexed: 11/18/2022] Open
Abstract
Defective cellular trafficking of aquaporin-5 (AQP5) to the apical plasma membrane (APM) in salivary glands is associated with the loss of salivary fluid secretion. To examine mechanisms of α1-adrenoceptor (AR)-induced trafficking of AQP5, immunoconfocal microscopy and Western blot analysis were used to analyze AQP5 localization in parotid tissues stimulated with phenylephrine under different osmolality. Phenylephrine-induced trafficking of AQP5 to the APM and lateral plasma membrane (LPM) was mediated via the α1A-AR subtype, but not the α1B- and α1D-AR subtypes. Phenylephrine-induced trafficking of AQP5 was inhibited by ODQ and KT5823, inhibitors of nitric oxide (NO)-stimulated guanylcyclase (GC) and protein kinase (PK) G, respectively, indicating the involvement of the NO/ soluble (c) GC/PKG signaling pathway. Under isotonic conditions, phenylephrine-induced trafficking was inhibited by La3+, implying the participation of store-operated Ca2+ channel. Under hypotonic conditions, phenylephrine-induced trafficking of AQP5 to the APM was higher than that under isotonic conditions. Under non-stimulated conditions, hypotonicity-induced trafficking of AQP5 to the APM was inhibited by ruthenium red and La3+, suggesting the involvement of extracellular Ca2+ entry. Thus, α1A-AR activation induced the trafficking of AQP5 to the APM and LPM via the Ca2+/ cyclic guanosine monophosphate (cGMP)/PKG signaling pathway, which is associated with store-operated Ca2+ entry.
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Affiliation(s)
- Aneta M Bragiel
- Department of Medical Pharmacology, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15, Kuramoto-cho, Tokushima 770-8504, Japan.
| | - Di Wang
- Department of Medical Pharmacology, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15, Kuramoto-cho, Tokushima 770-8504, Japan.
| | - Tomasz D Pieczonka
- Department of Medical Pharmacology, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15, Kuramoto-cho, Tokushima 770-8504, Japan.
| | - Masayuki Shono
- Support Center for Advanced Medical Sciences, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15, Kuramoto-cho, Tokushima 770-8504, Japan.
| | - Yasuko Ishikawa
- Department of Medical Pharmacology, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15, Kuramoto-cho, Tokushima 770-8504, Japan.
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Moustafa A, Habara Y. Hydrogen sulfide: a novel gaseous signaling molecule and intracellular Ca2+ regulator in rat parotid acinar cells. Am J Physiol Cell Physiol 2015. [DOI: 10.1152/ajpcell.00147.2015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In addition to nitric oxide (NO), hydrogen sulfide (H2S) is recognized as a crucial gaseous messenger that exerts many biological actions in various tissues. An attempt was made to assess the roles and underlying mechanisms of both gases in isolated rat parotid acinar cells. Ductal cells and some acinar cells were found to express NO and H2S synthases. Cevimeline, a muscarinic receptor agonist upregulated endothelial NO synthase in parotid tissue. NO and H2S donors increased the intracellular Ca2+ concentration ([Ca2+]i). This was not affected by inhibitors of phospholipase C and inositol 1,4,5-trisphosphate receptors, but was decreased by blockers of ryanodine receptors (RyRs), soluble guanylyl cyclase, and protein kinase G. The H2S donor evoked NO production, which was decreased by blockade of NO synthases or phosphoinositide 3-kinase or by hypotaurine, an H2S scavenger. The H2S donor-induced [Ca2+]i increase was diminished by a NO scavenger or the NO synthases blocker. These results suggest that NO and H2S play important roles in regulating [Ca2+]i via soluble guanylyl cyclase-cGMP-protein kinase G-RyRs, but not via inositol 1,4,5-trisphosphate receptors. The effect of H2S may be partially through NO produced via phosphoinositide 3-kinase-Akt-endothelial NO synthase. It was concluded that both gases regulate [Ca2+]i in a synergistic way, mainly via RyRs in rat parotid acinar cells.
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Affiliation(s)
- Amira Moustafa
- Laboratory of Physiology, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan; and
- Department of Physiology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Yoshiaki Habara
- Laboratory of Physiology, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan; and
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Production and physiological role of NO in the oral cavity. JAPANESE DENTAL SCIENCE REVIEW 2015; 52:14-21. [PMID: 28408951 PMCID: PMC5382787 DOI: 10.1016/j.jdsr.2015.08.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 07/24/2015] [Accepted: 08/20/2015] [Indexed: 12/28/2022] Open
Abstract
Nitric oxide (NO) is a free radical which is produced from a wide variety of cells and tissues in the human body. NO is involved in the regulation of many physiological processes, such as vascular relaxation, neurotransmission, immune regulation, and cell death. NO is generated by nitric oxide synthase (NOS), which has three identified isoforms: neuronal type NOS (nNOS), endothelial type NOS (eNOS), and inducible type NOS (iNOS). Different isoforms are expressed depending on the organs, tissues, and cells, and investigation of the types and functions of enzymes expressed in various tissues is underway. The oral cavity is a space in which marked changes have been detected in NO levels, and each tissue is constantly influenced by NO. NO is a component of saliva and is produced by oral bacteria in the oral cavity and released by NOS expressed in oral mucosa. NOS isoforms expressed under normal conditions differ among the oral organs. In addition, the overexpression of NOS was involved in carcinogenesis and tumor growth progression. This review summarized the expression of NOS and functions of NO in oral cavity organs, and their roles in diseases and the influences of treatments.
