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Uyanga VA, Zhao J, Wang X, Jiao H, Onagbesan OM, Lin H. Dietary L-citrulline influences body temperature and inflammatory responses during nitric oxide synthase inhibition and endotoxin challenge in chickens. Stress 2022; 25:74-86. [PMID: 34962227 DOI: 10.1080/10253890.2021.2023495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
Recent studies have revealed the role of L-citrulline (L-CIT) in thermoregulation, but very little is known about the mechanisms involved. In this study, nitric oxide synthase inhibition and endotoxin-induced fever were used to investigate the effects of L-CIT on body temperature and inflammatory responses. In experiment 1, NW-nitro-L-arginine methyl ester (L-NAME, 150 mg/kg BW), was i. p. injected into chicks fed with basal (CON) or L-CIT diets for 14 days. In experiment 2, Lipopolysaccharide (LPS, 2 mg/kg BW) was i. p. injected following 21d feeding with CON or L-CIT diets. In experiment 3, chickens were injected with either L-NAME, LPS, or L-NAME + LPS following 26 days feeding with CON or L-CIT diets. The rectal (RT), ear (ET), and core body temperature (CBT) of chickens were examined. Results showed that L-NAME effectively decreased the RT, ET, CBT, and plasma NO concentration. In contrast, LPS increased NO levels and initiated hyperthermia by increasing RT, ET, CBT, and PGE2 levels. L-CIT diet reduced the mean CBT in experiment 1 and diminished the NO level, PGE2 level, and mean RT in experiment 3. Co-administration of L-CIT + LPS upregulated IL-6 expression, whereas, LPS injection alone induced IL-10, IL-1β, and TLR4 gene expressions. Therefore, this study reveals that L-CIT-induced hypothermia was related to NO inhibition and a decrease in PGE2 concentration. Conversely, LPS induced hyperthermia was associated with an increase in both NO and PGE2 concentrations.
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Affiliation(s)
- Victoria Anthony Uyanga
- Department of Animal Science, College of Animal Science and Veterinary Medicine, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control, Shandong Agricultural University, Tai'an City, China
| | - Jingpeng Zhao
- Department of Animal Science, College of Animal Science and Veterinary Medicine, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control, Shandong Agricultural University, Tai'an City, China
| | - Xiaojuan Wang
- Department of Animal Science, College of Animal Science and Veterinary Medicine, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control, Shandong Agricultural University, Tai'an City, China
| | - Hongchao Jiao
- Department of Animal Science, College of Animal Science and Veterinary Medicine, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control, Shandong Agricultural University, Tai'an City, China
| | - Okanlawon M Onagbesan
- Department of Animal Physiology, Federal University of Agriculture, Abeokuta P.M.B, Nigeria
| | - Hai Lin
- Department of Animal Science, College of Animal Science and Veterinary Medicine, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control, Shandong Agricultural University, Tai'an City, China
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Castineiras D, Armitage L, Lamas LP, De Baere S, Croubels S, Pelligand L. Perioperative pharmacokinetics and pharmacodynamics of meloxicam in emus (Dromaius novaehollandiae) of different age groups using nonlinear mixed effect modelling. J Vet Pharmacol Ther 2020; 44:603-618. [PMID: 33141479 DOI: 10.1111/jvp.12923] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 09/08/2020] [Accepted: 10/07/2020] [Indexed: 01/19/2023]
Abstract
Meloxicam is a widely used nonsteroidal anti-inflammatory drug in avian species. However, variability in pharmacokinetic (PK) and pharmacodynamic (PD) parameters in birds warrants species-specific studies for dose and dosing interval optimization. We performed a perioperative PK study of meloxicam (0.5 mg/kg, intravenously) on emus of three different age groups: 3 chicks (5 weeks old, 3.5 kg), 4 juveniles (26 weeks old, 18.8 kg) and 6 adults (66 weeks old, 38.8 kg). A two-compartment population PK model including weight as a significant covariate on clearance and central volume of distribution (V1) best fitted the data. The typical values (20 kg bird) for clearance and V1 were 0.54 L/kg/h and 0.095 L/kg. Both parameters significantly decreased with increasing weight/age. Meloxicam potency and selectivity for COX-1 and COX-2 were measured in whole blood assays (TxB2 production endpoint). Meloxicam was partially selective in emus (IC50 COX-1:COX-2 = 9.1:1). At the current empirical dose (0.5 mg/kg/24 hr), plasma meloxicam concentration is above IC50 of COX-2 for only 2 hr. PK/PD predicted dose required for 80% COX-2 inhibition over 24 hr were 3.4, 1.4 and 0.95 L/kg/day in chicks, juveniles and adult emus, respectively. The safety, therapeutic efficacy and practicality of modifying the daily dose or dose interval should be considered for dose recommendations in emus.
