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Chowdhury VS, Ouchi Y, Haraguchi S, Bungo T. Liver metabolomic analysis in broiler chicks: Profiling the metabolites after oral administration of l-citrulline. Anim Sci J 2021; 92:e13609. [PMID: 34402126 DOI: 10.1111/asj.13609] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/19/2021] [Accepted: 07/09/2021] [Indexed: 11/29/2022]
Abstract
Hypothermia is directly linked to metabolism; however, it is still unknown how the overall metabolism is altered by oral administration of hypothermic agent, l-citrulline (l-Cit). The present study aimed to determine the characteristics of liver metabolites of chicks orally administered l-Cit to provide a greater understanding of its metabolism. Capillary electrophoresis-time-of-flight mass spectrometry (CE-TOFMS) and liquid chromatography-time-of-flight mass spectrometry (LC-TOFMS) were conducted on liver samples after oral administration of l-Cit. A total of 361 liver metabolites were identified. Although a small number of samples were used for each group, a principal component analysis and heatmap patterns confirmed that the composition of metabolites could be segregated from each other. Of the 361 compounds detected in the liver, 41 compounds, including amino acids related to the Cit-arginine (Arg) cycle, argininosuccinic acid, Arg, ornithine, and Cit, as well as gamma aminobutyric acid, glycine, histidine, and nicotinamide adenine dinucleotide were abundant in l-Cit-treated livers. In contrast, 24 compounds containing fatty acids, amino acids, and cyclic adenosine monophosphate were lower in the l-Cit group. These data imply that the active Cit-Arg cycle, TCA cycle metabolism, and a low activity in fatty acid metabolism occur in l-Cit-treated broiler chicks.
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Affiliation(s)
- Vishwajit S Chowdhury
- Division for Experimental Natural Science, Faculty of Arts and Science, Kyushu University, Fukuoka, Japan
| | - Yoshimitsu Ouchi
- Department of Bioresource Science, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Shogo Haraguchi
- Department of Biochemistry, Showa University School of Medicine, Tokyo, Japan
| | - Takashi Bungo
- Department of Bioresource Science, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
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2
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Ouchi Y, Chowdhury VS, Cockrem JF, Bungo T. Effects of Thermal Conditioning on Changes in Hepatic and Muscular Tissue Associated With Reduced Heat Production and Body Temperature in Young Chickens. Front Vet Sci 2021; 7:610319. [PMID: 33537354 PMCID: PMC7847892 DOI: 10.3389/fvets.2020.610319] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 12/08/2020] [Indexed: 11/13/2022] Open
Abstract
Effects of increased summer temperatures on poultry production are becoming more pronounced due to global warming, so it is important to consider approaches that might reduce heat stress in chickens. Thermal conditioning in chickens in the neonatal period can improve thermotolerance and reduce body temperature increases when birds are exposed to high ambient temperature later in life. The objective of this study was to investigate physiological and molecular changes associated with heat production and hence body temperature regulation under high ambient temperatures in thermally conditioned chicks. Three-day-old broiler chicks (Chunky) were thermally conditioned by exposure to a high ambient temperature (40°C) for 12 h while control chicks were kept at 30°C. Four days after the treatment, both groups were exposed to 40°C for 15 or 90 min. The increase in rectal temperature during 90 min of exposure to a high ambient temperature was less in thermally conditioned than control chicks. At 15-min of re-exposure treatment, gene expression for uncoupling protein and carnitine palmitoyletransferase 1, key molecules in thermogenesis and fatty acid oxidation, were significantly higher in pectoral muscle of control chicks but not conditioned chicks. Hepatic argininosuccinate synthase (ASS) decreased and hepatic argininosuccinate lyase (ASL) increased after reexposure to a high temperature. The concentrations of hepatic arginosuccinic acid, and ASS and ASL expression, were upregulated in conditioned chicks compared with the control chicks, indicating activity of the urea cycle could be enhanced to trap more energy to reduce heat production in conditioned chicks. These results suggest thermal conditioning can reduce the increase in heat production in muscles of chickens that occurs in high ambient temperatures to promote sensible heat loss. Conditioning may also promote energy trapping process in the liver by altering the heat production system, resulting in an alleviation of the excessive rise of body temperature.
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Affiliation(s)
- Yoshimitsu Ouchi
- Laboratory of Animal Behavior and Physiology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Vishwajit S Chowdhury
- Division for Experimental Natural Science, Faculty of Arts and Science, Kyushu University, Fukuoka, Japan
| | - John F Cockrem
- School of Veterinary Science, Massey University, Palmerston North, New Zealand
| | - Takashi Bungo
- Laboratory of Animal Behavior and Physiology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
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3
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Ali A, Wang Y, Wu L, Yang G. Gasotransmitter signaling in energy homeostasis and metabolic disorders. Free Radic Res 2020; 55:83-105. [PMID: 33297784 DOI: 10.1080/10715762.2020.1862827] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Gasotransmitters are small molecules of gases, including nitric oxide (NO), hydrogen sulfide (H2S), and carbon monoxide (CO). These three gasotransmitters can be endogenously produced and regulate a wide range of pathophysiological processes by interacting with specific targets upon diffusion in the biological media. By redox and epigenetic regulation of various physiological functions, NO, H2S, and CO are critical for the maintenance of intracellular energy homeostasis. Accumulated evidence has shown that these three gasotransmitters control ATP generation, mitochondrial biogenesis, glucose metabolism, insulin sensitivity, lipid metabolism, and thermogenesis, etc. Abnormal generation and metabolism of NO, H2S, and/or CO are involved in various abnormal metabolic diseases, including obesity, diabetes, and dyslipidemia. In this review, we summarized the roles of NO, H2S, and CO in the regulation of energy homeostasis as well as their involvements in the metabolism of dysfunction-related diseases. Understanding the interaction among these gasotransmitters and their specific molecular targets are very important for therapeutic applications.
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Affiliation(s)
- Amr Ali
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Canada.,Cardiovascular and Metabolic Research Unit, Laurentian University, Sudbury, Canada
| | - Yuehong Wang
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Canada.,Cardiovascular and Metabolic Research Unit, Laurentian University, Sudbury, Canada
| | - Lingyun Wu
- Cardiovascular and Metabolic Research Unit, Laurentian University, Sudbury, Canada.,School of Human Kinetics, Laurentian University, Sudbury, Canada.,Health Science North Research Institute, Sudbury, Canada
| | - Guangdong Yang
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Canada.,Cardiovascular and Metabolic Research Unit, Laurentian University, Sudbury, Canada
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Souza ALTD, Batalhão ME, Cárnio EC. Study of thermo-regulation as a worsening marker of experimental sepsis in an animal model. Rev Lat Am Enfermagem 2020; 28:e3290. [PMID: 32901764 PMCID: PMC7478883 DOI: 10.1590/1518-8345.3364.3290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 03/12/2020] [Indexed: 11/21/2022] Open
Abstract
Objective: to analyze variations in body temperature and in plasma nitrate and lactate concentrations in rats submitted to the experimental sepsis model. Method: a total of 40 rats divided equally into five groups. The induction of endotoxemia was performed with intravenous administration of lipopolysaccharide, 0.5 mg/Kg, 1.5 mg/Kg, 3.0 mg/Kg, and 10 mg/Kg, respectively. The control group received 0.5 mL of saline solution. The experiment lasted six hours, with evaluations performed at 0 (baseline data), 2nd, 4th, and 6thhours. Results: The animals that received doses up to 3.0 mg/kg showed a significant increase in body temperature compared to the group with 10 mg/kg, which showed a decrease in these values. The increase in plasma nitrate and lactate concentrations in the groups with lipopolysaccharide was significantly higher than in the group that received the saline solution and was correlated with the increase in body temperature. Conclusion: the variations in body temperature observed in this study showed the dose-dependent effect of lipopolysaccharide and were correlated with the increase in the concentrations of nitrate and plasma lactate biomarkers. The implications of this study are the importance of monitoring body temperature, together with the assessment of these pathophysiological markers, which suggest worsening in the prognosis of sepsis.
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Affiliation(s)
- André Luiz Thomaz de Souza
- Universidade de São Paulo, Escola de Enfermagem de Ribeirão Preto, PAHO/WHO Collaborating Centre at the Nursing Research Development, Ribeirão Preto, SP, Brazil.,Faculdades Integradas do Vale do Ribeira, Faculdade de Enfermagem, Registro, SP, Brazil
| | - Marcelo Eduardo Batalhão
- Universidade de São Paulo, Escola de Enfermagem de Ribeirão Preto, PAHO/WHO Collaborating Centre at the Nursing Research Development, Ribeirão Preto, SP, Brazil
| | - Evelin Capellari Cárnio
- Universidade de São Paulo, Escola de Enfermagem de Ribeirão Preto, PAHO/WHO Collaborating Centre at the Nursing Research Development, Ribeirão Preto, SP, Brazil
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5
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Abstract
Oral administration of l-citrulline (l-Cit) caused hypothermia, but l-Cit is not recommended in poultry diets in Japan. Watermelon is a natural source of l-Cit. The objective of this study is to examine the effect of watermelon waste, i.e., watermelon rind (WR) on the body temperature and plasma free amino acids of chicks. In Experiment 1, 14-day-old chicks were subjected to acute oral administration of WR extract (WRE) (2 ml) under control thermoneutral temperature (CT). In Experiment 2, 15-day-old chicks were orally administered 1.6 ml of either WRE, lowdose l-Cit (7.5 mmol/10 ml), or high-dose l-Cit (15 mmol/10 ml) under CT. In both experiments, rectal temperature (RT) and plasma free amino acids were analyzed. In Experiment 3, after dual oral administration of (1.6 ml) WRE or l-Cit (15 mmol/10 ml), 15-day-old chicks were exposed to high ambient temperature (HT; 35±1°C, 2 h) to monitor changes in RT. Acute oral administration of WRE significantly reduced RT under CT. The degree of RT reduction by WRE was similar to that by high l-Cit. Moreover, RT was significantly low at HT owing to the oral administration of WRE. However, the reduced RT was difficult to explain by the content of Cit in WRE alone. In conclusion, WRE could be used as a dietary ingredient to reduce body temperature for imparting thermotolerance in chicks.