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Hassan SS, Rachakatla R, McGarvey T, Youakeem MF. Morphological changes in the salivary acini after in vivo cholinergic stimulation. Neurourol Urodyn 2015; 35:574-81. [PMID: 25810148 DOI: 10.1002/nau.22768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 02/26/2015] [Indexed: 11/11/2022]
Abstract
AIMS Overactive bladder syndrome treated by muscarinic receptor antagonists may be complicated by reduced salivation. Cholinergic agonists may reverse this effect. The aim of the present study was to determine the antagonizing effect of a cholinergic agonist (carbachol) on a muscarinic receptor antagonist (oxybutynin) in the submandibular acini in a rat model. METHODS Forty male Sprague Dawley rats were divided into three groups: Group I (control), Group II (vehicle), and Group III (treatment). Group III was subdivided so Group IIIa was treated with a muscarinic receptor antagonist (oxybutynin) for 1 week, Group IIIb was treated with oxybutynin for 3 weeks, and Group IIIc was treated with oxybutynin for 1 week and oxybutynin and a cholinergic agonist (carbachol) for 2 weeks. Histological and ultrastructural studies were performed on submandibular glands. RESULTS Group IIIa showed moderate atrophic changes in the serous acini and ducts. Group IIIb showed serous acini with distorted wall, widening of the inter-lobar space, and deposition of mononuclear cells in the connective tissue. Group IIIc had serous acini similar to Group I, with mildly dilated inter-lobar ducts, but some serous acini revealed double nuclei and the inter-lobar duct showed luminal vacuolations. Ultrastructural studies confirmed histological results. CONCLUSIONS Muscarinic receptor antagonist administration led to changes in the submandibular gland of rats, while concomitant administration of cholinergic agonists seemed to counteract these atrophic changes. Additional studies should assess carbachol as a cholinergic agonist in treating dry mouth in patients with overactive bladder syndrome who are taking the muscarinic receptor. Neurourol. Urodynam. 35:574-581, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Sherif S Hassan
- Department of Anatomy, A.T. Still University, Kirksville College of Osteopathic Medicine, Kirksville, Missouri.,Department of Anatomy, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Raja Rachakatla
- Department of Anatomy, A.T. Still University, Kirksville College of Osteopathic Medicine, Kirksville, Missouri
| | - Terence McGarvey
- Department of Anatomy, A.T. Still University, Kirksville College of Osteopathic Medicine, Kirksville, Missouri
| | - Magdy F Youakeem
- Department of Anatomy, Faculty of Medicine, Cairo University, Cairo, Egypt
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Lanzafame AA, Christopoulos A, Mitchelson F. Cellular Signaling Mechanisms for Muscarinic Acetylcholine Receptors. ACTA ACUST UNITED AC 2011. [DOI: 10.3109/10606820308263] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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10
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Li GQ, Correia MJ. Responses of pigeon vestibular hair cells to cholinergic agonists and antagonists. Brain Res 2010; 1373:25-38. [PMID: 21147073 DOI: 10.1016/j.brainres.2010.12.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 12/03/2010] [Accepted: 12/06/2010] [Indexed: 10/18/2022]
Abstract
Acetylcholine (ACh) is the major neurotransmitter released from vestibular efferent terminals onto hair cells and afferents. Previous studies indicate that the two classes of acetylcholine receptors, nicotinic (nAChRs) and muscarinic receptors (mAChRs), are expressed by vestibular hair cells (VHCs). To identify if both classes of receptors are present in VHCs, whole cell, voltage-clamp- and current-clamp-patch recordings were performed on isolated pigeon vestibular type I and type II HCs during the application of the cholinergic agonists, acetylcholine and carbachol, and the cholinergic antagonists, D-tubocurarine and atropine. By applying in different combinations, these compounds were used to selectively activate either nAChRs or mAChRs. The effects of nAChR and mAChR activation on HC currents and zero electrode current potential (V(z)) were monitored. It was found that presumed mAChR activation decreased both inward and outward currents in both type I and type II HCs, resulting in either a depolarization or hyperpolarization. Conversely, nAChR activation mainly increased both inward and outward currents in type II HCs, resulting in a hyperpolarization of their V(z). nAChR activation also increased outward currents in type I HCs resulting in either a depolarization or hyperpolarization of their V(z). The decrease of inward and outward currents and the depolarization of the V(z) in type I pigeon HCs by activation of mAChRs represents a new finding. Ion channel candidates in pigeon vestibular HCs that might underlie the modulation of the macroscopic ionic currents and V(z) by different AChR activation are discussed.