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Affiliation(s)
- Diego Castineiras
- Department of Clinical Services and Sciences, Royal Veterinary College, London, UK
| | - Lucy Armitage
- Department of Clinical Services and Sciences, Royal Veterinary College, London, UK
| | - Luís Pardon Lamas
- Structure & Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
| | - Siegrid De Baere
- Department of Pharmacology, Toxicology and Biochemistry, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Siska Croubels
- Department of Pharmacology, Toxicology and Biochemistry, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Ludovic Pelligand
- Department of Clinical Services and Sciences, Royal Veterinary College, London, UK.,Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
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Mehaisen GMK, Eshak MG, El Sabry MI, Abass AO. Expression of Inflammatory and Cell Death Program Genes and Comet DNA Damage Assay Induced by Escherichia coli in Layer Hens. PLoS One 2016; 11:e0158314. [PMID: 27347679 PMCID: PMC4922552 DOI: 10.1371/journal.pone.0158314] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 06/14/2016] [Indexed: 11/21/2022] Open
Abstract
Modern methods of industrial poultry and egg production systems involve stressful practices that stimulate Escherichia coli (E. coli) activity causing endotoxic shock. This investigation was conducted to evaluate the expression of pro-inflammatory cytokines and cell death program genes and DNA damage induced by E. coli in the brain and liver tissues of laying hens. A total of two hundred and ten H&N brown layer hens with 20 week age, were used in this research. First, preliminary experiments were designed (60 hens in total) to establish the optimal exposure dose of E. coli and to determine the nearest time of notable response to be used in the remainder studies of this research. At 35-wk of age, 150 hens were randomly assigned into 2 groups with 3 replicates of 25 birds each; the first group was injected in the brachial wing vein with 107E. coli colony/hen, while the second group was injected with saline and served as a control. The body temperature and plasma corticosterone concentration were measured 3 hr after injection. Specimens of liver and brain were obtained from each group and the gene expression of p38 mitogen-activated protein kinase, interlukin-1β (IL-1β), tumor necrosis factor alpha (TNF-α), Bax, and caspase-3 genes were measured by quantitative real-time PCR. DNA damage in the brain and liver tissues were also measured by comet assay. Hens treated with E. coli showed significant (P<0.05) increase of body temperature and plasma corticosterone (42.6°C and 14.5 ng/ml, respectively) compared to the control group (41.1°C and 5.5 ng/ml, respectively). Additional remarkable over-inflammation gene expression of p38, IL-1β and TNF-α.genes were also detected in the brain (2.2-fold, 2.0-fold and 3.3-fold, respectively) and the liver (2.1-fold, 1.9-fold and 3.0-fold, respectively) tissues of the infected chickens. It is also important to note that hens injected with E. coli showed an increase in DNA damage in the brain and liver cells (P<0.05). These results were synchronized with activating cell death program since our data showed significant high expression of Bax gene by 2.8- and 2.7-fold and caspase-3 gene by 2.5- and 2.7-fold in the brain and liver tissues of infected chickens, respectively (P<0.05). In conclusion, the current study indicates that E. coli injection induces inflammatory physiological response and triggers cell death program in the brain and liver. Our results provide more understanding to endotoxic shock by E. coli in chickens at cellular level. Further studies are required to confirm if such responses are destructive or protective to set the means through which a chicken mounts a successful defense against avian pathogenic E. coli.
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Affiliation(s)
- Gamal M. K. Mehaisen
- Department of Animal Production, Faculty of Agriculture, Cairo University, Giza, Egypt
- * E-mail:
| | - Mariam G. Eshak
- Department of Cell Biology, National Research Centre, Giza, Egypt
| | - M. I. El Sabry
- Department of Animal Production, Faculty of Agriculture, Cairo University, Giza, Egypt
| | - Ahmed O. Abass
- Department of Animal Production, Faculty of Agriculture, Cairo University, Giza, Egypt
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Dantonio V, Batalhão ME, Fernandes MHMR, Komegae EN, Buqui GA, Lopes NP, Gargaglioni LH, Carnio ÉC, Steiner AA, Bícego KC. Nitric oxide and fever: immune-to-brain signaling vs. thermogenesis in chicks. Am J Physiol Regul Integr Comp Physiol 2016; 310:R896-905. [DOI: 10.1152/ajpregu.00453.2015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 03/14/2016] [Indexed: 12/18/2022]
Abstract
Nitric oxide (NO) plays a role in thermogenesis but does not mediate immune-to-brain febrigenic signaling in rats. There are suggestions of a different situation in birds, but the underlying evidence is not compelling. The present study was designed to clarify this matter in 5-day-old chicks challenged with a low or high dose of bacterial LPS. The lower LPS dose (2 μg/kg im) induced fever at 3–5 h postinjection, whereas 100 μg/kg im decreased core body temperature (Tc) (at 1 h) followed by fever (at 4 or 5 h). Plasma nitrate levels increased 4 h after LPS injection, but they were not correlated with the magnitude of fever. The NO synthase inhibitor ( NG-nitro-l-arginine methyl ester, l-NAME; 50 mg/kg im) attenuated the fever induced by either dose of LPS and enhanced the magnitude of the Tc reduction induced by the high dose in chicks at 31–32°C. These effects were associated with suppression of metabolic rate, at least in the case of the high LPS dose. Conversely, the effects of l-NAME on Tc disappeared in chicks maintained at 35–36°C, suggesting that febrigenic signaling was essentially unaffected. Accordingly, the LPS-induced rise in the brain level of PGE2 was not affected by l-NAME. Moreover, l-NAME augmented LPS-induced huddling, which is indicative of compensatory mechanisms to run fever in the face of attenuated thermogenesis. Therefore, as in rats, systemic inhibition of NO synthesis attenuates LPS-induced fever in chicks by affecting thermoeffector activity and not by interfering with immune-to-brain signaling. This may constitute a conserved effect of NO in endotherms.