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6
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N P, Ss A, Pv M. Comprehensive biology of antipyretic pathways. Cytokine 2019; 116:120-127. [PMID: 30711851 DOI: 10.1016/j.cyto.2019.01.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 01/09/2019] [Accepted: 01/11/2019] [Indexed: 01/10/2023]
Abstract
Pyrogens, the fever inducing substances accidently enter into a human body through contamination from medical or pharmaceutical products may create mild to severe complications including septicaemia and shocking syndromes. To avoid such drastic situations all the pharmaceuticals and medical devices are analysed for presence of pyrogens prior to their release into market. The entry of exogenous pyrogens like bacterial endotoxins induces the release of endogenous pyrogens or inflammatory cytokines that activate immune system to defend against these pathogens. Generation of heat is considered as one of the important defence mechanism of body achieved through receptor mediated interaction of endogenous pyrogens at the thermoregulatory centre of hypothalamus. However, uncontrolled fever and febrile reaction may cause lethal effects to the subject itself. So a well sophistically functioning antipyretic mechanism is necessary to achieve thermoregulation. The coordinated interaction of antipyretic cytokines and other mediators are active in human immune system which play a crucial role in maintaining thermal homeostasis. The multiple interacting antipyretic signals and their mechanism are the major subjects of this review.
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Affiliation(s)
- Prajitha N
- Toxicology Division, Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Poojapura, Trivandrum 695 012, Kerala, India
| | - Athira Ss
- Toxicology Division, Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Poojapura, Trivandrum 695 012, Kerala, India
| | - Mohanan Pv
- Toxicology Division, Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Poojapura, Trivandrum 695 012, Kerala, India.
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7
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Chowdhury VS, Han G, Bahry MA, Tran PV, Do PH, Yang H, Furuse M. L-Citrulline acts as potential hypothermic agent to afford thermotolerance in chicks. J Therm Biol 2017; 69:163-170. [DOI: 10.1016/j.jtherbio.2017.07.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Revised: 07/18/2017] [Accepted: 07/18/2017] [Indexed: 11/25/2022]
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8
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Laouafa S, Elliot-Portal E, Revollo S, Schneider Gasser EM, Joseph V, Voituron N, Gassmann M, Soliz J. Hypercapnic ventilatory response is decreased in a mouse model of excessive erythrocytosis. Am J Physiol Regul Integr Comp Physiol 2016; 311:R940-R947. [PMID: 27605561 DOI: 10.1152/ajpregu.00226.2016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 08/10/2016] [Indexed: 11/22/2022]
Abstract
The impact of cerebral erythropoietin (Epo) in the regulation of the hypercapnic ventilatory response (HcVR) is controversial. While we reported that cerebral Epo does not affect the central chemosensitivity in C57Bl6 mice receiving an intracisternal injection of sEpoR (the endogenous antagonist of Epo), a recent study in transgenic mice with constitutive high levels of human Epo in brain and circulation (Tg6) and in brain only (Tg21), showed that Epo blunts the HcVR, maybe by interacting with central and peripheral chemoreceptors. High Epo serum levels in Tg6 mice lead to excessive erythrocytosis (hematocrit ~80-90%), the main symptom of chronic mountain sickness (CMS). These latter results support the hypothesis that reduced central chemosensitivity accounts for the hypoventilation observed in CMS patients. To solve this intriguing divergence, we reevaluate HcVR in Tg6 and Tg21 mouse lines, by assessing the metabolic rate [O consumption (V̇) and CO production (V̇)], a key factor modulating ventilation, the effect of which was not considered in the previous study. Our results showed that the decreased HcVR observed in Tg6 mice (~70% reduction; < 0.01) was due to a significant decrease in the metabolism (~40%; < 0.0001) rather than Epo's effect on CO chemosensitivity. Additional analysis in Tg21 mice did not reveal differences of HcVR or metabolism. We concluded that cerebral Epo does not modulate the central chemosensitivity system, and that a metabolic effect upon CO inhalation is responsible for decreased HcVR observed in Tg6 animals. As CMS patients also show decreased HcVR, our findings might help to better understand respiratory disorders at high altitude.
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Affiliation(s)
- Sofien Laouafa
- Centre de Recherche du CHU de Québec, Pavillon St François d'Assise, Département de Pédiatrie, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Elizabeth Elliot-Portal
- Centre de Recherche du CHU de Québec, Pavillon St François d'Assise, Département de Pédiatrie, Faculté de Médecine, Université Laval, Québec, QC, Canada.,Molecular biology and Biotechnology Institute, Universidad Mayor de San Andres, La Paz, Bolivia
| | - Susana Revollo
- Centre de Recherche du CHU de Québec, Pavillon St François d'Assise, Département de Pédiatrie, Faculté de Médecine, Université Laval, Québec, QC, Canada.,Molecular biology and Biotechnology Institute, Universidad Mayor de San Andres, La Paz, Bolivia
| | - Edith M Schneider Gasser
- Institute of Veterinary Physiology, Vetsuisse Faculty, and Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland; and
| | - Vincent Joseph
- Centre de Recherche du CHU de Québec, Pavillon St François d'Assise, Département de Pédiatrie, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Nicolas Voituron
- Université Paris 13, Sorbonne Paris Cité, UFR SMBH, Laboratoire "Hypoxie et poumons," Bobigny, France
| | - Max Gassmann
- Institute of Veterinary Physiology, Vetsuisse Faculty, and Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland; and.,Universidad Peruana Cayetano Heredia (UPCH), Lima, Peru
| | - Jorge Soliz
- Centre de Recherche du CHU de Québec, Pavillon St François d'Assise, Département de Pédiatrie, Faculté de Médecine, Université Laval, Québec, QC, Canada;
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9
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Roth J, Blatteis CM. Mechanisms of fever production and lysis: lessons from experimental LPS fever. Compr Physiol 2015; 4:1563-604. [PMID: 25428854 DOI: 10.1002/cphy.c130033] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Fever is a cardinal symptom of infectious or inflammatory insults, but it can also arise from noninfectious causes. The fever-inducing agent that has been used most frequently in experimental studies designed to characterize the physiological, immunological and neuroendocrine processes and to identify the neuronal circuits that underlie the manifestation of the febrile response is lipopolysaccharide (LPS). Our knowledge of the mechanisms of fever production and lysis is largely based on this model. Fever is usually initiated in the periphery of the challenged host by the immediate activation of the innate immune system by LPS, specifically of the complement (C) cascade and Toll-like receptors. The first results in the immediate generation of the C component C5a and the subsequent rapid production of prostaglandin E2 (PGE2). The second, occurring after some delay, induces the further production of PGE2 by induction of its synthesizing enzymes and transcription and translation of proinflammatory cytokines. The Kupffer cells (Kc) of the liver seem to be essential for these initial processes. The subsequent transfer of the pyrogenic message from the periphery to the brain is achieved by neuronal and humoral mechanisms. These pathways subserve the genesis of early (neuronal signals) and late (humoral signals) phases of the characteristically biphasic febrile response to LPS. During the course of fever, counterinflammatory factors, "endogenous antipyretics," are elaborated peripherally and centrally to limit fever in strength and duration. The multiple interacting pro- and antipyretic signals and their mechanistic effects that underlie endotoxic fever are the subjects of this review.
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Affiliation(s)
- Joachim Roth
- Department of Veterinary Physiology and Biochemistry, Justus-Liebig-University, Giessen, Germany; Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee
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10
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Hypothermia attenuates NO production in anesthetized rats with endotoxemia. Naunyn Schmiedebergs Arch Pharmacol 2014; 387:659-65. [DOI: 10.1007/s00210-014-0977-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 03/24/2014] [Indexed: 02/04/2023]
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11
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Rawls SM, Benamar K. Effects of opioids, cannabinoids, and vanilloids on body temperature. Front Biosci (Schol Ed) 2011; 3:822-45. [PMID: 21622235 DOI: 10.2741/190] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Cannabinoid and opioid drugs produce marked changes in body temperature. Recent findings have extended our knowledge about the thermoregulatory effects of cannabinoids and opioids, particularly as related to delta opioid receptors, endogenous systems, and transient receptor potential (TRP) channels. Although delta opioid receptors were originally thought to play only a minor role in thermoregulation compared to mu and kappa opioid receptors, their activation has been shown to produce hypothermia in multiple species. Endogenous opioids and cannabinoids also regulate body temperature. Mu and kappa opioid receptors are thought to be in tonic balance, with mu and kappa receptor activation producing hyperthermia and hypothermia, respectively. A particularly intense research focus is TRP channels, where TRPV1 channel activation produces hypothermia whereas TRPA1 and TRPM8 channel activation causes hyperthermia. The marked hyperthermia produced by TRPV1 channel antagonists suggests these warm channels tonically control body temperature. A better understanding of the roles of cannabinoid, opioid, and TRP systems in thermoregulation may have broad clinical implications and provide insights into interactions among neurotransmitter systems involved in thermoregulation.
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Affiliation(s)
- Scott M Rawls
- Department of Pharmaceutical Sciences, Temple University Health Sciences Center, Temple University, Philadelphia, PA 19140, USA.
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12
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Rawls SM, Benamar K. Effects of opioids, cannabinoids, and vanilloids on body temperature. Front Biosci (Schol Ed) 2011. [PMID: 21622235 DOI: 10.2741/s190] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cannabinoid and opioid drugs produce marked changes in body temperature. Recent findings have extended our knowledge about the thermoregulatory effects of cannabinoids and opioids, particularly as related to delta opioid receptors, endogenous systems, and transient receptor potential (TRP) channels. Although delta opioid receptors were originally thought to play only a minor role in thermoregulation compared to mu and kappa opioid receptors, their activation has been shown to produce hypothermia in multiple species. Endogenous opioids and cannabinoids also regulate body temperature. Mu and kappa opioid receptors are thought to be in tonic balance, with mu and kappa receptor activation producing hyperthermia and hypothermia, respectively. A particularly intense research focus is TRP channels, where TRPV1 channel activation produces hypothermia whereas TRPA1 and TRPM8 channel activation causes hyperthermia. The marked hyperthermia produced by TRPV1 channel antagonists suggests these warm channels tonically control body temperature. A better understanding of the roles of cannabinoid, opioid, and TRP systems in thermoregulation may have broad clinical implications and provide insights into interactions among neurotransmitter systems involved in thermoregulation.
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Affiliation(s)
- Scott M Rawls
- Department of Pharmaceutical Sciences, Temple University Health Sciences Center, Temple University, Philadelphia, PA 19140, USA.
