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Mota CM, Madden CJ. Neural circuits mediating circulating interleukin-1β-evoked fever in the absence of prostaglandin E2 production. Brain Behav Immun 2022; 103:109-121. [PMID: 35429606 PMCID: PMC9524517 DOI: 10.1016/j.bbi.2022.04.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 03/31/2022] [Accepted: 04/10/2022] [Indexed: 10/18/2022] Open
Abstract
Infectious diseases and inflammatory conditions recruit the immune system to mount an appropriate acute response that includes the production of cytokines. Cytokines evoke neurally-mediated responses to fight pathogens, such as the recruitment of thermoeffectors, thereby increasing body temperature and leading to fever. Studies suggest that the cytokine interleukin-1β (IL-1β) depends upon cyclooxygenase (COX)-mediated prostaglandin E2 production for the induction of neural mechanisms to elicit fever. However, COX inhibitors do not eliminate IL-1β-induced fever, thus suggesting that COX-dependent and COX-independent mechanisms are recruited for increasing body temperature after peripheral administration of IL-1β. In the present study, we aimed to build a foundation for the neural circuit(s) controlling COX-independent, inflammatory fever by determining the involvement of brain areas that are critical for controlling the sympathetic outflow to brown adipose tissue (BAT) and the cutaneous vasculature. In anesthetized rats, pretreatment with indomethacin, a non-selective COX inhibitor, did not prevent BAT thermogenesis or cutaneous vasoconstriction (CVC) induced by intravenous IL-1β (2 µg/kg). BAT and cutaneous vasculature sympathetic premotor neurons in the rostral raphe pallidus area (rRPa) are required for IL-1β-evoked BAT thermogenesis and CVC, with or without pretreatment with indomethacin. Additionally, activation of glutamate receptors in the dorsomedial hypothalamus (DMH) is required for COX-independent, IL-1β-induced BAT thermogenesis. Therefore, our data suggests that COX-independent mechanisms elicit activation of neurons within the DMH and rRPa, which is sufficient to trigger and mount inflammatory fever. These data provide a foundation for elucidating the brain circuits responsible for COX-independent, IL-1β-elicited fevers.
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Affiliation(s)
| | - Christopher J. Madden
- Corresponding author at: Dept. of Neurological Surgery, Oregon Health & Science University, 3181 Sam Jackson Park Road, Portland, OR 97239, United States. (C.J. Madden)
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Maba IK, Cruz JV, Zampronio AR. Change in prostaglandin signaling during sickness syndrome hyperalgesia after ovariectomy in female rats. Behav Brain Res 2021; 410:113368. [PMID: 34000337 DOI: 10.1016/j.bbr.2021.113368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 12/26/2022]
Abstract
The present study investigated hyperalgesia during sickness syndrome in female rats. Hyperalgesia was induced by an intraperitoneal injection of lipopolysaccharide (LPS) or an intracerebroventricular injection of prostaglandin E2 (PGE2). No differences were found in basal mechanical and thermal thresholds or in LPS-induced hyperalgesia in sham-operated animals in the diestrus or proestrus phase or in ovariectomized (OVX) animals. However, higher levels of PGE2 where found in the cerebrospinal fluid of OVX animals compared to sham-operated females. Intracerebroventricular injection of PGE2 produced rapid mechanical hyperalgesia in sham-operated rats while these responses were observed at later times in OVX animals. The protein kinase A (PKA) inhibitor H-89 reduced mechanical PGE2-induced hyperalgesia in OVX female rats, whereas no effect was observed in sham-operated animals. In contrast, the exchange protein activated by cyclic adenosine monophosphate (cAMP; Epac) inhibitor ESI-09 reduced mechanical PGE2-induced hyperalgesia, whereas no effect was observed in OVX animals. PGE2 also induced thermal hyperalgesia in sham-operated and OVX female rats and a similar effect of ESI-09 was observed. These results suggest that PGE2-induced hyperalgesia that is observed during sickness syndrome has different signaling mechanisms in cycling and OVX female rats involving the activation of the cAMP-Epac or cAMP-PKA pathways, respectively.
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Affiliation(s)
- I K Maba
- Department of Pharmacology, Biological Sciences Section, Federal University of Paraná, Curitiba, PR, Brazil
| | - J V Cruz
- Department of Pharmacology, Biological Sciences Section, Federal University of Paraná, Curitiba, PR, Brazil
| | - A R Zampronio
- Department of Pharmacology, Biological Sciences Section, Federal University of Paraná, Curitiba, PR, Brazil.