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Affiliation(s)
- Valter Dantonio
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinarian Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
- National Institute of Science and Technology-Comparative Physiology (INCT-Fisiologia Comparada), Rio Claro, São Paulo, Brazil
| | - Marcelo E. Batalhão
- Nursing School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Marcia H. M. R. Fernandes
- Department of Animal Science, College of Agricultural and Veterinarian Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
| | - Evilin N. Komegae
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, São Paulo, Brazil; and
| | - Gabriela A. Buqui
- Department of Physics and Chemistry, Núcleo de Pesquisa em Produtos Naturais e Sintéticos, Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Norberto P. Lopes
- Department of Physics and Chemistry, Núcleo de Pesquisa em Produtos Naturais e Sintéticos, Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Luciane H. Gargaglioni
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinarian Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
- National Institute of Science and Technology-Comparative Physiology (INCT-Fisiologia Comparada), Rio Claro, São Paulo, Brazil
| | - Évelin C. Carnio
- Nursing School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Alexandre A. Steiner
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, São Paulo, Brazil; and
| | - Kênia C. Bícego
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinarian Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
- National Institute of Science and Technology-Comparative Physiology (INCT-Fisiologia Comparada), Rio Claro, São Paulo, Brazil
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5
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Lieboldt MA, Frahm J, Halle I, Görs S, Schrader L, Weigend S, Preisinger R, Metges CC, Breves G, Dänicke S. Metabolic and clinical response to Escherichia coli lipopolysaccharide in layer pullets of different genetic backgrounds supplied with graded dietary L-arginine. Poult Sci 2016; 95:595-611. [PMID: 26740139 DOI: 10.3382/ps/pev359] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 10/14/2015] [Indexed: 01/27/2023] Open
Affiliation(s)
- M A Lieboldt
- Institute of Animal Nutrition, Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, Braunschweig 38116, Germany
| | - J Frahm
- Institute of Animal Nutrition, Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, Braunschweig 38116, Germany
| | - I Halle
- Institute of Animal Nutrition, Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, Braunschweig 38116, Germany
| | - S Görs
- Institute of Nutritional Physiology "Oskar Kellner", Leibniz Institute for Farm Animal Biology, Dummerstorf 18196, Germany
| | - L Schrader
- Institute of Animal Welfare and Animal Husbandry, Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, Celle 29223, Germany
| | - S Weigend
- Institute of Farm Animal Genetics, Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, Neustadt-Mariensee 31535, Germany
| | | | - C C Metges
- Institute of Nutritional Physiology "Oskar Kellner", Leibniz Institute for Farm Animal Biology, Dummerstorf 18196, Germany
| | - G Breves
- Institute of Physiology, University of Veterinary Medicine, Hannover 30173, Germany
| | - S Dänicke
- Institute of Animal Nutrition, Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, Braunschweig 38116, Germany
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6
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Groves PJ, Sharpe SM, Cox JM. Response of layer and broiler strain chickens to parenteral administration of a live Salmonella Typhimurium vaccine. Poult Sci 2015; 94:1512-20. [PMID: 26009756 DOI: 10.3382/ps/pev127] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2015] [Indexed: 01/28/2023] Open
Abstract
Responses to the parenteral administration of a live aroA deletion Salmonella serovar Typhimurium vaccine given to three brown egg layer strains and two broiler strains were studied. Twenty-five birds of each strain were reared together in floor pens to 6 weeks of age and then moved as individual strains to new floor pens and injected with 10(8) colony forming units (CFU) per bird of the vaccine bacteria intramuscularly or subcutaneously, 10(6) CFU per bird subcutaneously, or phosphate buffered saline (PBS) subcutaneously as a vaccination control. Three birds of one layer strain were injected intramuscularly with 0.5mg/ bird S. Typhimurium lipopolysaccharide (LPS) to evaluate whether response was similar for vaccine and endotoxin. Birds were weighed, and rectal temperatures recorded at the time of injection, then observed over 24 hours. Rectal temperatures were measured and blood samples collected for serum IL-6 assay at 3 hours post injection (PI). At 12 hours PI blood samples were drawn for analyses for plasma phosphorus (P), glucose (Glu), cholesterol (Cho), aspartate transaminase (AST), total protein (Ptn) and creatinine kinase (CK). Blood was sampled 14 days PI and tested for serum antibody to S. Typhimurium. Vaccination resulted in significant seroconversion by 14 days PI in all strains compared to the controls. The three layer strains exhibited a clinical malaise, evident within 90 minutes of injection, lasting for 12 hours, with complete recovery by 24 hours PI. Only the 10(8) CFU dose given subcutaneously produced an increase in rectal temperature 3 hours PI. Vaccination had no effect on IL-6 or Ptn. All vaccine doses increased P and the higher dose by either route decreased Cho in all bird strains. The 10(8) vaccine dose increased Glu and intramuscular injection markedly elevated CK only in the layer strains. The response was not completely congruous with that to LPS alone. The results highlight the need for consideration of differences in response of bird strain when consideration is given to the parenteral administration of live Salmonella vaccines.