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13
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Chen F, Wang Y, Lee Cham J, Badoer E. Inhibition of nitric oxide synthase in the paraventricular nucleus prevents the hyperthermia-induced reduction of mesenteric blood flow in rats. Am J Physiol Regul Integr Comp Physiol 2010; 299:R596-602. [DOI: 10.1152/ajpregu.00003.2010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Increasing body core temperature reflexly decreases mesenteric blood flow (MBF), and the hypothalamic paraventricular nucleus (PVN) plays an essential role in this response. Nitric oxide (NO) is involved in temperature regulation and is concentrated within the PVN. The present study investigated whether NO in the PVN contributes to the cardiovascular responses elicited by hyperthermia. Anesthetized rats were microinjected bilaterally in the PVN (100 nl/side) with saline or NG-nitro-l-arginine methyl ester (l-NAME), a nitric oxide synthase inhibitor (100 or 200 nmol/100 nl) ( n = 5/group). Body core temperature was then elevated from 37°C to 39°C, and blood pressure (BP), heart rate (HR), MBF, and mesenteric vascular conductance (MVC) were monitored. In separate groups, l-NAME (200 nmol) ( n = 5) or saline ( n = 5) was microinjected in the PVN, but body core temperature was not elevated. In control rats, increasing body core temperature resulted in no marked change of BP but an increase in HR and significant decreases in MBF (15%) and MVC. Pretreatment with 100 nmol l-NAME did not affect the responses. In contrast, 200 nmol l-NAME prevented the normal reduction in MBF and MVC but did not significantly affect the BP and HR responses. In rats in which body core temperature was not increased, l-NAME reduced MBF by 19%. The present results suggest that endogenous NO in the PVN is important in mediating the reduction of MBF induced by hyperthermia. In the absence of hyperthermia, however, endogenous NO in the PVN may play a role in maintaining mesenteric vasodilation.
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Affiliation(s)
- Feng Chen
- School of Medical Sciences, Royal Melbourne Institute of Technology University, Melbourne, Victoria, Australia
| | - Yuliang Wang
- School of Medical Sciences, Royal Melbourne Institute of Technology University, Melbourne, Victoria, Australia
| | - Joo Lee Cham
- School of Medical Sciences, Royal Melbourne Institute of Technology University, Melbourne, Victoria, Australia
| | - Emilio Badoer
- School of Medical Sciences, Royal Melbourne Institute of Technology University, Melbourne, Victoria, Australia
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14
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Osaka T. Nitric oxide mediates noradrenaline-induced hypothermic responses and opposes prostaglandin E2-induced fever in the rostromedial preoptic area. Neuroscience 2009; 165:976-83. [PMID: 19896521 DOI: 10.1016/j.neuroscience.2009.10.069] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2009] [Revised: 10/22/2009] [Accepted: 10/31/2009] [Indexed: 11/20/2022]
Abstract
Noradrenaline (NA) microinjected into the rostromedial preoptic area (POA) elicits heat loss responses and opposes prostaglandin E(2)-induced fever. Here, I tested the hypothesis that local synthesis and release of nitric oxide (NO) mediates the NA-induced effects. The unilateral microinjection of the NO donor sodium nitroprusside (SNP, 8.4 nmol), but not that of saline solution, into the NA-sensitive site elicited an increase in tail skin temperature and decreases in the whole-body O(2) consumption rate, heart rate, and colonic temperature simultaneously in urethane-chloralose-anesthetized rats. Pretreatment with SNP greatly attenuated the thermogenic, tachycardic, and hyperthermic effects of prostaglandin E(2) (140 fmol) microinjected into the same site. Furthermore, the NA-induced hypothermic responses were largely blocked by a prior microinjection of an NO synthase inhibitor N(G)-monomethyl-L-arginine (L-NMMA, 5 nmol), but not by that of its inactive enantiomer, N(G)-monomethyl-D-arginine (D-NMMA, 5 nmol), at the same site. These results suggest that the hypothermic and antipyretic effects of NA are mediated by NO in the rostromedial POA.
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Affiliation(s)
- T Osaka
- Health Promotion and Exercise Program, National Institute of Health and Nutrition, 1-23-1 Toyama, Shinjuku 162-8636, Japan.
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15
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Nitric oxide donors in sepsis: a systematic review of clinical and in vivo preclinical data. Shock 2009; 30:653-9. [PMID: 18497711 DOI: 10.1097/shk.0b013e3181777eef] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
An abundant literature in the field of sepsis focuses on the role of NO. Inhibiting NO synthesis corrects certain hemodynamic parameters of septic shock but failed to improve outcome in patients. Conversely, administration of NO donors lowers blood pressure but restores microcirculatory flow in patients with sepsis. We undertook a systematic review of the literature to comprehensively summarize the results of studies exploring the effects of systemic NO donors in sepsis. We included both clinical and preclinical data. We described the details surrounding NO donor administration, and the results obtained in each study were regrouped in broad categories. In the case of animal research, we limited our data collection to in vivo protocols and described the sepsis model. Finally, we critically appraised all the studies included in the review. Overall, the reviewed publications aimed for physiopathological description rather than clinical relevance and did not meet the required criteria for extrapolation to clinical practice. With this reserve, NO donors usually improved the outcomes measured (e.g., mortality, pulmonary hypertension, tissue/organ perfusion, etc.) but also lowered blood pressure. We conclude that our findings warrant further animal experimentation designed to maximize clinical relevance.
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16
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Opioid, cannabinoid CB1 and NOP receptors do not mediate APAP-induced hypothermia in rats. Pharmacol Biochem Behav 2009; 92:503-7. [PMID: 19463266 DOI: 10.1016/j.pbb.2009.01.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Revised: 01/08/2009] [Accepted: 01/23/2009] [Indexed: 11/24/2022]
Abstract
Acetaminophen (APAP) produces antinociception and hypothermia. Because the antinociceptive effect in rats is partially dependent on opioid and cannabinoid CB1 receptor activation, we determined if activation of these receptors also contributes to the hypothermic effect of APAP. Rats injected with APAP (100, 250, 375 or 500 mg/kg, i.p.) displayed dose-related hypothermia. For combined administration, the hypothermic effect of APAP (400 mg/kg, i.p.) was not altered by pretreatment with: naltrexone (10 mg/kg, s.c.), a non-selective opioid antagonist; naltrindole (1 mg/kg, s.c.), a delta opioid antagonist; nor-binaltorphimine (10 mg/kg, i.p.), a kappa opioid antagonist; SR 141716A (3 mg/kg, i.m.), a cannabinoid CB1 receptor antagonist; or JTC-801(1 mg/kg, i.p.), a nociceptin/orphanin FQ peptide (NOP) receptor antagonist. The demonstration that APAP produces hypothermia independent of opioid, cannabinoid CB1 or NOP receptor activation is contrary to its antinociceptive effect, which requires opioid and cannabinoid CB1 receptor activation.
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Begg DP, Mathai ML, McKinley MJ, Frappell PB, Kent S. Central nitric oxide synthase inhibition restores behaviorally mediated lipopolysaccharide induced fever in near-term rats. Physiol Behav 2008; 94:630-4. [DOI: 10.1016/j.physbeh.2008.03.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2007] [Revised: 03/28/2008] [Accepted: 03/31/2008] [Indexed: 01/22/2023]
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Draisma A, Dorresteijn M, Pickkers P, van der Hoeven H. The effect of systemic iNOS inhibition during human endotoxemia on the development of tolerance to different TLR-stimuli. Innate Immun 2008; 14:153-9. [DOI: 10.1177/1753425908091959] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The phenomenon of repeated exposure to endotoxin resulting in diminished release of pro-inflammatory cytokines is called endotoxin tolerance, in which there is a putative role for nitric oxide (NO). We investigated the effect of selective inducible NO-synthase (iNOS) inhibition during experimental human endotoxemia on the development of tolerance to various Toll-like receptor (TLR) agonists ex vivo. Volunteers received 2 ng/kg Escherichia coli endotoxin in the absence ( n = 7) or presence ( n = 7) of the selective iNOS inhibitor aminoguanidine (bolus 5 mM followed by a continuous infusion of 1.5 mmol/h). At 0, 2 and 4 h, blood samples were drawn for ex vivo stimulation with different TLR agonists. Experimental endotoxemia did not induce tolerance to TLR-2 and TLR-7 stimulation. In TLR-3, TLR-4 and TLR-5 stimulated whole blood, pro- and anti-inflammatory cytokine release was attenuated at 4 h, indicating that endotoxin-induced tolerance is not confined to subsequent TLR-4 stimulation alone. Aminoguanidine-treated subjects also developed tolerance to TLR-4 stimulation. In contrast, tolerance to TLR-3 stimulation did not occur for IL-10, and tolerance in TLR-5 stimulated blood did not develop for both pro- and anti-inflammatory cytokines. The role of NO in the development of tolerance is different for the various TLRs stimulated and pro- and anti-inflammatory cytokines measured.
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Affiliation(s)
- Annelies Draisma
- Department of Intensive Care Medicine, Radboud University Nijmegen Medical Centre
| | - Mirrin Dorresteijn
- Department of Intensive Care Medicine, Radboud University Nijmegen Medical Centre
| | - Peter Pickkers
- Department of Intensive Care Medicine, Radboud University Nijmegen Medical Centre,
| | - Hans van der Hoeven
- Department of Intensive Care Medicine, Radboud University Nijmegen Medical Centre, Nijmegen University Centre for Infectious Diseases, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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Li S, Dou W, Tang Y, Goorha S, Ballou LR, Blatteis CM. Acetaminophen: antipyretic or hypothermic in mice? In either case, PGHS-1b (COX-3) is irrelevant. Prostaglandins Other Lipid Mediat 2008; 85:89-99. [PMID: 18083054 PMCID: PMC2329595 DOI: 10.1016/j.prostaglandins.2007.10.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 10/25/2007] [Accepted: 10/26/2007] [Indexed: 01/17/2023]
Abstract
Acetaminophen (AC) reduces the core temperatures (T(c)) of febrile and non-febrile mice alike. Evidence has been adduced that the selectively AC-sensitive PGHS isoform, PGHS-1b (COX-3), mediates these effects. PGHS-1b, however, has no catalytic potency in mice. To resolve this contradiction, AC was injected intravenously (i.v.) into conscious PGHS-1 gene-sufficient (wild-type (WT)) and -deficient (PGHS-1(-/-)) mice 60 min before or after pyrogen-free saline (PFS) or E. coli LPS (10 microg/kg) i.v. T(c) was monitored continuously; brain and plasma PGE(2) levels were determined hourly. AC at <160 mg/kg did not affect T(c) when given before PFS or LPS; at 160 mg/kg, it caused a approximately 2.5 degrees C T(c) fall in 60 min. LPS given after AC (all doses) induced a approximately 1 degrees C fever, not different from that in AC-untreated mice. But this rise was insufficient to overcome the hypothermia of the 160 mg/kg-treated mice; their T(c) culminated 1 degrees C below baseline. LPS given before AC similarly elevated T(c) approximately 1 degrees C. This rise was reduced to baseline in 30 min by 80 mg AC/kg; T(c) rebounded to its febrile level over the next 30 min. At 160 mg/kg, AC reduced T(c) to 4 degrees C below baseline in 60 min, where it remained until the end of the experiment. WT and PGHS-1(-/-) mice responded similarly to all the treatments. The basal brain and plasma PGE(2) levels of PFS mice and the elevated plasma levels of LPS mice were unchanged by AC at 160 mg/kg; but the latter's brain levels were reduced at 1h, then recovered. Thus, AC could exert an anti-PGHS-2 effect when this enzyme is upregulated in the brain of febrile mice. The hypothermia it induces in non-febrile mice, therefore, is due to another mechanism. PGHS-1b is not involved in either case.