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Coelho LCM, Cruz JV, Maba IK, Zampronio AR. Fever Induced by Zymosan A and Polyinosinic-Polycytidylic Acid in Female Rats: Influence of Sex Hormones and the Participation of Endothelin-1. Inflammation 2020; 44:321-333. [PMID: 32875489 DOI: 10.1007/s10753-020-01335-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 08/17/2020] [Accepted: 08/27/2020] [Indexed: 01/09/2023]
Abstract
Sex differences in the immune response can also affect the febrile response, particularly the fever induced by lipopolysaccharide (LPS). However, other pathogen-associated molecular patterns, such as zymosan A (Zym) and polyinosinic-polycytidylic acid (Poly I:C), also induce fever in male rats with a different time course of cytokine release and different mediators such as endothelin-1 (ET-1). This study investigated whether female sex hormones affect Zym- and Poly I:C-induced fever and the involvement of ET-1 in this response. The fever that was induced by Zym and Poly I:C was higher in ovariectomized (OVX) female rats compared with sham-operated female rats. Estrogen replacement in OVX females reduced Zym- and Poly I:C-induced fever. The ETB receptor antagonist BQ788 reversed the LPS-induced fever in cycling females but not in OVX females. BQ788 did not alter the fever that was induced by Zym or Poly I:C in either cycling or OVX females. These findings suggest that the febrile response in cycling females is lower, independently of the stimulus that is inducing it and is probably controlled by estrogen. Also, ET-1 seems to participate in the febrile response that was induced by LPS in males and cycling females but not in the LPS-induced fever in OVX females. Additionally, ET-1 was not involved in the febrile response that was induced by Zym or Poly I:C in females.
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Affiliation(s)
- L C M Coelho
- Department of Pharmacology, Federal University of Paraná, Curitiba, PR, Brazil
| | - J V Cruz
- Department of Pharmacology, Federal University of Paraná, Curitiba, PR, Brazil
| | - I K Maba
- Department of Pharmacology, Federal University of Paraná, Curitiba, PR, Brazil
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Brito HO, Radulski D, Wilhelms DB, Stojakovic A, Brito LMO, Gil da Costa RM, Trindade E, Engblom D, Franco CRC, Zampronio AR. Immune-mediated febrile response in female rats: Role of central hypothalamic mediators. Sci Rep 2020; 10:4073. [PMID: 32139801 PMCID: PMC7058003 DOI: 10.1038/s41598-020-61210-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/11/2020] [Indexed: 11/24/2022] Open
Abstract
Lipopolysaccharide (LPS) induces fever through cytokines like receptor-activator of nuclear factor κB ligand (RANKL), triggering mediators like prostaglandins (PG), endothelin-1 (ET-1), corticotrophin-releasing factor (CRF), substance P (SP) and endogenous opioids. LPS-induced fever is reduced in females compared with males except in ovariectomized (OVX) females which show increased fever mediated by PG. The present study aimed to identify the mediators involved in fever in intact and OVX female rats. Fever was induced with LPS (50 μg/kg) intraperitoneally or CRF (2.5 μg), ET-1 (1 pg), morphine (10 μg) and SP (500 ng) intracerebroventricularly in sham-operated and OVX rats. The role of RANKL was evaluated with osteoprotegerin (OPG, 1 μg, intracerebroventricularly). Expression of RANK, CRFI/II, ETB, μ-opioid (MOR) and NK1 receptors was evaluated by confocal microscopy. Besides LPS, only morphine induced fever in OVX rats while all mediators induced fever in sham-operated animals. OPG abolished LPS-induced fever in OVX but not sham-operated animals. Overall, fever involves similar central mediators in cycling females and males but only morphine induced fever in OVX females. Importantly, RANK/RANKL participates in LPS-induced fever in OVX females, as in males but not in cycling females.