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Affiliation(s)
- Gang Q Li
- Department of Otolaryngology, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77550-1063, USA
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11
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Cabadak H, Küçükibrahimoğlu E, Aydın B, Kan B, Zafer Gören M. Muscarinic receptor-mediated nitric oxide release in a K562 erythroleukaemia cell line. ACTA ACUST UNITED AC 2009; 29:109-15. [DOI: 10.1111/j.1474-8673.2009.00431.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Calafat M, Larocca L, Roca V, Hauk V, Pregi N, Nesse A, Pérez Leirós C. Vasoactive intestinal peptide inhibits TNF-alpha-induced apoptotic events in acinar cells from nonobese diabetic mice submandibular glands. Arthritis Res Ther 2009; 11:R53. [PMID: 19356238 PMCID: PMC2688204 DOI: 10.1186/ar2671] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 04/01/2009] [Accepted: 04/08/2009] [Indexed: 12/23/2022] Open
Abstract
Introduction The role of apoptotic secretory epithelium as a pro-inflammatory triggering factor of exocrine dysfunction is currently explored in Sjogren's syndrome patients and in the nonobese diabetic (NOD) mouse model. Vasoactive intestinal peptide (VIP) has anti-inflammatory effects in various models of chronic inflammation. Our goal was to analyse the effect of TNF-α on apoptotic mediators in isolated acinar cells from NOD submandibular gland and their modulation by VIP. Methods Acinar cells were isolated from submandibular glands of 16-week-old NOD females with salivary flow decline. Age-matched BALB/c females or eight-week-old NOD females were used as controls. Apoptotic mediators and TNF-α receptor expression were assessed by immunoblotting and RT-PCR, caspase 3 activity was assessed by optical density at 405 nm with Ac-DEVD-pNA as a substrate and chromatin condensation by Hoechst stain. They were evaluated in resting conditions and after a 3.5 or 6 hours of culture with TNF-α. VIP effects in acinar cells were assessed at 100 nM in TNF-α-treated cultures and VIP receptor functional assays by radio immunoassay (cAMP) or enzymatic detection (amylase). Results NOD acinar cells at 16 weeks present an increased expression of TNF-α receptor1 together with increased Bax, tumour protein 53-induced nuclear protein1α (TP53INP1α), caspase 3 activity and chromatin condensation. Acini from NOD mice were more sensitive to TNF-α-induced increases of apoptotic mediators than control cells. VIP inhibited TNF-α-induced apoptotic events through functional VPAC1 receptors coupled to the protein kinase A (PKA) signalling pathway. Conclusions Our results indicate that acinar cells isolated from submandibular glands of NOD mice with salivary dysfunction are more sensitive to apoptosis induced by TNF-α which could be prevented by VIP through a PKA-mediated pathway.
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Affiliation(s)
- Mario Calafat
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón II, Buenos Aires, Argentina.
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Berggreen E, Nyløkken K, Delaleu N, Hajdaragic-Ibricevic H, Jonsson MV. Impaired vascular responses to parasympathetic nerve stimulation and muscarinic receptor activation in the submandibular gland in nonobese diabetic mice. Arthritis Res Ther 2009; 11:R18. [PMID: 19200376 PMCID: PMC2688250 DOI: 10.1186/ar2609] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Revised: 01/22/2009] [Accepted: 02/06/2009] [Indexed: 12/02/2022] Open
Abstract
Introduction Decreased vascular responses to salivary gland stimulation are observed in Sjögren's syndrome patients. We investigate whether impaired vascular responses to parasympathetic stimulation and muscarinic receptor activation in salivary glands parallels hyposalivation in an experimental model for Sjögren's syndrome. Methods Blood flow responses in the salivary glands were measured by laser Doppler flowmeter. Muscarinic receptor activation was followed by saliva secretion measurements. Nitric oxide synthesis-mediated blood flow responses were studied after administration of a nitric oxide synthase inhibitor. Glandular autonomic nerves and muscarinic 3 receptor distributions were also investigated. Results Maximal blood flow responses to parasympathetic stimulation and muscarinic receptor activation were significantly lower in nonobese diabetic (NOD) mice compared with BALB/c mice, coinciding with impaired saliva secretion in nonobese diabetic mice (P < 0.005). Nitric oxide synthase inhibitor had less effect on blood flow responses after parasympathetic nerve stimulation in nonobese diabetic mice compared with BALB/c mice (P < 0.02). In nonobese diabetic mice, salivary gland parasympathetic nerve fibres were absent in areas of focal infiltrates. Muscarinic 3 receptor might be localized in the blood vessel walls of salivary glands. Conclusions Impaired vasodilatation in response to parasympathetic nerve stimulation and muscarinic receptor activation may contribute to hyposalivation observed in nonobese diabetic mice. Reduced nitric oxide signalling after parasympathetic nerve stimulation may contribute in part to the impaired blood flow responses. The possibility of muscarinic 3 receptor in the vasculature supports the notion that muscarinic 3 receptor autoantibodies present in nonobese diabetic mice might impair the fluid transport required for salivation. Parasympathetic nerves were absent in areas of focal infiltrates, whereas a normal distribution was found within glandular epithelium. Trial registration The trial registration number for the present study is 79-04/BBB, given by the Norwegian State Commission for Laboratory Animals.
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Affiliation(s)
- Ellen Berggreen
- Department of Biomedicine, Jonas Liesvei 91, Bergen 5009, Norway.