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Affiliation(s)
- Peter J Groves
- The University of Sydney, Poultry Research Foundation, Camden, NSW, Australia
| | - Sue M Sharpe
- Birling Avian Laboratories, Bringelly, NSW, Australia University of New South Wales Australia, Kensington, NSW, Australia
| | - Julian M Cox
- University of New South Wales Australia, Kensington, NSW, Australia
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7
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Liu L, Qin D, Wang X, Feng Y, Yang X, Yao J. Effect of immune stress on growth performance and energy metabolism in broiler chickens. FOOD AGR IMMUNOL 2014. [DOI: 10.1080/09540105.2014.882884] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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8
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A review of the physiology of fever in birds. J Comp Physiol B 2012; 183:297-312. [DOI: 10.1007/s00360-012-0718-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 10/05/2012] [Accepted: 10/22/2012] [Indexed: 01/26/2023]
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9
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Kwok AHY, Wang Y, Leung FC. Molecular characterization of prostaglandin F receptor (FP) and E receptor subtype 3 (EP3) in chickens. Gen Comp Endocrinol 2012; 179:88-98. [PMID: 22885557 DOI: 10.1016/j.ygcen.2012.07.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2011] [Revised: 07/18/2012] [Accepted: 07/25/2012] [Indexed: 11/22/2022]
Abstract
Prostaglandin E and F regulate diverse physiological functions including gastrointestinal motility, fever induction and reproduction. This multitude of biological effects is mediated via their four E receptor subtypes (EP(1), EP(2), EP(3) and EP(4)) and F receptor (FP), respectively. Majority of these studies was performed in mammalian species, while investigations on their roles were impeded by inadequate information on their receptors in avian species. In present study, full-length cDNAs of chicken EP(3) (cEP(3)) and two isoforms of FP - cFPa and cFPb - were cloned from adult hen ovary. The putative cEP(3) and cFPa share high amino acid sequence identity with their respective orthologs, while the predicted cFPb is a novel middle-truncated splice variant which lacks 107 amino acids between transmembrane domains 4 and 6. RT-PCR showed that cEP(3), cFPa and cFPb are widely expressed in adult tissues examined, including ovary and oviduct. Using a pGL3-CRE luciferase reporter system, cEP(3)-expressing DF1 cells inhibited forskolin-induced luciferase activity (EC(50): <1.9 pM) upon PGE(2) treatment, suggesting that cEP(3) may functionally couple to Gi protein. Upon PGF(2α) addition, cFPa was shown to potentially couple to intracellular Ca(2+)-signaling pathway by pGL3-NFAT-RE reporter assay (EC(50): 2.9 nM), while cFPb showed no response. Using a pGL4-SRE reporter system, both cEP(3) and cFPa exhibited potential MAPK activation by PGE(2) and PGF(2α) at EC(50) 0.34 and 13 nM, respectively. Molecular characterization of these receptors paved the road to the better understanding of PGE(2) and PGF(2α) roles in avian physiology and comparative endocrinology studies.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Chickens/genetics
- Chickens/metabolism
- Cloning, Molecular
- Conserved Sequence
- Molecular Sequence Data
- Phylogeny
- Protein Isoforms/chemistry
- Protein Isoforms/genetics
- Protein Isoforms/metabolism
- RNA, Messenger/metabolism
- Receptors, Prostaglandin/chemistry
- Receptors, Prostaglandin/genetics
- Receptors, Prostaglandin/metabolism
- Receptors, Prostaglandin E, EP3 Subtype/chemistry
- Receptors, Prostaglandin E, EP3 Subtype/genetics
- Receptors, Prostaglandin E, EP3 Subtype/metabolism
- Sequence Alignment
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Affiliation(s)
- Amy H Y Kwok
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
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10
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Vaccination and acute phase mediator production in chickens challenged with low pathogenic avian influenza virus; novel markers for vaccine efficacy? Vaccine 2012; 30:3097-105. [DOI: 10.1016/j.vaccine.2012.02.055] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Revised: 02/07/2012] [Accepted: 02/20/2012] [Indexed: 12/11/2022]
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11
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Marais M, Maloney SK, Gray DA. Brain IL-6- and PG-dependent actions of IL-1β and lipopolysaccharide in avian fever. Am J Physiol Regul Integr Comp Physiol 2011; 301:R791-800. [DOI: 10.1152/ajpregu.00136.2011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
There is no persuasive evidence of a correlation between proinflammatory cytokines and avian fever. In this study, for the first time, we use avian cytokines to investigate a role for proinflammatory cytokines in the central component of avian fever. IL-1β and IL-6 injected intracerebroventricularly into Pekin ducks ( n = 8) initiated robust fevers of equal magnitude and duration, although there was a significant difference in the latency to a febrile response. In addition, the IL-1β-induced fever could be abolished with an intracerebroventricular injection of antibodies to avian IL-6 or an oral administration of a PG synthesis inhibitor. Our findings indicate the following sequence of events within the central component of the avian febrile mechanism: IL-1β gives rise to bioactive IL-6, which stimulates an accelerated synthesis of PGs, and these PGs then adjust the sensitivity of warm-sensitive neurons in the avian brain stem to mediate fever. Yet PGE2 was not upregulated in the cerebrospinal fluid of ducks made febrile with LPS. We conclude that IL-1β and IL-6 may well mediate fever by instigating an accelerated synthesis of brain-derived PG, of a class other than PGE2, or that IL-6 serves as one of the terminal mediators of the avian febrile response.