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Affiliation(s)
- Shuxin Li
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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20
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Saia RS, Anselmo-Franci JA, Carnio EC. HYPOTHERMIA DURING ENDOTOXEMIC SHOCK IN FEMALE MICE LACKING INDUCIBLE NITRIC OXIDE SYNTHASE. Shock 2008; 29:119-26. [PMID: 17621253 DOI: 10.1097/shk.0b013e31805cdc96] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The present study was undertaken to evaluate: (1) whether lipopolysaccharide LPS-induced hypothermic responses may be altered during two estrous cycle phases, proestrus and diestrus, and after ovariectomy, followed by hormonal supplementation and (2) whether nitric oxide (NO) plays a role on LPS-induced hypothermia responses in female mice. Experiments were performed on adult female wild-type (WT) C57BL and inducible NO synthase knockout (KO) mice weighing 18 to 30 g. Endotoxemia was induced by intraperitoneal LPS administration from Escherichia coli at a nonlethal dose of 10 mg/kg, and body temperature was measured by biotelemetry. Hormonal replacement was performed in ovariectomized mice through 17beta-estradiol Silastic capsules (100 mug) and s.c. injection of progesterone (0.5 mg per animal). We observed that during the diestrus phase, mice presented more intensive hypothermia than during proestrus phase, and hormonal supplementation with 17beta-estradiol and progesterone attenuated hypothermia in ovariectomized mice. During diestrus and ovariectomy, KO mice had higher hypothermic response when compared with the WT group. During proestrus, the lack of statistical difference between KO and WT mice could be consequent of lower ovarian hormones plasma levels. After hormonal replacement, hypothermia was reverted in KO groups probably because of higher ovarian hormonal levels. In summary, the results demonstrated that NO release by inducible NO synthase has an important thermoregulatory role in LPS-induced hypothermia in female mice. Besides, this involvement is directly dependent on the presence of ovarian hormones and their respective levels.
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Affiliation(s)
- Rafael S Saia
- Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, São Paulo, Brazil
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21
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Gourine AV, Dale N, Llaudet E, Poputnikov DM, Spyer KM, Gourine VN. Release of ATP in the central nervous system during systemic inflammation: real-time measurement in the hypothalamus of conscious rabbits. J Physiol 2007; 585:305-16. [PMID: 17901122 PMCID: PMC2375460 DOI: 10.1113/jphysiol.2007.143933] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Receptors for extracellular ATP (both ionotropic and metabotropic) are widely expressed in the CNS both in neurones and glia. ATP can modulate neuronal activity in many parts of the brain and contributes to the central nervous control of several physiological functions. Here we show that during the systemic inflammatory response the extracellular concentrations of ATP increase in the anterior hypothalamus and this has a profound effect on the development of the thermoregulatory febrile response. In conscious rabbits we measured ATP release in real time with novel amperometric biosensors and monitored a marked increase in the concentration of ATP (4.0 ± 0.7 μm) in the anterior hypothalamus in response to intravenous injection of bacterial endotoxin – lipopolysaccharide (LPS). No ATP release was observed in the posterior hypothalamus. The release of ATP coincided with the development of the initial phase of the febrile response, starting 18 ± 2 min and reaching its peak 45 ± 2 min after LPS injection. Application of the ATP receptor antagonists pyridoxal-5′-phosphate-6-azophenyl-2′,4′-disulphonic acid, Brilliant Blue G or periodate oxidized ATP dialdehyde to the site of ATP release in the anterior hypothalamus markedly augmented and prolonged the febrile response. These data indicate that during the development of the systemic inflammation, ATP is released in the anterior hypothalamus to limit the magnitude and duration of fever. This release may also have a profound effect on the hypothalamic control of other physiological functions in which ATP and related purines have been implicated to play modulatory roles, such as food intake, hormone secretion, cardiovascular activity and sleep.
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Affiliation(s)
- Alexander V Gourine
- Department of Physiology, University College London, Gower Street, London WC1E 6BT, UK.
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Cham JL, Badoer E. Exposure to a hot environment can activate rostral ventrolateral medulla-projecting neurones in the hypothalamic paraventricular nucleus in conscious rats. Exp Physiol 2007; 93:64-74. [PMID: 17827254 DOI: 10.1113/expphysiol.2007.039560] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A major integrative site within the brain for autonomic function is the hypothalamic paraventricular nucleus (PVN). Several studies have suggested that the PVN may be involved in the responses regulating body temperature. Hyperthermia elicits redirection of blood flow from the viscera to the periphery and involves changes in sympathetic nerve activity mediated by the central nervous system. The hypothalamic PVN includes neurones that project to the rostral ventrolateral medulla (RVLM), an important autonomic region involved in the tonic regulation of sympathetic nerve activity. This pathway could contribute to the cardiovascular changes induced by hyperthermia. The PVN has a high concentration of nitrergic neurones and it is known that nitric oxide within the brain mediates heat dissipation. Thus the aims of this study were to determine whether RVLM-projecting neurones in the PVN are activated by heat and whether those neurones are also nitrergic. The results show that, compared with control conditions, exposure of conscious rats to a hot environment of 39 degrees C significantly increased the number of neurones containing a Fos-positive nucleus (a marker of activation) and significantly increased the number of activated RVLM-projecting neurones in the PVN. Also, although heating significantly increased the number of activated nitrergic PVN neurones, triple-labelled neurones (i.e. activated, nitrergic and RVLM projecting) in the PVN were rarely observed. The results suggest that RVLM-projecting neurones in the PVN may play a role in responses to heat exposure but these are not nitrergic.
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Affiliation(s)
- Joo Lee Cham
- School of Medical Sciences, RMIT University, PO Box 71, Bundoora 3083, Melbourne, Victoria, Australia
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Feleder C, Perlik V, Blatteis CM. Preoptic nitric oxide attenuates endotoxic fever in guinea pigs by inhibiting the POA release of norepinephrine. Am J Physiol Regul Integr Comp Physiol 2007; 293:R1144-51. [PMID: 17584955 DOI: 10.1152/ajpregu.00068.2007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Lipopolysaccharide (LPS) administration induces hypothalamic nitric oxide (NO); NO is antipyretic in the preoptic area (POA), but its mechanism of action is uncertain. LPS also stimulates the release of preoptic norepinephrine (NE), which mediates fever onset. Because NE upregulates NO synthases and NO induces cyclooxygenase (COX)-2-dependent PGE2, we investigated whether NO mediates the production of this central fever mediator. Conscious guinea pigs with intra-POA microdialysis probes received LPS intravenously (2 μg/kg) and, thereafter, an NO donor (SIN-1) or scavenger (carboxy-PTIO) intra-POA (20 μg/μl each, 2 μl/min, 6 h). Core temperature (Tc) was monitored constantly; dialysate NE and PGE2 were analyzed in 30-min collections. To verify the reported involvement of α2-adrenoceptors (AR) in PGE2 production, clonidine (α2-AR agonist, 2 μg/μl) was microdialyzed with and without SIN-1 or carboxy-PTIO. To assess the possible involvement of oxidative NE and/or NO products in the demonstrated initially COX-2-independent POA PGE2 increase, (+)-catechin (an antioxidant, 3 μg/μl) was microdialyzed, and POA PGE2, and Tc were determined. SIN-1 and carboxy-PTIO reduced and enhanced, respectively, the rises in NE, PGE2, and Tc produced by intravenous LPS. Similarly, they prevented and increased, respectively, the delayed elevations of PGE2 and Tc induced by intra-POA clonidine. (+)-Catechin prevented the LPS-induced elevation of PGE2, but not of Tc. We conclude that the antipyretic activity of NO derives from its inhibitory modulation of the LPS-induced release of POA NE. These data also implicate free radicals in POA PGE2 production and raise questions about its role as a central LPS fever mediator.
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Affiliation(s)
- Carlos Feleder
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, 894 Union Avenue, Memphis, TN 38163, USA
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24
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Begg DP, Kent S, McKinley MJ, Mathai ML. Suppression of endotoxin-induced fever in near-term pregnant rats is mediated by brain nitric oxide. Am J Physiol Regul Integr Comp Physiol 2007; 292:R2174-8. [PMID: 17332165 DOI: 10.1152/ajpregu.00032.2007] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Over the last three decades, experiments in several mammalian species have shown that the febrile response to bacterial endotoxin is attenuated late in pregnancy. More recent evidence has established that the expression of nitric oxide synthase (NOS) enzymes is increased in the brain late in pregnancy. The current study investigated the possible role of brain nitric oxide in mediating the phenomenon of fever suppression. Core body temperature (Tb) of near-term pregnant rats ( day 19 and 20) was measured following inhibition of brain NOS and intraperitoneal injection of LPS (50 μg/kg); they were compared with both day 15 pregnant and virgin animals. Intracerebroventricular injection with an inhibitor of NOS, NG-monomethyl-l-arginine citrate (l-NMMA; 280 μg), in near-term pregnant rats restored the febrile response to LPS. As expected, near-term dams that received intracerebroventricular vehicle + IP LPS did not increase Tb, in contrast to the 1.0 ± 0.2°C rise in Tb in dams treated with ICV l-NMMA + IP LPS ( P < 0.01). In virgin females and day 15 pregnant controls receiving this treatment, the increases in Tb were 1.5 ± 0.3°C and 1.6 ± 0.4°C, respectively. Thus, blockade of brain NOS restored the febrile response to LPS in near-term dams; at 5 h postinjection, Tb was 60–70% of that observed in virgins and day 15 pregnant animals. Intracerebroventricular l-NMMA alone did not induce a significant change in Tb in any group. These results suggest that the mechanism underlying the suppression of the febrile response in near-term pregnancy is mediated by nitric oxide signaling in the brain.
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Affiliation(s)
- Denovan P Begg
- School of Psychological Science, La Trobe University, Bundoora, Victoria, 3086 Australia.
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25
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Cham JL, Badoer E. Exposure to a hot environment can activate spinally projecting and nitrergic neurones in the lower brainstem in the rat. Exp Physiol 2007; 92:529-40. [PMID: 17329312 DOI: 10.1113/expphysiol.2006.036806] [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] [Indexed: 11/08/2022]
Abstract
Reflex responses to hyperthermia include sweating, salivation and a redirection of blood flow from the viscera to the periphery, and involve changes in peripheral nerve activity mediated by the central nervous system (CNS), including specific areas of the ventral lower brainstem. The lower brainstem contains nitrergic neurones and neurones that project to intermediolateral cell column; however, it is not known whether these populations of neurones in the lower brainstem are activated following hyperthermia. The aims of the present study were to determine whether lower brainstem neurones activated by acute hyperthermia are nitrergic and/or whether they also project to the spinal cord. Retrogradely transported rhodamine-tagged beads were microinjected into the spinal cord. The rats were heated (environmental temperature 39 degrees C) for 1 h. Following perfusion/fixation, brain sections were processed to detect Fos (a marker of neuronal activation) and NADPH-diaphorase activity (a marker of nitrergic neurones). The results showed a significant increase in activated neurones in the mid-line (by fivefold), ventromedial (by eightfold) and ventrolateral lower brainstem (by ninefold). Some of these neurones were nitrergic, particularly in the ventromedial lower brainstem (5% of the activated neurones in this region were nitrergic). A small proportion of activated neurones were spinally projecting neurones (2-3% of activated neurones were spinally projecting). There were no triple-labelled neurones at any level of the lower brainstem examined. These findings indicate that only a small proportion of nitrergic neurones and spinally projecting neurones are activated by hyperthermia.