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Issy AC, da Silva CA, Guimarães FS, Del Bel EA. Different role of isoproterenol and NOS inhibitors on salivary ducts of rats. Micron 2009; 40:343-9. [PMID: 19167231 DOI: 10.1016/j.micron.2008.10.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Revised: 10/13/2008] [Accepted: 10/14/2008] [Indexed: 11/19/2022]
Abstract
OBJECTIVES Nitric oxide (NO) is a diffusible intracellular messenger that is present in saliva. Chronic treatment with isoproterenol, a beta receptor agonist, stimulates the release of NO from acinar cells and induces salivary gland hypertrophy. The aim of this study was to investigate the effect of NO synthesis inhibitors and isoproterenol on rat salivary glands. We analyzed salivary gland weight and the number of ducts per unit area (0.5mm(2)) by NADPH-diaphorase histochemistry (to identify the presence of the enzyme NO synthase-NOS) and haematoxylin-and-eosin (HE). METHODS For 8 days male Wistar rats received daily single intraperitoneal injections of saline or a NOS inhibitor (40mg/kg N(omega)-nitro-L-arginine L-NOARG or N(omega)-nitro-l-arginine methyl ester L-NAME). This was followed, 30min later, by subcutaneous injection of isoproterenol (2 or 5mg/kg) or saline. RESULTS Isoproterenol increased parotid and submandibular gland weights. Isoproterenol (2mg/kg) induced a decrease of ducts per unit area inversely correlated to the weight of the parotid gland. This effect was augmented by L-NAME. In the submandibular gland L-NAME attenuated isoproterenol (2mg/kg) weight increase. In the submandibular gland isoproterenol and NOS inhibitors induced an increase in ducts per unit area (HE and NADPH-diaphorase). No effect was observed in the sublingual gland. CONCLUSION To our knowledge this is the first description of isoproterenol and NOS inhibitors increasing duct density in the submandibular gland. Our results corroborate the hypothesis that NO plays different roles in parotid and submandibular glands.
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Affiliation(s)
- A C Issy
- Department of Pharmacology, University of São Paulo, Av. Bandeirantes 13400, 14049-900 Ribeirão Preto, SP, Brazil
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Nakaya M, Kondo K, Kaga K. Immunohistochemical study of m1-m5 muscarinic receptors and nNOS in human inferior turbinate mucosa. Acta Otolaryngol 2007:103-7. [PMID: 18340579 DOI: 10.1080/03655230701599321] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
CONCLUSION This study suggested that nitric oxide (NO) takes part in the parasympathetic nerve control functions mainly through m3 receptors and subsequently through m1 receptors. OBJECTIVES The regulation of glandular secretions and vasomotor tone in human nasal mucosa implicates muscarinic receptors. There are five recognized classes (m1-m5) of muscarinic receptor subtypes. NO is a free radical gas that has been found to be produced in neuronal cells by the action of enzyme neural nitric oxide synthase (nNOS). The aim of this study was to identify the colocalization of muscarinic receptor subtypes (m1-m5) and nNOS in the human inferior turbinate mucosa. MATERIALS AND METHODS Human inferior turbinate mucosa was stained by using the antibody of muscarine receptor subtypes and nNOS in an immunohistochemical double-staining method. RESULTS The colocalization of m3 receptors and nNOS-immunoreactive nerve fibers was most extensively distributed on glands, vessels, and epithelium in all muscarinic receptor subtypes. These findings lead us to propose that NO also acts as a neurotransmitter in glands, vessels, and epithelium of the human nasal mucosa and can be assigned to parasympathetic nerve structures through m3 receptors mainly and m1 receptors subsequently.
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Calafat M, Larocca L, Roca V, Pérez Leirós C. NOD mice exocrinopathy: towards a neuroimmune link. Neuroimmunomodulation 2007; 14:175-81. [PMID: 18073511 DOI: 10.1159/000110643] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Sjogren's syndrome (SS) is a chronic autoimmune disorder of exocrine glands characterized as an autoimmune exocrinopathy and more specifically as an autoimmune epithelitis. An impaired balance of neuroimmune interactions mediated by vasoactive intestinal peptide (VIP) in the target organ at early stages of disease is explored by means of the nonobese diabetic (NOD) mouse model of SS. We have previously described a reduced salivary secretion and signaling upon VIP stimulation. The effect reflected a differential regulation of the neural isoform of nitric oxide synthase by calcium calmodulin kinase II and occurred prior to the appearance of detectable levels of cytokines in NOD glands. VIP acting on NOD macrophages treated with lipopolysaccharide promoted anti-inflammatory effects by inhibiting nitric oxide synthase induction as well as IL-12 and TNF-alpha production, while stimulating IL-10. Here we present evidence on the ability of apoptotic acinar cells from submandibular glands of NOD mice to stimulate nitric oxide in both peritoneal and glandular macrophage pools to a similar extent as lipopolysaccharide + IFN-gamma. VIP was not effective to prevent nitrite accumulation and modestly increased IL-10 levels in macrophages coincubated with acinar cells. An enhanced nitrite response of NOD glandular macrophages in basal and stimulated conditions compared to peritoneal cells is also shown.
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Affiliation(s)
- Mario Calafat
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
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Busch L, Sterin-Borda L, Borda E. An Overview of Autonomic Regulation of Parotid Gland Activity: Influence of Orchiectomy. Cells Tissues Organs 2006; 182:117-28. [PMID: 16914915 DOI: 10.1159/000093962] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2006] [Indexed: 11/19/2022] Open
Abstract
The parotid gland participates in the digestive process by providing fluid, electrolytes and enzymes that facilitate the onset of digestion. Neurotransmitters, hormones and biologically active peptides regulate its activity. The autonomic system is the main regulatory mechanism of the gland. Sympathetic stimulation induces amylase release through beta(1)-receptor activation and few fluid secretion by alpha(1)-receptor activation. The parasympathetic system controls basal activity of the gland acting on M(1) and M(3) muscarinic acetylcholine receptors and induces the secretion of fluid saliva rich in electrolytes through the modulation of ion channels and the Na(+)-K(+)-ATPase activity. In addition, its activation induces amylase release. The mechanisms involved in amylase secretion by isoproterenol and carbachol, as well as the mechanism of the cholinergic regulation of Na(+)-K(+)-ATPase activity and the changes observed after orchiectomy, are the scope of this review.