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Affiliation(s)
| | - Débora Radulski
- Department of Pharmacology, Federal University of Paraná, Curitiba, PR, Brazil
| | | | | | | | | | - Edvaldo Trindade
- Department of Pharmacology, Federal University of Paraná, Curitiba, PR, Brazil
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Bastos-Pereira AL, Fraga D, Dreifuss AA, Zampronio AR. Central mediators of the zymosan-induced febrile response. J Basic Clin Physiol Pharmacol 2018; 28:555-562. [PMID: 28981444 DOI: 10.1515/jbcpp-2017-0061] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 08/15/2017] [Indexed: 11/15/2022]
Abstract
BACKGROUND Zymosan is a fungal cell wall protein-carbohydrate complex that is known to activate inflammatory pathways through the Toll-like receptors and is commonly used to induce fever. Nevertheless, the central mediators that are involved in the zymosan-induced febrile response are only partially known. METHODS The present study evaluated the participation of prostaglandins, substance P, endothelin-1 (ET-1), and endogenous opioids (eOPs) in the zymosan-induced febrile response by using inhibitors and antagonists in male Wistar rats. RESULTS Both nonselective (indomethacin) and selective (celecoxib) cyclooxygenase inhibitors reduced the febrile response induced by an intraperitoneal (i.p.) injection of zymosan. Indomethacin also blocked the increase in the prostaglandin E2 levels in the cerebrospinal fluid. An intracerebroventricular injection of the neurokinin-1, ETB, and μ-opioid receptor antagonists also reduced the febrile response induced by the i.p. injected zymosan. Moreover, the μ-opioid receptor antagonist CTAP also reduced the febrile response induced by intra-articular injection of zymosan. CONCLUSIONS These results demonstrate that prostaglandins, substance P, ET-1, and eOPs are central mediators of the zymosan-induced febrile response.
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Central fractalkine stimulates central prostaglandin E 2 production and induces systemic inflammatory responses. Brain Res Bull 2018; 140:311-317. [PMID: 29870777 DOI: 10.1016/j.brainresbull.2018.05.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 04/23/2018] [Accepted: 05/31/2018] [Indexed: 11/20/2022]
Abstract
Fractalkine (FKN; CX3CL1) belongs to gamma-chemokine family and binds to CX3CR1 receptors. Currently, the mechanisms involving FKN-induced inflammatory mediators are research targets in an attempt to study immune diseases mechanisms. Besides, FKN seems to modulate inflammation in the nervous system by inducing the secretion of pro-inflammatory mediators such as prostaglandin E2 (PGE2). PGE2 is a classic and important mediator of fever that activates warm-responsive neurons in the anteroventral preoptic region of the hypothalamus (AVPO). Here, we tested the hypothesis that central FKN modulates febrigenic signaling both centrally and peripherally. We performed intracerebroventricular (icv) microinjections of saline (1 μL) or FKN (doses of 5, 50, 500 pg/μL) in rats and measured body temperature (Tb) besides assessing tail skin temperature (Tsk) as a thermoeffector indicator used to calculate the heat loss index (HLI). We also measured the time course changes in AVPO PGE2, besides plasma corticosterone (CORT) and interleukin-6 (IL-6) levels. FKN induced a long lasting febrile response in which the highest dose (500 pg/μL) induced a marked rise on Tb that was accompanied by a reduced Tsk and HLI, consequently. FKN increased AVPO PGE2 production in a time-dependent manner besides increasing plasma CORT and IL-6 levels. Our data consistently indicate that FKN increases AVPO PGE2 production and Tb, accompanied by raised plasma IL-6 levels and activation of the hypothalamus-pituitary-adrenal axis.
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Mu and kappa opioid receptors of the periaqueductal gray stimulate and inhibit thermogenesis, respectively, during psychological stress in rats. Pflugers Arch 2017; 469:1151-1161. [DOI: 10.1007/s00424-017-1966-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 02/20/2017] [Accepted: 03/06/2017] [Indexed: 12/18/2022]
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Telles TM, de Oliveira BM, Lomba LA, Leite-Avalca MG, Correia D, Zampronio AR. Effects of Binge-Like Ethanol Exposure During Adolescence on the Febrile Response in Rats. Alcohol Clin Exp Res 2017; 41:507-515. [DOI: 10.1111/acer.13333] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 12/26/2016] [Indexed: 01/26/2023]
Affiliation(s)
| | | | - Luis A. Lomba
- Department of Pharmacology; Federal University of Paraná; Curitiba PR Brazil
| | | | - Diego Correia
- Department of General Biology; Federal University of Minas Gerais; Belo Horizonte MG Brazil