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Affiliation(s)
- Joo Lee Cham
- School of Medical Sciences, RMIT University, PO Box 71, Bundoora 3083, Melbourne, Victoria, Australia
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26
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Saia RS, Carnio EC. Thermoregulatory role of inducible nitric oxide synthase in lipopolysaccharide-induced hypothermia. Life Sci 2006; 79:1473-8. [PMID: 16714035 DOI: 10.1016/j.lfs.2006.04.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2006] [Revised: 04/12/2006] [Accepted: 04/15/2006] [Indexed: 11/20/2022]
Abstract
We have tested the hypothesis that nitric oxide (NO) arising from inducible nitric oxide synthase (iNOS) plays a role in hypothermia during endotoxemia by regulating vasopressin (AVP) release. Wild-type (WT) and iNOS knockout mice (KO) were intraperitoneally injected with either saline or Escherichia coli lipopolysaccharide (LPS) 10.0 mg/kg in a final volume of 0.02 mL. Body temperature was measured continuously by biotelemetry during 24 h after injection. Three hours after LPS administration, we observed a significant drop in body temperature (hypothermic response) in WT mice, which remained until the seventh hour, returning then close to the basal level. In iNOS KO mice, we found a significant fall in body temperature after the fourth hour of LPS administration; however, the hypothermic response persisted until the end of the 24 h of the experiment. The pre-treatment with beta-mercapto-beta,beta-cyclopentamethylenepropionyl(1), O-Et-Tyr2, Val4, Arg8-Vasopressin, an AVP V1 receptor antagonist (10 microg/kg) administered intraperitoneally, abolished the persistent hypothermia induced by LPS in iNOS KO mice, suggesting the regulation of iNOS under the vasopressin release in this experimental model. In conclusion, our data suggest that the iNOS isoform plays a role in LPS-induced hypothermia, apparently through the regulation of AVP release.
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Affiliation(s)
- Rafael S Saia
- Departamento de Enfermagem Geral e Especializada, Escola de Enfermagem de Ribeirão Preto/USP, 14040-902- Ribeirão Preto, SP, Brazil
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27
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Endogenous antipyretics. Clin Chim Acta 2006; 371:13-24. [DOI: 10.1016/j.cca.2006.02.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Revised: 01/21/2006] [Accepted: 02/09/2006] [Indexed: 11/23/2022]
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Ravanelli MIB, Almeida MC, Branco LGS. Role of the locus coeruleus carbon monoxide pathway in endotoxin fever in rats. Pflugers Arch 2006; 453:471-6. [PMID: 16941138 DOI: 10.1007/s00424-006-0136-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2006] [Accepted: 07/04/2006] [Indexed: 11/25/2022]
Abstract
Carbon monoxide (CO) has been identified as a diffusible signaling messenger in the brain, capable of altering body temperature by stimulating soluble guanylate cyclase (sGC). However, its site of action remains unclear. Locus coeruleus (LC) is rich not only in sGC but also in heme oxygenase (HO; the enzyme that catalyses the metabolism of heme to CO, along with biliverdin and free iron). Therefore, the possible role of the HO-CO-cGMP pathway in the lipopolysaccharide (LPS)-induced fever regulation by LC neurones was investigated. Induction of the HO pathway using heme-lysinate (7.6 nmol, intra-LC) attenuated the febrile response, and this effect could be prevented by pretreatment with ODQ (an sGC inhibitor; given intracerebroventricularly, 1.3 nmol). Moreover, ZnDPBG (an HO inhibitor; 5 nmol, intra-LC) augmented the febrile response. Taken together, these data suggest that CO in the LC produced by the HO pathway and acting via cGMP plays an antipyretic role during LPS-fever in rats.
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Affiliation(s)
- Maria Ida Bonini Ravanelli
- Department of Physiology, Medical School of Ribeirão Preto, University of São Paulo, 14049-900, Ribeirão Preto, SP, Brazil
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29
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Jászberényi M, Bujdosó E, Bagosi Z, Telegdy G. Mediation of the behavioral, endocrine and thermoregulatory actions of ghrelin. Horm Behav 2006; 50:266-73. [PMID: 16643913 DOI: 10.1016/j.yhbeh.2006.03.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2005] [Revised: 03/17/2006] [Accepted: 03/20/2006] [Indexed: 10/24/2022]
Abstract
The action of ghrelin on telemetrically recorded motor activity and the transmission of the effects of this neuropeptide on spontaneous and exploratory motor activity and some related endocrine and homeostatic parameters were investigated. Different doses (0.5-5 microg) of ghrelin administered intracerebroventricularly caused significant increases in both square crossing and rearing activity in the "open-field" apparatus, while only the dose of 5 microg evoked a significant increase in the spontaneous locomotor activity recorded by telemetry. Ghrelin also induced significant increases in corticosterone release and core temperature. To determine the transmission of these neuroendocrine actions, the rats were pretreated with different antagonists, such as a corticotropin-releasing hormone (CRH) antagonist (alpha-helical CRH(9-41)), the nitric oxide synthase inhibitor Nomega-nitro-L-arginine-methyl ester (L-NAME), haloperidol, cyproheptadine or the cyclooxygenase inhibitor noraminophenazone (NAP). The open-field and biotelemetric observations revealed that the motor responses were diminished by pretreatment with the CRH antagonist and haloperidol. In the case of HPA (hypothalamic pituitary adrenal) activation, only cyproheptadine pretreatment proved effective; haloperidol and L-NAME did not modify the corticosterone response. NAP had only a transient, while cyproheptadine elicited a more permanent impact on the hyperthermic response evoked by ghrelin; the other antagonists proved to be ineffective. The present data suggest that both CRH release and dopaminergic transmission may be involved in the ghrelin-evoked behavioral responses. On the other hand, ghrelin appears to have an impact on the HPA response via a serotonergic pathway and on the hyperthermic response via a cyclooxygenase and a serotonergic pathway.
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Affiliation(s)
- M Jászberényi
- Department of Pathophysiology, University of Szeged, Neurohumoral Research Group, Hungarian Academy of Sciences, PO Box 427, Semmelweis u. 1, H-6701 Szeged, Hungary
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30
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Cham JL, Klein R, Owens NC, Mathai M, McKinley M, Badoer E. Activation of spinally projecting and nitrergic neurons in the PVN following heat exposure. Am J Physiol Regul Integr Comp Physiol 2006; 291:R91-101. [PMID: 16832907 DOI: 10.1152/ajpregu.00675.2005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study investigated the effect of acute thermal stimulation in conscious rats on the production of Fos, a marker of increased neuronal activity, in spinally projecting and nitrergic neurons in the hypothalamic paraventricular nucleus (PVN). The PVN contains a high concentration of nitrergic neurons, as well as neurons that project to the intermediolateral cell column (IML) of the spinal cord that can directly influence sympathetic nerve activity (SNA). During thermal stimulation, the PVN is activated, but it is unknown whether spinally projecting PVN neurons and the nitrergic neurons are involved. Compared with controls, rats exposed to an environmental temperature of 39 degrees C for 1 h had a 10-fold increase in the number of cells producing Fos in the PVN (133 +/- 23 vs. 1,336 +/- 43, respectively, P < 0.0001). Of the spinally projecting neurons in the PVN of heated rats (98 +/- 10), over 20% expressed Fos. Additionally, of the nitrergic neurons (NADPH-diaphorase positive) located in the parvocellular PVN (723 +/- 17), 40% also expressed Fos (P < 0.0001 compared with controls). Finally, there was a significant increase in the number of spinally projecting neurons in the PVN that were nitrergic and expressed Fos after heat exposure (12%) compared with controls (0.1%) (P < 0.0001). These results suggest that spinally projecting and nitrergic neurons in the PVN may contribute to the central pathways activated by thermal stimulation.
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Affiliation(s)
- Joo Lee Cham
- School of Medical Sciences, RMIT University, Victoria, Australia
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31
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Gray DA, Maloney SK, Kamerman PR. Lipopolysaccharide-induced fever in Pekin ducks is mediated by prostaglandins and nitric oxide and modulated by adrenocortical hormones. Am J Physiol Regul Integr Comp Physiol 2005; 289:R1258-64. [PMID: 16037125 DOI: 10.1152/ajpregu.00377.2005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Information on avian fever is limited, and, in particular, very little is known about the mediators and modulators of the febrile response in birds. Therefore, in this study, the possible mediatory roles of nitric oxide (NO) and prostaglandins (PGs), together with a potential modulatory role for adrenocortical hormones in the generation of fever was investigated in conscious Pekin ducks. Their body temperatures were continuously measured by abdominally implanted temperature-sensitive data loggers. The febrile response induced by intramuscular injection of LPS at a dose of 100 μg/kg was compared with and without inhibition of NO production by N-nitro-l-arginine methyl ester (l-NAME), inhibition of PG synthesis (by diclofenac), and elevation of circulating concentrations of dexamethasone and corticosterone (by exogenous administration). LPS administration induced a marked, monophasic fever with a rise in temperature of more than 1°C after 3–4 h. In the presence of l-NAME, diclofenac, and adrenocorticoids at doses that had no effect upon normal body temperature in afebrile ducks, there was a significant inhibition of the LPS-induced fever. In addition, during the febrile response, the blood concentration of corticosterone was significantly elevated (from a basal level of 73.6 ± 9.8 ng/ml to a peak level of 132.6 ± 16.5 ng/ml). The results strongly suggest that the synthesis of both NO and PGs is a vital step in the generation of fever in birds and that the magnitude of the response is subject to modulation by adrenocorticoids.
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Affiliation(s)
- David A Gray
- School of Physiology, University of the Witwatersrand, Medical School, 7 York Rd., Parktown 2193, Johannesburg, South Africa.