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Affiliation(s)
- Manette Marais
- School of Physiology, Faculty of Health Science, University of the Witwatersrand, Johannesburg, South Africa; and
| | - Shane K. Maloney
- School of Physiology, Faculty of Health Science, University of the Witwatersrand, Johannesburg, South Africa; and
- Physiology, School of Biomedical, Biomolecular, and Chemical Sciences, University of Western Australia, Perth, Australia
| | - David A. Gray
- School of Physiology, Faculty of Health Science, University of the Witwatersrand, Johannesburg, South Africa; and
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12
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Marais M, Maloney SK, Gray DA. Ambient temperature modulates the magnitude of LPS-induced fevers in Pekin ducks. J Therm Biol 2011. [DOI: 10.1016/j.jtherbio.2010.12.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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13
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Baert K, Duchateau L, De Boever S, Cherlet M, De Backer P. Antipyretic effect of oral sodium salicylate after an intravenousE. coliLPS injection in broiler chickens. Br Poult Sci 2010; 46:137-43. [PMID: 15957432 DOI: 10.1080/0071660500065151] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
A study was set up to investigate the influence of sodium salicylate on fever and acute phase reaction after lipopolysaccharide (LPS) injection in broiler chickens. An acute phase reaction was provoked through the intravenous injection of Escherichia coli LPS. Four oral doses of sodium salicylate were tested. Apart from body temperature, other inflammation indices, such as plasma corticosterone and ceruloplasmin, serum thromboxane B2 and zinc concentrations were monitored. Intravenous LPS induced a fever of about 1 degree C. A dose-dependent attenuation of the fever response of the chickens in the salicylate treated groups was observed. LPS-injected chickens also showed elevated plasma corticosterone and ceruloplasmin, while serum thromboxane and zinc concentrations decreased. Except for thromboxane B2, no linear relationship with increasing salicylate dose could be shown for the other blood variables. These data confirm that sodium salicylate is an effective antipyretic agent after injection of LPS in chickens, if used at an appropriate dosage. No dose-related change could be found for the other inflammation indices.
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Affiliation(s)
- K Baert
- Department of Pharmacology, Pharmacy and Toxicology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
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14
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De BOEVER S, NEIRINCKX EA, MEYER E, De BAERE S, BEYAERT R, De BACKER P, CROUBELS S. Pharmacodynamics of tepoxalin, sodium-salicylate and ketoprofen in an intravenous lipopolysaccharide inflammation model in broiler chickens. J Vet Pharmacol Ther 2010; 33:564-72. [DOI: 10.1111/j.1365-2885.2010.01184.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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15
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Marais M, Gray DA. A role for natriuretic peptide in lipopolysaccharide-induced fever in Pekin ducks (Anas platyrhynchos): is natriuretic peptide an endogenous antipyretic in birds? J Comp Physiol B 2008; 179:125-32. [DOI: 10.1007/s00360-008-0295-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2008] [Revised: 07/29/2008] [Accepted: 08/02/2008] [Indexed: 11/29/2022]
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16
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De Boever S, Beyaert R, Vandemaele F, Baert K, Duchateau L, Goddeeris B, De Backer P, Croubels S. The influence of age and repeated lipopolysaccharide administration on body temperature and the concentration of interleukin-6 and IgM antibodies against lipopolysaccharide in broiler chickens. Avian Pathol 2008; 37:39-44. [DOI: 10.1080/03079450701784875] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- S. De Boever
- a Department of Pharmacology, Toxicology, Biochemistry and Organ Physiology, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium
| | - R. Beyaert
- b Department for Molecular Biomedical Research, VIB , Unit of Molecular Signal Transduction in Inflammation , Ghent , Belgium
- c Department of Molecular Biology , Ghent University , Ghent , Belgium
| | - F. Vandemaele
- d Department Biosystems, Laboratory of Livestock Physiology, Immunology and Genetics, Faculty of Bioscience Engineering, K.U. Leuven , Leuven , Belgium
| | - K. Baert
- a Department of Pharmacology, Toxicology, Biochemistry and Organ Physiology, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium
| | - L. Duchateau
- e Department of Physiology and Biometrics, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium
| | - B. Goddeeris
- d Department Biosystems, Laboratory of Livestock Physiology, Immunology and Genetics, Faculty of Bioscience Engineering, K.U. Leuven , Leuven , Belgium