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Affiliation(s)
- Lucila Busch
- Pharmacology Unit, University of Buenos Aires School of Dentistry, Buenos Aires, Argentina.
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Costa MA, Elesgaray R, Balaszczuk AM, Arranz C. Role of NPR-C natriuretic receptor in nitric oxide system activation induced by atrial natriuretic peptide. ACTA ACUST UNITED AC 2006; 135:63-8. [PMID: 16712979 DOI: 10.1016/j.regpep.2006.04.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Revised: 04/04/2006] [Accepted: 04/09/2006] [Indexed: 11/15/2022]
Abstract
Atrial natriuretic peptide (ANP) exerts its hypotensive, natriuretic and diuretic effects, almost in part, through the activation of nitric oxide synthase (NOS). The aim was to investigate the natriuretic receptor type and the signaling cascade involved in NOS activation induced by ANP. Male Wistar rats were sacrificed and NOS activity was determined in kidney, aorta and heart with L-[U14C]-arginine, as substrate. ANP and cANP (4-23), a selective NPR-C ligand, increased NOS activity in all tissues. ANP induced a more marked activation in aorta and kidney than cANP (4-23), but no difference in atria NOS activation was observed. NOS activity induced by both peptides was blunted by nifedipine (L-type channel blocker) and calmidazolium (calmodulin antagonist) in heart and aorta. In kidney, nifedipine and calmidazolium abolished NOS activity stimulated by cANP (4-23) but only partially inhibited NOS activity elicited by ANP. Gi inhibition with pertussis toxin abolished NOS activity stimulated by ANP and cANP in atria but only partially inhibited the increased NOS activity induced by ANP and cANP in kidney, aorta and ventricle. Our results show that NPR-C receptor would mediate the activation of NOS by ANP in atria. In kidney, aorta and ventricle, NOS activation would also involve NPR-A and/or B. ANP would interact with NPR-C coupled via Gi to activation Ca2+ -dependent NOS.
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Affiliation(s)
- María Angeles Costa
- Cátedra de Fisiología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, IQUIMEFA-CONICET, Junín 956, piso 7, 1113 Capital Federal, Argentina.
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Tomat AL, Weisstaub AR, Jauregui A, Piñeiro A, Balaszczuk AM, Costa MA, Arranz CT. Moderate zinc deficiency influences arterial blood pressure and vascular nitric oxide pathway in growing rats. Pediatr Res 2005; 58:672-6. [PMID: 16189192 DOI: 10.1203/01.pdr.0000180540.55990.eb] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
There is an increasing interest in the involvement of trace elements such as zinc in the pathogenesis of cardiovascular diseases. This study was designed to examine whether moderate zinc deficiency during growth influences blood pressure (BP) and vascular nitric oxide (NO) pathway. Three-week-old weaned male Wistar rats were randomly divided into two dietary groups and fed either a moderately zinc-deficient diet (zinc content 9 mg/kg; n = 12) or a control diet (zinc content 30 mg/kg; n = 12) for 60 d. The following were measured: systolic BP, nitrates and nitrites urinary excretion, urinary chemiluminescence intensity, NADPH-diaphorase activity in the thoracic aorta and intestinal arterioles, and NO synthase (NOS) catalytic activity using L-[U14C]-arginine as substrate in the thoracic aorta. Zinc deficiency during growth induced an increase in BP from day 30 of the experimental period, leading to hypertension on day 60. Animals that were fed the zinc-deficient diet had lower urinary excretion levels of nitrates and nitrites and higher intensity of spontaneous luminescence on day 60. At the end of the experiment, zinc-deficient rats showed decreased NADPH diaphorase activity in endothelium and smooth muscle of the thoracic aorta and intestinal arterioles and decreased activity of NOS in thoracic aortic tissue. An imbalance in zinc bioavailability during postnatal and growing periods may be may be a risk factor in development of cardiovascular alterations in adult life. The mechanisms involved may include an impaired vascular NO system as a result of decreased NOS activity and higher systemic oxidative stress.
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Affiliation(s)
- Analía L Tomat
- Cátedra de Fisiología, Universidad de Buenos Aires, Argentina
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20
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Roca V, Rosignoli F, Calafat M, Leirós CP. Lack of nitric oxide-mediated regulation of amylase secretion stimulated by VIP in parotid glands of NOD mice. Int Immunopharmacol 2005; 4:1837-44. [PMID: 15531299 DOI: 10.1016/j.intimp.2004.08.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2004] [Revised: 06/29/2004] [Accepted: 08/10/2004] [Indexed: 10/26/2022]
Abstract
The non-obese diabetic (NOD) mouse is chosen among other experimental models to study autoimmune sialadenitis resembling Sjögren's syndrome (SS), because of its unique characteristic of developing salivary dysfunction. Based on the deep loss of nitric oxide synthase (NOS) activity in parotid glands of NOD mice observed from early stages of disease and the inhibitory effect of nitric oxide (NO) donors on amylase secretion in normal salivary glands, our goal was to investigate whether parotid glands from NOD mice lacking NOS activity presented this regulatory mechanism of amylase secretion. We found that parotid glands from NOD mice lack nitric oxide-mediated regulation of amylase secretion in response to VIP stimulation. The lack of regulation might be assigned to the loss of NOS activity as derived from the results with NOS inhibitors and increasing concentrations of VIP. These functional differences observed in NOD vs. BALB/c parotid glands occur in the absence of immune infiltrates in exocrine tissue, and it is not related to cAMP accumulation. NO-mediated regulation of amylase secretion was not observed in BALB/c submandibular glands to the same extent as described in parotid glands and was absent in submandibular glands of NOD mice.