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Lacerda ACR, Marubayashi U, Coimbra CC. Nitric oxide pathway is an important modulator of heat loss in rats during exercise. Brain Res Bull 2005; 67:110-6. [PMID: 16140169 DOI: 10.1016/j.brainresbull.2005.06.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2005] [Accepted: 06/03/2005] [Indexed: 11/24/2022]
Abstract
To assess the role of nitric oxide (NO) in central thermoregulatory mechanisms during exercise, 1.43 micromol (2 microL) of N(omega)-nitro-L-arginine methyl ester (L-NAME, n=6), a NO synthase inhibitor, or 2 microL of 0.15M NaCl (SAL, n=6) was injected into the lateral cerebral ventricle of male Wistar rats immediately before the animals started running (18 m min(-1), 5% inclination). Core (Tb) and skin tail (Ttail) temperatures were measured. Body heating rate (BHR), threshold Tb for tail vasodilation (TTbV), and workload (W) were calculated. During the first 11 min of exercise, there was a greater increase in Tb in the L-NAME group than in the SAL group (BRH=0.17+/-0.02 degrees C min(-1), L-NAME, versus 0.09+/-0.01 degrees C min(-1), SAL, p<0.05). Following the first 11 min until approximately 40 min of exercise, Tb levels remained stable in both groups, but levels remained higher in the L-NAME group than in the SAL group (39.16+/-0.04 degrees C, L-NAME, versus 38.33+/-0.02 degrees C, SAL, p<0.01). However, exercise went on to induce an additional rise in Tb in the SAL group prior to fatigue. These results suggest that the reduced W observed in L-NAME-treated rats (10.8+/-2.0 kg m, L-NAME, versus 25.0+/-2.1 kg m, SAL, p<0.01) was related to the increased BHR in L-NAME-treated animals observed during the first 11 min of exercise (r=0.74, p<0.01) due to the change in TTbV (39.12+/-0.24 degrees C, L-NAME, versus 38.27+/-0.10 degrees C, SAL, p<0.05). Finally, our data suggest that the central nitric oxide pathway modulates mechanisms of heat dissipation during exercise through an inhibitory mechanism.
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Affiliation(s)
- Ana Cristina R Lacerda
- Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, 31270-901 Belo Horizonte, Minas Gerais, Brazil
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Ribeiro AC, Kapás L. Day- and nighttime injection of a nitric oxide synthase inhibitor elicits opposite sleep responses in rats. Am J Physiol Regul Integr Comp Physiol 2005; 289:R521-R531. [PMID: 15860646 DOI: 10.1152/ajpregu.00605.2004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous studies suggest that nitric oxide (NO) may play a role in sleep regulation, particularly in the homeostatic process. The present studies were undertaken to compare the sleep effects of injecting a NO synthase (NOS) inhibitor when homeostatic sleep pressure is naturally highest (light onset) or when it is at its nadir (dark onset) in rats. Sleep, electroencephalogram delta-wave activity during nonrapid eye movement sleep (NREMS), also known as slow-wave activity (SWA), and brain temperature responses to three doses of the NOS inhibitor Nω-nitro-l-arginine methyl ester (l-NAME; 5, 50, and 100 mg/kg) injected intraperitoneally at light or dark onset were examined in rats ( n = 6 to 8). The effects of 5 mg/kg l-NAME were determined in both normal and vagotomized (VX) rats. Light onset administration of 50 mg/kg l-NAME decreased NREMS amounts and suppressed SWA and increased rapid eye movement sleep (REMS) amounts. At dark onset, l-NAME injection also dose dependently suppressed SWA; however, unlike light onset injections, both NREMS and REMS amounts were increased after all three doses. Sleep responses to 5 mg/kg l-NAME were not different in control and VX rats, suggesting that the sleep effects of l-NAME are not mediated through the activation of sensory vagal mechanisms. The present findings suggest that timing of the injection is a major determinant of the sleep responses observed after systemic l-NAME injection in rats.
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Affiliation(s)
- Ana C Ribeiro
- Dept. of Biological Sciences, Fordham University, 441 E. Fordham Road, Bronx, NY 10458, USA
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Dias MB, Almeida MC, Carnio EC, Branco LGS. Role of nitric oxide in tolerance to lipopolysaccharide in mice. J Appl Physiol (1985) 2005; 98:1322-7. [PMID: 15579566 DOI: 10.1152/japplphysiol.01243.2004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The injection of repeated doses of lipopolysaccharide (LPS) results in attenuation of the febrile response, which is called endotoxin tolerance. We tested the hypothesis that nitric oxide (NO) arising from inducible NO synthase (iNOS) plays a role in endotoxin tolerance, using not only pharmacological trials but also genetically engineered mice. Body core temperature was measured by biotelemetry in mice treated with NG-monomethyl-l-arginine (l -NMMA, 40 mg/kg; a nonselective NO synthase inhibitor) or aminoguanidine (AG, 10 mg/kg; a selective iNOS inhibitor) and in mice deficient in the iNOS gene (iNOS KO) mice. Tolerance to LPS was induced by means of three consecutive LPS (100 μg/kg) intraperitoneal injections at 24-h intervals. In wild-type mice, we observed a significant reduction of the febrile response to repeated administration of LPS. Injection of l-NMMA and AG markedly enhanced the febrile response to LPS in tolerant animals. Conversely, iNOS-KO mice repeatedly injected with LPS did not become tolerant to the pyrogenic effect of LPS. These data are consistent with the notion that NO modulates LPS tolerance in mice and that iNOS isoform is involved in NO synthesis during LPS tolerance.
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Affiliation(s)
- Mirela B Dias
- Departamento de Morfologia, Estomatologia e Fisiologia, Faculdade de Odontologia de Ribeirão Preto, USP, 14040-904 Ribeirão Preto, SP, Brazil.
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Bhat AS, Tandan SK, Kumar D, Krishna V, Prakash VR. Interaction between inhibitors of inducible nitric oxide synthase and cyclooxygenase in Brewer's yeast induced pyrexia in mice: An isobolographic study. Eur J Pharmacol 2005; 511:137-42. [PMID: 15792781 DOI: 10.1016/j.ejphar.2005.01.048] [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: 08/19/2004] [Revised: 01/05/2005] [Accepted: 01/27/2005] [Indexed: 10/25/2022]
Abstract
We studied the interaction of S-methylisothiourea (a selective inducible nitric oxide synthase inhibitor) with rofecoxib (selective cyclooxygenase-2 inhibitor) and mefenamic acid (non-selective cyclooxygenase inhibitor) in Brewer's yeast-induced pyrexia in mice by isobolographic analysis. Each drug was effective in reducing pyrexia when used alone. Log-dose-response curves of all the three drugs did not show any significant departure from parallelism indicating thereby, a common mode of antipyretic action. However, rofecoxib exhibited significantly higher potency than S-methylisothiourea. Isobolographic analysis of combination of S-methylisothiourea with rofecoxib and mefenamic acid revealed additive interaction. Experimental ED(50) of the combinations was not significantly different from theoretical additive ED(50) of the corresponding drug combination, that substantiated the additive nature of interaction between inducible nitric oxide synthase and cyclooxygenase in Brewer's yeast-induced fever in mice. Results suggest involvement of a mediator that is subservient to both inducible nitric oxide synthase and cyclooxygenase-2 enzyme activities. For further investigation, peroxynitrite ion may be considered to be the putative mediator.
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Affiliation(s)
- Abdul-Shakoor Bhat
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, U.P. 243 122, India
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Mathai ML, Arnold I, Febbraio MA, McKinley MJ. Central blockade of nitric oxide synthesis induces hyperthermia that is prevented by indomethacin in rats. J Therm Biol 2004. [DOI: 10.1016/j.jtherbio.2004.08.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Gurin VN, Gurin AV, Melenchuk EV, Spyer KM. The effects of activation and blockade of central P2X receptors on body temperature. ACTA ACUST UNITED AC 2004; 33:845-51. [PMID: 14969421 DOI: 10.1023/a:1025967903081] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The aim of the present work was to identify the role of ATP acting on specific P2X receptors in the central mechanisms of thermoregulation. Immunohistochemical studies demonstrated that brainstem structures involved in controlling body temperature contained large number of nerve cells bearing P2X ATP receptors. Experiments on conscious rats involving intracerebroventricular administration of an ATP analog and P2X antagonists showed that both activation and blockade of central P2X receptors produced marked changes in body temperature. Analysis of the effects of these substances provided grounds for suggesting that ATP acting on P2X receptors fulfils an important function in the mechanisms of transmitting afferent information from peripheral thermal receptors to thermoregulatory centers in the brainstem with responsibility for heat loss, while in pyrogen-induced fever ATP acting on these receptors may be involved in the activity of the endogenous antipyretic system.
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Affiliation(s)
- V N Gurin
- Institute of Physiology, Belarus National Academy of Sciences, 28 Akademicheskaya Street, 220072 Minsk, Belarus
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Sanches DB, Carnio EC, Branco LGS. Central nNOS is involved in restraint stress-induced fever: evidence for a cGMP pathway. Physiol Behav 2003; 80:139-45. [PMID: 14568319 DOI: 10.1016/s0031-9384(03)00230-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
It has been shown that the NO pathway plays a major role in restraint stress-induced fever, and that the neuronal nitric oxide synthase (nNOS) seems to be the NOS isoform that accounts for the pyretic effect of NO in psychological stress-induced fever. However, no information exists as to localization of the nNOS, i.e., in the peripheral or in the central nervous system (CNS). Thus, in the present study, we tested the hypothesis that NO arising from nNOS in the CNS participates in restraint stress-induced fever. Moreover, we also assessed the involvement of cyclic guanosine monophosphate (cGMP) in the mediation of the NO effects. To this end, intracerebroventricular S-methyl-L-thiocitrulline (SMTC; a selective nNOS inhibitor), sodium nitroprusside (an NO donor) or Rp-guanosine 3',5'-cyclic monophosphothioate triethylamine (Rp-cGMPS; a specific membrane-permeable inhibitor of the activation by cGMP of cGMP-dependent protein kinase) were injected, and the colonic temperature (T(c)) of restrained or unrestrained rats was recorded. Both SMTC (0.5 mg/mul) and Rp-cGMPS (10 mug/mul) intracerebroventricular injections enhanced restraint fever, whereas intracerebroventricular injections of sodium nitroprusside (100 mug/mul) reduced this response. These data indicate that NO produced in the CNS, arising from nNOS and acting via cGMP, plays an antipyretic role in the restraint stress-induced fever.