| | - P. De Backer
- a Department of Pharmacology, Toxicology, Biochemistry and Organ Physiology, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium
| | - S. Croubels
- a Department of Pharmacology, Toxicology, Biochemistry and Organ Physiology, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium
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17
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Bicego KC, Barros RCH, Branco LGS. Physiology of temperature regulation: comparative aspects. Comp Biochem Physiol A Mol Integr Physiol 2006; 147:616-639. [PMID: 16950637 DOI: 10.1016/j.cbpa.2006.06.032] [Citation(s) in RCA: 156] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2005] [Revised: 05/28/2006] [Accepted: 06/16/2006] [Indexed: 10/24/2022]
Abstract
Few environmental factors have a larger influence on animal energetics than temperature, a fact that makes thermoregulation a very important process for survival. In general, endothermic species, i.e., mammals and birds, maintain a constant body temperature (Tb) in fluctuating environmental temperatures using autonomic and behavioural mechanisms. Most of the knowledge on thermoregulatory physiology has emerged from studies using mammalian species, particularly rats. However, studies with all vertebrate groups are essential for a more complete understanding of the mechanisms involved in the regulation of Tb. Ectothermic vertebrates-fish, amphibians and reptiles-thermoregulate essentially by behavioural mechanisms. With few exceptions, both endotherms and ectotherms develop fever (a regulated increase in Tb) in response to exogenous pyrogens, and regulated hypothermia (anapyrexia) in response to hypoxia. This review focuses on the mechanisms, particularly neuromediators and regions in the central nervous system, involved in thermoregulation in vertebrates, in conditions of euthermia, fever and anapyrexia.
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Affiliation(s)
- Kênia C Bicego
- Department of Animal Physiology and Morfology, College of Agricultural and Veterinarian Sciences, Sao Paulo State University, Jaboticabal, São Paulo, Brazil.
| | - Renata C H Barros
- Department of General and Specialized Nursing, Nursing School of Ribeirão Preto, University of São Paulo, 14040-904, Ribeirão Preto, São Paulo, Brazil
| | - Luiz G S Branco
- Department of Morphology, Estomatology and Physiology, Dental School of Ribeirão Preto, University of São Paulo, 14040-904, Ribeirão Preto, São Paulo, Brazil
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18
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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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19
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Schrott LM, Sparber SB. Suppressed fever and hypersensitivity responses in chicks prenatally exposed to opiates. Brain Behav Immun 2004; 18:515-25. [PMID: 15331122 DOI: 10.1016/j.bbi.2003.12.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2003] [Revised: 12/09/2003] [Accepted: 12/11/2003] [Indexed: 10/26/2022] Open
Abstract
We have established procedures to reliably induce opiate dependence in the chick embryo via in ovo injection, early in embryonic development, of the long-acting and potent opiate N-desmethyl-l-alpha-noracetylmethadol (NLAAM). Prior studies found that there is continual exposure to NLAAM throughout embryogenesis and shortly after hatching there are signs of spontaneous withdrawal. In the present study, we used three doses of NLAAM (2.5, 5, and 10 mg/kg egg weight) to determine if prenatal opiate exposure followed by postnatal withdrawal interfered with appropriate neural-endocrine-immune interactions in the young chick. To ensure that effects were not a consequence of inappropriately large doses, we first examined acute and chronic toxicity and additional characteristics of postnatal opiate withdrawal. We then measured the corticosterone and fever responses to LPS stimulation during the withdrawal period. After the conclusion of opiate withdrawal, we assessed the hypersensitivity response to phytohemagglutinin (PHA). The fever response to LPS and the hypersensitivity response to PHA were suppressed by prenatal opiate exposure and postnatal withdrawal. The corticosterone response to LPS was not affected, but there were exaggerated corticosterone responses to saline injection in chicks exposed in ovo to NLAAM. It was unlikely that the effects of prenatal NLAAM were the result of toxicity, as little chronic toxicity was seen with the lower two doses of NLAAM, doses that yielded significant suppressions of neural-endocrine-immune responses. However, effects found in the chicks treated with 10 mg NLAAM/kg may have been partly related to the greater toxicity and/or protracted postnatal withdrawal in this group.
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Affiliation(s)
- Lisa M Schrott
- Department of Pharmacology and Therapeutics, Louisiana State University Health Sciences Center, 1501 Kings Highway, P.O. Box 33932, Shreveport, LA 71130-3932, USA.