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Affiliation(s)
- Valeria Roca
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires-CONICET, Buenos Aires, Argentina
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21
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Costa MA, Loria A, Elesgaray R, Balaszczuk AM, Arranz C. Role of nitric oxide pathway in hypotensive and renal effects of furosemide during extracellular volume expansion. J Hypertens 2005; 22:1561-9. [PMID: 15257180 DOI: 10.1097/01.hjh.0000125445.28861.8a] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE In previous studies we demonstrated that the administration of furosemide associated with L-arginine contributes to enhanced hypotension and induces greater water than electrolyte excretion, in both normal and expansion conditions. The aim of the present study was to elucidate the interaction between furosemide and the nitric oxide (NO) system in renal and vascular responses during extracellular volume expansion. DESIGN AND METHODS Expanded [10% body weight (bw)] and non-expanded anaesthetized male Wistar rats were treated with furosemide (7.5 mg/kg bw). Mean arterial pressure, nitrite and nitrate excretion (NOx) were determined. NADPH-diaphorase activity, a marker of nitric oxide synthase (NOS) activity, was measured histochemically in different segments of the nephron, aorta and renal arteries. NOS activity was determined using an L-[U14C]-arginine substrate in the kidney and aorta of expanded and non-expanded rats, in basal conditions and after furosemide (10 micromol/l). RESULTS The hypotensive effect of furosemide was enhanced when NO production was stimulated in expanded and non-expanded animals. The diuretic treatment induced a significant increase in NOx excretion, in NADPH-diaphorase activity in the thick ascending limb of Henle, renal arteries and aorta, and in NOS activity in aorta and kidney in both groups. CONCLUSIONS Our results suggest that the hypotensive effect of furosemide may be attributed to NO-mediated vasodilation. The enhanced NOS activity, observed in the renal artery of furosemide-treated rats, could explain the increased renal plasma flow induced by furosemide. In addition, NO-pathway stimulation in the kidney could be one of the mechanisms by which furosemide exerts its diuretic and natriuretic effects, in control and in expansion conditions.
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Affiliation(s)
- María A Costa
- Cátedra de Fisiología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, IQUIMEFA-CONICET, Capital Federal, Argentina.
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22
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Shimomura H, Tanaka S, Komine N, Shimooka S, Imai A, Nashida T. Soluble guanylyl cyclase is localised in the acinar cells and participates in amylase secretion in rat parotid gland. Arch Oral Biol 2004; 49:691-6. [PMID: 15275856 DOI: 10.1016/j.archoralbio.2004.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/05/2004] [Indexed: 11/30/2022]
Abstract
It is well known that the muscarinic cholinergic agonists, carbachol and methacholine, enhance nitric oxide synthase (NOS) activity, and also stimulate salivary secretion. In the present study, we investigated whether salivary secretion by muscarinic cholinergic stimulation is mediated through the NO/cGMP signaling pathway in rat salivary glands. Since NO activates soluble guanylyl cyclase (sGC) and cGMP may function as a mediator, the localisation of sGC was investigated in the salivary glands. sGC was localized in both the acinar and duct cells of the rat parotid and sublingual glands, and localized only in the acinar cells of the submandibular glands. S-Nitroso-glutathione (NO generator; GSNO) and YC-1 (NO-independent sGC activator) stimulated sGC in the cytosol to synthesise cGMP. The combination of GSNO and YC-1 stimulated sGC synergistically. Carbachol, GSNO and YC-1 enhanced amylase release from the rat parotid glands. Amylase release stimulated by carbachol and GSNO was inhibited by addition of the sGC inhibitor, ODQ, and cGMP-dependent protein kinase inhibitor, KT-5823. These results indicate that amylase release may be mediated through the NO/cGMP signaling pathway.
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Affiliation(s)
- Hiromi Shimomura
- Department of Biochemistry, The Nippon Dental University at Niigata, 1-8 Hamaura-cho, 951-8580, Japan.