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Affiliation(s)
- Daniela B Sanches
- Dentistry School of Ribeirão Preto and Nursing School of Ribeirão Preto, University of São Paulo, SP, Ribeirão Prêto, Brazil
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Rawls SM, Tallarida RJ, Gray AM, Geller EB, Adler MW. L-NAME (N omega-nitro-L-arginine methyl ester), a nitric-oxide synthase inhibitor, and WIN 55212-2 [4,5-dihydro-2-methyl-4(4-morpholinylmethyl)-1-(1-naphthalenyl-carbonyl)-6H-pyrrolo[3,2,1ij]quinolin-6-one], a cannabinoid agonist, interact to evoke synergistic hypothermia. J Pharmacol Exp Ther 2003; 308:780-6. [PMID: 14610231 DOI: 10.1124/jpet.103.054668] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cannabinoids evoke profound hypothermia in rats by activating central CB(1) receptors. Nitric oxide (NO), a prominent second messenger in central and peripheral neurons, also plays a crucial role in thermoregulation, with previous studies suggesting pyretic and antipyretic functions. Dense nitric-oxide synthase (NOS) staining and CB(1) receptor immunoreactivity have been detected in regions of the hypothalamus that regulate body temperature, suggesting that intimate NO-cannabinoid associations may exist in the central nervous system. The present study investigated the effect of N(omega)-nitro-L-arginine methyl ester (L-NAME), a NO synthase inhibitor, on the hypothermic response to WIN 55212-2 [4,5-dihydro-2-methyl-4(4-morpholinylmethyl)-1-(1-naphthalenylcarbonyl)-6H-pyrrolo[3,2,1ij]quinolin-6-one], a selective cannabinoid agonist, in rats. WIN 55212-2 (1-5 mg/kg, i.m.) produced dose-dependent hypothermia that peaked 45 to 90 min post-injection. L-NAME (10-100 mg/kg, i.m.) by itself did not significantly alter body temperature. However, a nonhypothermic dose of L-NAME (50 mg/kg) potentiated the hypothermia caused by WIN 55212-2 (0.5-5 mg/kg). The augmentation was strongly synergistic, indicated by a 2.5-fold increase in the relative potency of WIN 55212-2. The inactive enantiomer of WIN 55212-2, WIN 55212-3 [S-(-)-[2,3-dihydro-5-methyl-3-[(morpholinyl)methyl]pyrrolo[1,2,3-de]-1,4-benzoxazinyl]-(1-napthanlenyl) methanone mesylate] (5 mg/kg, i.m.), did not produce hypothermia in the absence or presence of L-NAME (50 mg/kg), confirming that cannabinoid receptors mediated the synergy. The present data are the first evidence that drug combinations of NOS blockers and cannabinoid agonists produce synergistic hypothermia. Thus, NO and cannabinoid systems may interact to induce superadditive hypothermia.
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Affiliation(s)
- S M Rawls
- Department of Pharmaceutical Sciences, Temple University School of Pharmacy, Philadelphia, PA 19140, USA.
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Giusti-Paiva A, Branco LGS, de Castro M, Antunes-Rodrigues J, Carnio EC. Role of nitric oxide in thermoregulation during septic shock: involvement of vasopressin. Pflugers Arch 2003; 447:175-80. [PMID: 14530975 DOI: 10.1007/s00424-003-1164-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2003] [Revised: 07/04/2003] [Accepted: 08/07/2003] [Indexed: 11/25/2022]
Abstract
We tested the hypothesis that the nitric oxide (NO) pathway in the central nervous system (CNS) plays a role in hypothermia, as well as in the febrile response during experimental septic shock, by regulating vasopressin (AVP) release. Experiments were performed on male Wistar rats treated with NG-nitro-L-arginine methyl ester (L-NAME), a non-selective NO synthase (NOS) inhibitor, injected intracerebroventricularly (250 microg/1 microl) 30 min before lipopolysaccharide (LPS) 1.5 mg/kg i.v. injection. One hour after LPS administration we observed a significant drop in body temperature (hypothermic response), followed by a temperature increase after the second hour (febrile response), which remained until the end of the experiment. Increased plasmatic AVP levels were concomitantly observed during hypothermia, nearly returning to basal levels during the febrile phase. When L-NAME was administered with LPS, plasmatic AVP concentrations remained high throughout the experiment, hypothermia was accentuated and the febrile response was abolished. Additionally, pre-treatment with beta-mercapto-beta,beta-cyclopentamethylenepropionyl1, O-Et-Tyr2, Val4, Arg8-vasopressin, an AVP V1 receptor blocker (10 microg/kg) administered i.v., reduced hypothermia and exacerbated the febrile response to endotoxin. In conclusion, our data indicate that the central NO pathway plays an inhibitory role in AVP release during experimental septic shock, which seems to be critical for the thermoregulation during this pathophysiological state.
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Affiliation(s)
- Alexandre Giusti-Paiva
- Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brasil
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Yao ST, Gourine AV, Spyer KM, Barden JA, Lawrence AJ. Localisation of p2x2 receptor subunit immunoreactivity on nitric oxide synthase expressing neurones in the brain stem and hypothalamus of the rat: a fluorescence immunohistochemical study. Neuroscience 2003; 121:411-9. [PMID: 14521999 DOI: 10.1016/s0306-4522(03)00435-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A large body of evidence suggests that nitric oxide (NO) and ATP act as neurotransmitters in the regulatory mechanisms concerning several autonomic functions at the level of both the hypothalamus and the brain stem. In the present study, we investigated whether neuronal NO synthase containing neurones also express P2X(2) receptor subunit of the ATP-gated ion channel via double-labelling fluorescence immunohistochemistry. Our data demonstrate that a high percentage of neuronal NO synthase-immunoreactive neurones are also P2X(2)-immunoreactive in the rostral ventrolateral medulla (98%) and supraoptic nucleus of the hypothalamus (92%). Significant numbers of neuronal NO synthase-immunoreactive neurones are also P2X(2)-immunoreactive in the subpostremal (48%) and commissural (65%) subdivisions of the nucleus tractus solitarius. In the caudal ventrolateral medulla and raphe obscurus, 96% and 89%, respectively, of neuronal NO synthase containing neurones also express P2X(2) receptor subunit. In contrast to the supraoptic nucleus, there was a lower percentage of co-localisation between NO synthase and P2X(2) receptor subunit in the paraventricular nucleus of the hypothalamus. In summary, this study demonstrates for the first time that there is a widespread co-localisation of neuronal NO synthase and P2X(2) receptor subunit in the hypothalamus and brain stem of the rat. Further studies are required to elucidate whether NO and ATP functionally interact within the hypothalamus and the brain stem.
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Affiliation(s)
- S T Yao
- Department of Pharmacology, Monash University, P.O. Box 13E, Clayton, Victoria 3800, Australia.
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Benamar K, Yondorf MZ, Kon D, Geller EB, Adler MW. Role of the nitric-oxide synthase isoforms during morphine-induced hyperthermia in rats. J Pharmacol Exp Ther 2003; 307:219-22. [PMID: 12954818 DOI: 10.1124/jpet.103.053181] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Recently, we demonstrated that the diffusible messenger molecule nitric oxide (NO) is involved in the hyperthermic response induced by morphine by using a nonselective nitric-oxide synthase inhibitor, N-nitro-L-arginine methyl ester. The present work extended these studies to include 7-nitroindazole (7-NI), an inhibitor specific for neuronal nitric-oxide synthase (nNOS), N(5)-(-iminoethyl)-L-ornithine (L-NIO), an inhibitor of endothelial NOS (eNOS), and aminoguanidine (AG), a potent inhibitor of inducible NOS (iNOS). A biotelemetry system was used in this study to measure the body temperature (Tb). A dose of 7-NI (5 or 10 mg/kg), which did not affect Tb by itself, blocked the hyperthermia induced by morphine in a dose-dependent manner (15 mg/kg i.p.). However, pretreatment with L-NIO (10-20 mg/kg) or with AG (50 mg/kg) failed to alter the hyperthermia induced by morphine. L-NIO (10-20 mg/kg) or AG (50 mg/kg) had no effect on Tb. These results suggest the involvement of nNOS in morphine-induced hyperthermia.
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Affiliation(s)
- Khalid Benamar
- Center for Substance Abuse Research, Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA 19140, USA.
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Kozak W, Kozak A. Genetic Models in Applied Physiology. Differential role of nitric oxide synthase isoforms in fever of different etiologies: studies using Nos gene-deficient mice. J Appl Physiol (1985) 2003; 94:2534-44. [PMID: 12562678 DOI: 10.1152/japplphysiol.01042.2002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Male C57BL/6J mice deficient in nitric oxide synthase (NOS) genes (knockout) and control (wild-type) mice were implanted intra-abdominally with battery-operated miniature biotelemeters (model VMFH MiniMitter, Sunriver, OR) to monitor changes in body temperature. Intravenous injection of lipopolysaccharide (LPS; 50 microg/kg) was used to trigger fever in response to systemic inflammation in mice. To induce a febrile response to localized inflammation, the mice were injected subcutaneously with pure turpentine oil (30 microl/animal) into the left hindlimb. Oral administration (gavage) of N(G)-monomethyl-l-arginine (l-NMMA) for 3 days (80 mg. kg(-1). day(-1) in corn oil) before injection of pyrogens was used to inhibit all three NOSs (N(G)-monomethyl-d-arginine acetate salt and corn oil were used as control). In normal male C57BL/6J mice, l-NMMA inhibited the LPS-induced fever by approximately 60%, whereas it augmented fever by approximately 65% in mice injected with turpentine. Challenging the respective NOS knockout mice with LPS and with l-NMMA revealed that inducible NOS and neuronal NOS isoforms are responsible for the induction of fever to LPS, whereas endothelial NOS (eNOS) is not involved. In contrast, none of the NOS isoforms appeared to trigger fever to turpentine. Inhibition of eNOS, however, exacerbates fever in mice treated with l-NMMA and turpentine, indicating that eNOS participates in the antipyretic mechanism. These data support the hypothesis that nitric oxide is a regulator of fever. Its action differs, however, depending on the pyrogen used and the NOS isoform.
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Affiliation(s)
- Wieslaw Kozak
- Department of Physiology, Medical College of Georgia, Augusta, Georgia 30912, USA.
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Almeida MC, Pelá IR, Branco LGS. Fever induced by platelet-derived growth factor, in contrast to fever induced by lipopolysaccharide, depends only on nitric oxide, but not on carbon monoxide pathway. Eur J Pharmacol 2003; 467:133-40. [PMID: 12706466 DOI: 10.1016/s0014-2999(03)01636-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Platelet-derived growth factor (PDGF) is a multifunctional protein which is known to induce a febrile response when injected intracerebroventricularly. The gaseous neurotransmitters, nitric oxide (NO) and carbon monoxide (CO), are both known to exert thermoregulatory effects and to participate in lipopolysaccharide-induced fever. In this study, we investigated the role of NO and CO in the febrile response to PDGF-BB in rats. Intracerebroventricular (i.c.v.) injection of PDGF-BB produced a dose-dependent increase in body temperature. This increase in body temperature induced by PDGF-BB was exacerbated by N(G)-nitro-L-arginine methyl ester (L-NAME-a nonselective NO synthase inhibitor) and S-methyl-L-thiocitrulline treatment [SMTC-a neuronal NOS (nNOS) selective inhibitor], but not by aminoguanidine treatment [an inducible NOS (iNOS) selective inhibitor]. Zinc deuteroporphyrin 2,4-bis glycol treatment (ZnDPBG-a nonselective heme oxygenase (HO) blocker) did not affect PDGF-BB fever. Our data indicate that the NO but not the CO pathway participates in PDGF-BB fever. Furthermore, our data show that nNOS is the NOS isoform responsible for NO synthesis in this response.