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21
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Abstract
Intravenous (i.v.) injection of 10 microg/kg Escherichia coli lipopolysaccharide (LPS), applied at 13:00, evoked in pigeons a biphasic rise of core temperature (T(core)), so that LPS induced with a latency of 30 min first a decrease of T(core), and 90 min after LPS, T(core) increased, obtaining maximum values from 18:00 to 20:00. Prostaglandins have been considered to be importantly involved in fevers in mammals. To investigate an involvement of prostaglandins in the cyclic variations of T(core) in birds, pigeons were injected i.v. with either 10 mg/kg indomethacin (INDO) or 100 mg/kg aspirin, or they were treated with intracerebroventricular (i.c.v.) injections of 100 microg/kg INDO at various times before or after LPS. When INDO or aspirin was i.v. injected 30 or 15 min before LPS, it diminished the initial decrease of T(core) by more than 50%, whereas the i.v. injection of these drugs 2 and 4 h after LPS did not affect the febrile rise of T(core). i.c.v. injections of INDO given either before or after LPS neither influenced the initial drop of T(core) nor the following febrile hyperthermia. Both the i.v. injection of 1 mg/kg prostaglandin E(2) (PGE(2)) and the i.c.v. injection of 1 microg/kg PGE(2) lowered T(core). Our observations suggest that prostaglandins are not involved in the febrile elevation of T(core) in pigeons, but appear to participate in the decrease of T(core), which shortly follows the i.v. injection of LPS. This initial drop of T(core) following LPS may be caused by a peripheral action of prostaglandins because it was not influenced by the i.c.v. injection of indomethacin.
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Affiliation(s)
- Shigeki Nomoto
- Motor and Autonomic Nervous System Integration Research Group, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, 173-0015 Japan.
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22
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Leshchinsky TV, Klasing KC. Divergence of the inflammatory response in two types of chickens. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2001; 25:629-638. [PMID: 11472784 DOI: 10.1016/s0145-305x(01)00023-4] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We compared inflammatory responses to lipopolysaccharide (LPS) injection in laying type (Brown Nick) to broiler type (Avian x Avian) chicks. Rectal temperature was measured at 0, 1, 2, 4, 6, 12, and 24h after LPS injection (0, 0.1, 0.3, 0.6, 1, 2.5, or 5mg/kg bw). In layers, rectal temperature increased from 41.31+/-0.19 degrees C to a maximum 42.27+/-0.41 degrees C at 4h after 1mg/kg LPS. Relative to layers, the febrile response in broilers was considerably lower, delayed in onset, and required higher levels of LPS (5mg/kg). Proliferation of spleen cells from un-injected chicks in response to LPS, PHA, and Con A was evaluated in vitro. IFNgamma, TGFbeta(2), MGF and IL-1beta relative to beta-actin mRNA expression were analyzed in spleen cells stimulated with LPS. Splenocytes from layers had a higher proliferative response to LPS (P=0.045), but lower proliferative response to PHA (P=0.004) and Con A (P=0.004) than broilers. Expression of mRNA for MGF, IL-1beta and IFNgamma was lower in broilers than in layers (P<0.001). Reduced production of the pro-inflammatory cytokines in broilers could have resulted from the observed increased production of the immunosuppressive cytokine TGFbeta(2.) These differences in cytokine expression may explain the blunted febrile response in broilers compared to layers. Because the acute phase response of inflammation causes decreased food intake, the blunted inflammatory response of broilers may permit faster growth.
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Affiliation(s)
- T V Leshchinsky
- Department of Animal Science, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
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Gray DA, Maloney SK. Antidiuretic hormone and angiotensin II plasma concentrations in febrile Pekin ducks. J Physiol 1998; 511 ( Pt 2):605-10. [PMID: 9706035 PMCID: PMC2231132 DOI: 10.1111/j.1469-7793.1998.605bh.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/1998] [Accepted: 06/03/1998] [Indexed: 11/30/2022] Open
Abstract
1. The objective of this study was to determine the changes in plasma concentrations of the hormones arginine vasotocin (AVT) and angiotensin II (AII) associated with lipopolysaccharide (LPS)-induced fever in Pekin ducks. 2. LPS, intravenously administered into conscious birds at doses of 1, 10 and 100 microgram kg-1, caused dose-dependent and monophasic increases in body temperature, with fever index values of 3.5, 7.0 and 10.6, respectively. 3. Plasma AVT concentrations also increased with the progression of the fever, with the largest elevation (from 8.4 +/- 1. 6 to 25.2 +/- 3.2 pg ml-1; means +/- s.e.m., n = 7) being caused by the highest dose of LPS. 4. Plasma AII concentrations did not significantly change from basal values (mean of 45.5 +/- 6.3 pg ml-1 for all groups) during the acute phase of the fever response. 5. The osmotic status of the birds, as indicated by plasma osmolality and electrolyte values, did not significantly change in any of the experimental animals. 6. The elevation of AVT in avian fever leads to speculation about a possible antipyretic action of this hormone, which would have particular relevance to understanding the evolution of fever.