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Rosignoli F, Roca V, Meiss R, Pregi N, Leirós CP. Inhibition of calcium-calmodulin kinase restores nitric oxide production and signaling in submandibular glands of a mouse model of salivary dysfunction. Br J Pharmacol 2004; 143:1058-65. [PMID: 15533891 PMCID: PMC1575950 DOI: 10.1038/sj.bjp.0705952] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2004] [Accepted: 07/13/2004] [Indexed: 11/08/2022] Open
Abstract
Nitric oxide is an intracellular and diffusible messenger of neurotransmitters involved in salivary secretion, as well as an inflammatory mediator in salivary gland diseases. It is synthesized by three different isoforms of nitric oxide synthase (NOS), each subject to a fine transcriptional, post-transcriptional and/or post-translational regulation. Our purpose was to study the possible mechanisms leading to NOS downregulation in submandibular glands of normal mice and in the nonobese diabetic (NOD) mouse model of salivary dysfunction with lower NOS activity. NOS activity and cGMP accumulation were determined by radioassays in submandibular glands of both mice in the presence of the protein kinase inhibitors KN-93 and bisindolylmaleimide. NOS I mRNA and protein expression and localization were assessed by RT-PCR, Western blot and immunohistochemistry. A downregulatory effect of calcium-calmodulin kinase II (CaMK II) on NOS activity in submandibular glands of both NOD and BALB/c mice was observed. Our results are consistent with a physiological regulation of NOS activity by this kinase but not by PKC in normal BALB/c mice. They are also supportive of a role for CaMK II in the lack of detectable NOS activity in submandibular glands of NOD mice. KN-93 also restored cGMP accumulation in NOD submandibular glands. The downregulation of NOS in NOD mice seems to be mainly mediated by this kinase rather than the result of a lower expression or different cellular localization of the enzyme. It was not related to different substrate or cofactors availability either.
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Affiliation(s)
- Florencia Rosignoli
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires – CONICET, Argentina
| | - Valeria Roca
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires – CONICET, Argentina
| | - Roberto Meiss
- Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Nicolás Pregi
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires – CONICET, Argentina
| | - Claudia Pérez Leirós
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires – CONICET, Argentina
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24
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Busch L, Sterin-Borda L, Borda E. Expression and biological effects of CB1 cannabinoid receptor in rat parotid gland. Biochem Pharmacol 2004; 68:1767-74. [PMID: 15450942 DOI: 10.1016/j.bcp.2004.06.029] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2004] [Accepted: 06/23/2004] [Indexed: 02/08/2023]
Abstract
Experiments were designed to determine whether cannabinoids affect salivary gland function. For this purpose, the effect of anandamide on cAMP accumulation, amylase release and Na+-K+-ATPase activity was studied in rat parotid glands. Anandamide induced a concentration-dependent increase in cAMP and led to amylase release but inhibited Na+-K+-ATPase activity. These effects were blocked by the CB1 cannabinoid receptor antagonist, AM281. The inhibition of adenylyl cyclase activity by SQ 22536 impaired amylase release and Na+-K+-ATPase inhibition. The effect of anandamide on cAMP accumulation significantly correlated with its action either on amylase release or on Na+-K+-ATPase activity. Such correlation strongly supports the view that the effect of anandamide on amylase release and Na+-K+-ATPase activity is the result of cAMP accumulation. The relative potencies of the CB1 cannabinoid receptor antagonist, AM281, to block these three functional responses were similar, supporting the view that anandamide actions in parotid glands were achieved through a single receptor subtype, the CB1. Binding studies using the selective cannabinoid CB1 receptor antagonist, [3H]SR141716A, indicated the presence of the specific binding site. It may be concluded that in parotid glands the endogenous cannabinoid anandamide, bound to the CB1 cannabinoid receptor subtype, induces cAMP accumulation which in turn leads to amylase release and Na+-K+-ATPase inhibition.
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Affiliation(s)
- Lucila Busch
- Pharmacology Unit, School of Dentistry, University of Buenos Aires and Argentine National Research 2142, 4to "B" (1122AAH) Buenos Aires, Argentina.
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25
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Nesterova LA, Manukhin BN. Effect of the NO donor sodium nitroprusside and the NO-synthase inhibitor L-NOARG on the binding of [3H]quinuclidinyl benzylate by muscarinic cholinoreceptors of the rat cerebral cortex. DOKLADY BIOLOGICAL SCIENCES : PROCEEDINGS OF THE ACADEMY OF SCIENCES OF THE USSR, BIOLOGICAL SCIENCES SECTIONS 2003; 391:322-5. [PMID: 14556522 DOI: 10.1023/a:1025146432735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- L A Nesterova
- Kol'tsov Institute of Developmental Biology, Russian Academy of Sciences, ul. Vavilova 26, Moscow, 119991 Russia
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Tsunoda S, Michikawa H, Furuyama S, Sugiya H. Evidence that nitric oxide does not directly contribute to methacholine-induced amylase secretion in rabbit parotid acinar cells. Pflugers Arch 2003; 446:470-4. [PMID: 12684800 DOI: 10.1007/s00424-003-1055-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2002] [Accepted: 03/05/2003] [Indexed: 10/26/2022]
Abstract
Nitric oxide (NO) is a short-lived free radical and is a widespread intra- and intercellular messenger molecule involved in various physiological functions. We have demonstrated previously that the muscarinic agonist methacholine induces endogenous generation of NO in rabbit parotid acinar cells. Since methacholine also simultaneously evokes amylase secretion, we investigated the effect of NO on the methacholine-induced exocytotic amylase secretion in rabbit parotid acinar cells. Methacholine-evoked amylase secretion was clearly reduced in the absence of extracellular Ca(2+). The Ca(2+)-mobilizing reagents A23187 and thapsigargin, which stimulate NO generation, also evoked amylase secretion. This response seemed to be caused by NO generated by the activation of endogenous Ca(2+)-regulated NO synthase. However, N(G)-nitro-L-arginine methyl ester (L-NAME), a specific NOS inhibitor, and the NO scavenger haemoglobin had no effect on methacholine-induced amylase secretion. The NO generator sodium nitroprusside (SNP) failed to evoke amylase release. We further studied the effects of L-NAME and SNP on methacholine-induced amylase secretion in crudely dispersed parotid gland cell clusters containing nerve tissue. In this preparation, L-NAME inhibited methacholine-induced amylase secretion and SNP evoked amylase secretion. It is thus unlikely that NO contributes directly to methacholine-induced amylase secretion in rabbit parotid acinar cells. NO appears rather to affect to nerve tissues in the cell suspension.