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Affiliation(s)
- Maria Camila Almeida
- Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, 14049-900, Ribeirão Preto, SP, Brazil
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Benamar K, Geller EB, Adler MW. Role of the nitric oxide pathway in kappa-opioid-induced hypothermia in rats. J Pharmacol Exp Ther 2002; 303:375-8. [PMID: 12235273 DOI: 10.1124/jpet.102.036269] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The effect of central and peripheral administration of a nitric oxide synthase inhibitor, N-nitro-L-arginine methyl ester (L-NAME), on the hypothermia induced by the selective kappa-opioid receptor agonist trans-(+/-)3,4-dichloro-N-methyl-N-(2-[1-pyrrolidinyl]-cyclohexyl)-benzeneacetamide methane sulfate (U50,488H) was studied in male Sprague-Dawley rats. In the first series of experiments, we examined the effect of subcutaneous (s.c.) administration of L-NAME on the hypothermia induced by s.c. injection of U50,488H. L-NAME, at a dose of 50 mg/kg s.c., had no influence on body temperature (Tb). Coadministration of L-NAME (50 mg/kg, s.c.) with U50,488H (10 mg/kg, s.c.) blocked the hypothermia induced by U50,488H. In the second series of experiments, we investigated the effect of intracerebroventricular (i.c.v.) administration of L-NAME on the hypothermia induced by s.c. injection of U50,488H. L-NAME itself, given i.c.v. at a dose of 1 mg/rat, did not evoke any change in Tb. Administration of L-NAME (1 mg/rat, i.c.v.) caused a significant suppression of U50,488H hypothermia. The results indicate that either central or peripheral nitric oxide synthesis is required for the production of hypothermia induced by U50,488H.
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MESH Headings
- 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer/administration & dosage
- 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer/pharmacology
- Analgesics, Non-Narcotic/administration & dosage
- Analgesics, Non-Narcotic/pharmacology
- Animals
- Body Temperature/drug effects
- Cerebral Ventricles/drug effects
- Cerebral Ventricles/physiopathology
- Hypothermia/physiopathology
- Injections, Intraventricular
- Male
- NG-Nitroarginine Methyl Ester/administration & dosage
- NG-Nitroarginine Methyl Ester/pharmacology
- Nitric Oxide/physiology
- Rats
- Rats, Sprague-Dawley
- Receptors, Opioid, kappa/physiology
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Affiliation(s)
- Khalid Benamar
- Center for Substance Abuse Research and Department of Pharmacology, Temple University School of Medicine, Philadelphia, Pennsylvania 19140, USA.
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Steiner AA, Antunes-Rodrigues J, McCann SM, Branco LGS. Antipyretic role of the NO-cGMP pathway in the anteroventral preoptic region of the rat brain. Am J Physiol Regul Integr Comp Physiol 2002; 282:R584-93. [PMID: 11792670 DOI: 10.1152/ajpregu.00391.2001] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We tested the hypothesis that nitric oxide (NO) acts in the anteroventral preoptic region (AVPO) modulating fever. To this end, body core temperature (T(c)) of rats was monitored by biotelemetry before and after pharmacological modulation of the NO pathway. Nitrite/nitrate and cGMP in the anteroventral third ventricular region (AV3V), where the AVPO is located, were also determined. Intra-AVPO microinjection of the NO synthase (NOS) inhibitor N(G)-monomethyl-L-arginine (L-NMMA, 12.5 microg) did not affect basal T(c), but it enhanced the early stage of lipopolysaccharide (LPS) fever, indicating that NO plays an antipyretic role in the AVPO. In agreement, intra-AVPO microinjection of the NO donor sodium nitroprusside (5 microg) reduced T(c). The antipyretic effect of NO seems to be mediated by cGMP because 1) NO has been shown to activate soluble guanylate cyclase, 2) intra-AVPO microinjection of 8-bromo-cGMP (8-BrcGMP) reduced T(c), and 3) the changes in AV3V levels of nitrite/nitrate and cGMP were similar in the course of fever. Additionally, we observed that nitrite/nitrate and cGMP levels decreased in the AV3V after, but not before, the onset of LPS fever, showing that the activity of the NO-cGMP pathway is reduced in the AV3V after intraperitoneal LPS, a mechanism that could contribute to the genesis and maintenance of fever. It was also observed that the efficacy of 8-BrcGMP in reducing T(c) in the AVPO is increased after LPS, emphasizing that the NO-cGMP pathway is antipyretic. This response could explain why intra-AVPO L-NMMA enhanced the early stage of LPS fever, even though the activity of the NO pathway before the onset of fever was unchanged. In summary, these data support an antipyretic role of the NO-cGMP pathway in the AVPO.
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Affiliation(s)
- Alexandre A Steiner
- Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, 14040 - 904 Ribeirão Preto, São Paulo, Brazil
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47
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Sanches DB, Steiner AA, Branco LGS. Involvement of neuronal nitric oxide synthase in restraint stress-induced fever in rats. Physiol Behav 2002; 75:261-6. [PMID: 11890976 DOI: 10.1016/s0031-9384(01)00657-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Nitric oxide (NO) has been shown to be an important modulator of the febrile response to pyrogens and to psychological stress. In the present study, we aimed to identify the nitric oxide synthase (NOS) isoform (neuronal or inducible, nNOS and iNOS, respectively) involved in restraint stress fever. Colonic temperature (Tc) was measured in unanesthetized rats before and after treatment with the more selective nNOS inhibitor 7-nitroindazole or with the selective iNOS inhibitor aminoguanidine (AG) under unrestrained or restrained conditions. Intraperitoneal injection of AG (25 or 50 mg/kg) did not affect restraint fever, indicating that iNOS is unlikely to be involved in restraint fever. On the other hand, intraperitoneal injection of 7-nitroindazole (25 mg/kg) significantly attenuated the rise in the Tc caused by restraint stress, whereas it caused no change in Tc of euthermic animals. These data show that NO produced by nNOS plays an important role in the genesis of restraint stress-induced fever.
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Affiliation(s)
- Daniela B Sanches
- Department of Morphology, Estomatology, and Physiology, Dental School of Ribeirão Preto, University of São Paulo, 14040 904 Ribeirão Preto, SP, Brazil
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Benamar K, Xin L, Geller EB, Adler MW. Effect of central and peripheral administration of a nitric oxide synthase inhibitor on morphine hyperthermia in rats. Brain Res 2001; 894:266-73. [PMID: 11251200 DOI: 10.1016/s0006-8993(01)02025-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The effect of central and peripheral administration of a nitric oxide synthase inhibitor, N-nitro-L-arginine methyl ester (L-NAME), on morphine hyperthermia was studied in male Sprague-Dawley rats. The first series of experiments examined the effect of subcutaneous (s.c.) administration of L-NAME on the hyperthermia induced by morphine given s.c. in doses of 4 and 15 mg/kg. L-NAME, at a s.c. dose of 50 mg/kg, per se, had no influence on body temperature (T(b)). Coadministration of L-NAME (50 mg/kg, s.c.) with the higher dose of morphine (15 mg/kg, s.c.) caused a significant suppression of morphine hyperthermia during the first 30 min and then produced hypothermia. In contrast, s.c. injection of L-NAME (50 mg/kg, s.c.) failed to alter the hyperthermic response induced by the lower dose of morphine (4 mg/kg). In the second series of experiments, we investigated the effect of intracerebroventricular (i.c.v.) administration of L-NAME on the hyperthermia induced by morphine given s.c. L-NAME, itself, given i.c.v. at a dose of 1 mg did not evoke any change in T(b). Intracerebroventricular administration of L-NAME (1 mg) blocked the hyperthermia induced by 15 mg/kg morphine during the first 30 min and induced a slight hypothermia but did not alter the hyperthermia induced by 4 mg/kg morphine. The results indicate that either central or peripheral NO synthesis is required for the production of hyperthermia induced by 15 mg/kg of morphine. However, NO synthesis does not seem to be involved in the hyperthermic process induced by 4 mg/kg of morphine.
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Affiliation(s)
- K Benamar
- Center for Substance Abuse Research and Department of Pharmacology, Temple University School of Medicine, , Philadelphia, PA 19140, USA.
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Azad SC, Marsicano G, Eberlein I, Putzke J, Zieglgänsberger W, Spanagel R, Lutz B. Differential role of the nitric oxide pathway on delta(9)-THC-induced central nervous system effects in the mouse. Eur J Neurosci 2001; 13:561-8. [PMID: 11168564 DOI: 10.1046/j.1460-9568.2001.01431.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study investigated whether the nitric oxide pathway was involved in the central effects of Delta(9)-tetrahydrocannabinol (Delta(9)-THC), the major psychoactive constituent of cannabis sativa. Body temperature, nociception and locomotion were measured in neuronal nitric oxide synthase (nNOS) knock-out (KO) mice and wild-type (WT) controls after intraperitoneal application of Delta(9)-THC. These Delta(9)-THC-induced effects are known to be mediated through the brain-type cannabinoid receptor 1 (CB1). Therefore, in situ hybridization (ISH) experiments were performed in the adult murine brain to determine possible changes in CB1 mRNA levels in nNOS-KO, compared with WT mice, and to reveal brain areas where CB1 and nNOS were coexpressed in the same neurons. We found that an intraperitoneal injection of 10 mg/kg Delta(9)-THC led to the same increase in the hot plate latencies in both genotypes, suggesting that Delta(9)-THC-mediated antinociception does not involve nNOS. In contrast, a significant Delta(9)-THC-induced decrease of body temperature and locomotor activity was only observed in WT, but not in nNOS-KO mice. ISH revealed significantly lower levels of CB1 mRNA in the ventromedial hypothalamus (VMH) and the caudate putamen (Cpu) of the nNOS-KO animals, compared with WT mice. Both areas are known to be among the regions involved in cannabinoid-induced thermoregulation and decrease of locomotion. A numerical evaluation of nNOS/CB1 coexpression showed that approximately half of the nNOS-positive cells in the dorsolateral Cpu also express low levels of CB1. ISH of adjacent serial sections with CB1 and nNOS, revealed expression of both transcripts in VMH, suggesting that numerous nNOS-positive cells of VMH coexpress CB1. Our findings indicate that the nitric oxide pathway is involved in some, but not all of the central effects of Delta(9)-THC.
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Affiliation(s)
- S C Azad
- Clinic for Anaesthesiology, Pain Treatment Unit, Ludwig-Maximilians-University, Munich, Germany.
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