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Affiliation(s)
- D A Gray
- Department of Physiology, University of the Witwatersrand, Johannesburg 2193, South Africa
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Fraifeld V, Kaplanski J. Brain eicosanoids and LPS fever: species and age differences. PROGRESS IN BRAIN RESEARCH 1998; 115:141-57. [PMID: 9632934 DOI: 10.1016/s0079-6123(08)62034-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The results of the present study, summarized in Table 2, demonstrate that different species and strains of rodents (rats and mice) and birds (chickens) exhibit rather specific fever response. Systemic administration of LPS caused monophasic elevation in Tb of chickens, biphasic changes in Tb of rats (initial drop followed by an increase in Tb), whereas mice failed to develop hyperthermia and responded by a decreased Tb. The LPS-induced alterations in hypothalamic prostanoid synthesis were also rather species-specific and differ markedly even between the two strains of mice. We failed to find a common direct correlation between LPS-induced changes in Tb and hypothalamic prostanoid production in rodents (rats and mice). This observation is supported by our recent study on age-related changes in fever response in rats, where we found that hypothalami of LPS-treated old and young adult rats produced similar amounts of PGE2 and PGI2, in spite of more pronounced and prolonged hypothermia, and a delayed elevation in Tb of old rats, as compared with young (Fraifeld et al., 1995b). Moreover, the hypothalamus of febrile chickens did not display any detectable activation of PGE2 production, suggesting that PGE2 is not a common central mediator of fever in homeotherms (Fraifeld et al., 1995a). Apparently, the actual body temperature not always reflects the functional state of central thermostat, and increased PGE2 production in hypothalamus would not directly, at least in rodents, lead to body temperature elevation. Furthermore, peripheral effects, including PG-mediated ones, of pyrogens can interfere and even overcome their centrally-mediated effects (Morimoto et al., 1991; Burysek et al., 1993). Previously, we have shown that no additional elevation in hypothalamic PGE2 production occurs in response to doses of LPS over 10 micrograms in rats and 25 micrograms in mice, while the increased doses led to further changes in Tb response (Kaplanski et al., 1993). Morimoto et al. (1991) have considered that PGE2 acts centrally to cause fever and peripherally to cause hypothermia, and, hence, these opposing actions, both being induced by LPS, may act together to determine the final thermoregulatory response. Other possibilities could be related to counterbalance of endogenous antipyretics (Kluger, 1991; Kozak et al., 1995), that may occur not only at the level of thermoregulatory center but also outside the CNS (Klir et al., 1995), and to the existence of PG-independent mechanisms of LPS fever. The latter have been shown for IL-8 (Rothwell et al., 1990; Zampronio et al., 1994) and MIP-1 (Davatelis et al., 1989; Minano et al., 1990; Hayashi et al., 1995; Lopez-Valpuesta and Myers, 1995), which are, apparently, mediated via CRF (Strijbos et al., 1992; Zampronio et al., 1994), and INF-alpha, mediated via the opioid receptor mechanisms (Hori et al., 1991, 1992). However, it has been shown recently that in different species the same pyrogenic cytokines (IL-8) may induced fever via different, PG-independent (in rats; Zampronio et al., 1994) or PG-dependent (in rabbits; Zampronio et al., 1995) mechanisms. It should be noted that fever response is not always accompanied by an elevation in Tb. The final effect of pyrogens on body temperature depends upon the balance between heat production and heat loss, which in turn is highly dependent upon body size and ambient temperature, especially in small animals. Perhaps, the hypothermic response observed in our mice and rats at 22 degrees C may be in part attributed to ambient temperature, which was below a thermoneutral zone. The reduced febrile response is considered, at least in part, to contribute to an increased mortality and prolonged recovery from infections (Kluger, 1986). From this point, it is difficult to suggest whether the hypothermia observed in our mice and rats could be of somewhat adaptive significance. It has been shown that at the ambient temperature of 30 degrees C, Swiss Webster mice can re
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Affiliation(s)
- V Fraifeld
- Department of Clinical Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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25
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Chemo A, Fraifeld V, Adramovich L, Sod-Moriah UA, Kaplanski J. Tolerance to lipopolysaccharide is not related to the ability of the hypothalamus to produce prostaglandin E2. Life Sci 1997; 61:813-8. [PMID: 9275011 DOI: 10.1016/s0024-3205(97)00563-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The effects of repeated administration of Escherichia coli lipopolysaccharide (LPS) on body temperature and hypothalamic prostaglandin E2 (PGE2) production was examined in male Sprague-Dawley rats to elucidate whether the development of endotoxin tolerance is related to the ability of the hypothalamus to produce PGE2. Initial injection of LPS resulted in hyperthermia, preceded by short-termed hypothermia, while no changes in body temperature were observed after the second injection (administered 48 h later). In contrast, LPS induced elevation in hypothalamic PGE2 production after both the first and second injections of the pyrogen. This led us to conclude that endotoxin tolerance is independent of the hypothalamic production of PGE2 in response to repeated administration of LPS.
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Affiliation(s)
- A Chemo
- Department of Clinical Pharmacology, Ben-Gurion University of the Negev, Beer Sheva, Israel
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