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Affiliation(s)
- Shoji Tsunoda
- Department of Physiology, Nihon University School of Dentistry at Matsudo, Chiba 271-858 Matsudo, Japan
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27
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Busch L, Borda E. Castration decreases amylase release associated with muscarinic acetylcholine receptor downregulation in rat parotid gland. Br J Pharmacol 2003; 139:399-407. [PMID: 12770945 PMCID: PMC1573856 DOI: 10.1038/sj.bjp.0705260] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2002] [Revised: 02/21/2003] [Accepted: 02/25/2003] [Indexed: 11/09/2022] Open
Abstract
1 The mechanism and receptor subtypes involved in carbachol-stimulated amylase release and its changes after castration were studied in parotid slices from male rats. 2 Carbachol induced both amylase release and inositol phosphate (IP) accumulation in parotid slices from control and castrated rats, but castration induced a decrease of carbachol maximal effect. The effect of castration was reverted by testosterone replacement. 3 The selective M(1) and M(3) muscarinic receptor antagonists, pirenzepine and 4-diphenylacetoxy-N-methylpiperidine methiodide, respectively, inhibited carbachol-stimulated amylase release and IP accumulation in a dose-dependent manner in parotid slices from control and castrated rats. 4 A diminution of binding sites of muscarinic receptor in parotid membrane from castrated rats was observed. Competition binding assays showed that both, M(1) and M(3) muscarinic receptor subtypes are expressed in membranes of parotid glands from control and castrated rats, M(3) being the greater population. 5 These results suggest that amylase release induced by carbachol in parotid slices is mediated by phosphoinositide accumulation. This mechanism appears to be triggered by the activation of M(1) and M(3) muscarinic receptor subtypes. Castration induced a decrease of the maximal effect of carbachol evoked amylase release and IP accumulation followed by a diminution in the number of parotid gland muscarinic acetylcholine receptors.
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Affiliation(s)
- Lucila Busch
- Cátedra de Farmacología, Facultad de Odontología, Universidad de Buenos Aires, Argentina.
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28
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Yuan Z, Iida H, Inoue N, Ishikawa Y, Ishida H. Effect of SNI-2011 on amylase secretion from parotid tissue in rats and in neuronal nitric oxide synthase knockout mice. Eur J Pharmacol 2003; 464:197-206. [PMID: 12620514 DOI: 10.1016/s0014-2999(03)01375-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The effect of (+/-)cis-2-methylspilo(1,3-oxathiolane-5,3')quinuclidine (SNI-2011) on the secretory pathway of amylase in parotid tissues was investigated. SNI-2011-induced exocytosis was inhibited by a cell-permeable Ca(2+) chelator or inhibitors of calmodulin kinase II, neuronal nitric oxide synthase (nNOS), soluble guanyl cyclase, cyclic GMP-dependent protein kinase (PKG), and myosin light chain kinase, suggesting that these enzymes were coupled with the exocytosis. Stimulation with SNI-2011 of isolated rat parotid acinar cells loaded with 4,5-diaminofluorescein/diacetate (DAF-2/DA) induced a fast increase in DAF fluorescence corresponding to an increase in the NO production. SNI-2011-induced amylase secretion from parotid tissues in nNOS knockout mice has not been observed yet in spite of the expression of muscarinic M(3) receptors and the maintenance of secretory response to isoproterenol in the tissues. These results indicate the implication of the activation of Ca(2+)- and calmodulin-dependent enzymes and NOS-PKG signaling pathway in SNI-2011-induced amylase secretion from parotid acinar cells.
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Affiliation(s)
- Zhenfang Yuan
- Department of Pharmacology, Tokushima University School of Dentistry, Kuramoto-cho, Tokushima City, Japan
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29
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Rosignoli F, Pérez Leirós C. Nitric oxide synthase I and VIP-activated signaling are affected in salivary glands of NOD mice. J Neuroimmunol 2002; 130:109-16. [PMID: 12225893 DOI: 10.1016/s0165-5728(02)00223-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The autoimmune sialadenitis developed by non-obese diabetic (NOD) mice is considered a suitable model to study the ethiopathogenic mechanisms leading to sicca symptoms in Sjögren's syndrome (SS). Evidence supporting a neural rather than immune origin of the secretory dysfunction has been provided. As both nitric oxide and vasoactive intestinal peptide (VIP) are common messengers to nervous and immune systems mediating secretory and inflammatory responses, we examined nitric oxide synthase (NOS) activity with special focus on VIP-mediated effects in salivary glands of NOD mice. We found a decreased NOS activity and expression in major salivary glands of NOD mice with respect to control mice. In addition, there was a deficient VIP-activated signaling associated with a reduced saliva and amylase secretion in response to VIP. Our results support the hypothesis of an impaired balance of neuroimmune interactions in salivary glands as early events to take place in the progressive loss of secretory function of NOD mice.
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Affiliation(s)
- Florencia Rosignoli
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires-CONICET, Buenos Aires, Argentina
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