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Brito HO, Radulski DR, Wilhelms DB, Stojakovic A, Brito LMO, Engblom D, Franco CRC, Zampronio AR. Female Sex Hormones Influence the Febrile Response Induced by Lipopolysaccharide, Cytokines and Prostaglandins but not by Interleukin-1β in Rats. J Neuroendocrinol 2016; 28. [PMID: 27483048 DOI: 10.1111/jne.12414] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 07/05/2016] [Accepted: 07/29/2016] [Indexed: 11/26/2022]
Abstract
There are differences in the immune response, and particularly fever, between males and females. In the present study, we investigated how the febrile responses induced by lipopolysaccharide (LPS) and different endogenous pyrogens were affected by female gonadal hormones. The febrile response to i.p. injection of LPS (50 μg/kg) was 40% lower in female rats compared to male or ovariectomised (OVX) female rats. Accordingly, oestrogen replacement in OVX animals reduced LPS-induced fever. Treatment with the prostaglandin synthesis inhibitor indomethacin (2 mg/kg, i.p. 30 min before) reduced the febrile response induced by LPS in both OVX (88%) and sham-operated (71%) rats. In line with the enhanced fever in OVX rats, there was increased expression of cyclooxygenase-2 (COX-2) in the hypothalamus and elevated levels of prostaglandin E2 (PGE2 ). In addition, OVX rats were hyper-responsive to PGE2 injected i.c.v. By contrast to the enhanced fever in response to LPS and PGE2 , the febrile response induced by i.c.v. injection of interleukin (IL)-1β was unaffected by ovariectomy, whereas the responses induced by tumour necrosis factor (TNF)-α and macrophage inflammatory protein (MIP)-1α were completely abrogated. These results suggest that the mediators involved in the febrile response in females are similar to males, although the reduction of female hormones may decrease the responsiveness of some mediators such as TNF-α and MIP-1α. Compensatory mechanisms may be activated in females after ovariectomy such as an augmented synthesis of COX-2 and PGE2 .
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Affiliation(s)
- H O Brito
- Department of Pharmacology, Federal University of Paraná, Curitiba, Brazil
| | - D R Radulski
- Department of Pharmacology, Federal University of Paraná, Curitiba, Brazil
| | - D B Wilhelms
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - A Stojakovic
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - L M O Brito
- Department of Medicine III, Federal University of Maranhão, São Luís, Brazil
| | - D Engblom
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - C R C Franco
- Department of Cell Biology, Federal University of Paraná, Curitiba, Brazil
| | - A R Zampronio
- Department of Pharmacology, Federal University of Paraná, Curitiba, Brazil.
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Evidence of substance P autocrine circuitry that involves TNF-α, IL-6, and PGE2 in endogenous pyrogen-induced fever. J Neuroimmunol 2016; 293:1-7. [DOI: 10.1016/j.jneuroim.2016.01.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 01/11/2016] [Accepted: 01/25/2016] [Indexed: 11/23/2022]
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Fraga D, Zanoni CIS, Zampronio AR, Parada CA, Rae GA, Souza GEP. Endocannabinoids, through opioids and prostaglandins, contribute to fever induced by key pyrogenic mediators. Brain Behav Immun 2016; 51:204-211. [PMID: 26291402 DOI: 10.1016/j.bbi.2015.08.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 08/05/2015] [Accepted: 08/14/2015] [Indexed: 02/08/2023] Open
Abstract
This study aims to explore the contribution of endocannabinoids on the cascade of mediators involved in LPS-induced fever and to verify the participation of prostaglandins and endogenous opioids in fever induced by anandamide (AEA). Body temperature (Tc) of male Wistar rats was recorded over 6h, using a thermistor probe. Cerebrospinal fluid concentration of PGE2 and β-endorphin were measured by ELISA after the administration of AEA. Intracerebroventricular administration of the CB1 receptor antagonist AM251 (5μg, i.c.v.), reduced the fever induced by IL-1β (3ng, i.c.v.), TNF-α (250ng, i.c.v.), IL-6 (300ng, i.c.v.), corticotrophin release factor (CRH; 2.5μg, i.c.v.) and endothelin (ET)-1 (1pmol, i.c.v.), but not the fever induced by PGE2 (250ng, i.c.v.) or PGF2α (250ng, i.c.v.). Systemic administration of indomethacin (2mgkg(-1), i.p.) or celecoxib (5mgkg(-1), p.o.) reduced the fever induced by AEA (1μg, i.c.v.), while naloxone (1mgkg(-1), s.c.) abolished it. The increases of PGE2 and β-endorphin concentration in the CSF induced by AEA were abolished by the pretreatment of rats with AM251. These results suggest that endocannabinoids are intrinsically involved in the pyretic activity of cytokines (IL-1β, TNF-α, IL-6), CRH and ET-1 but not the PGE2 or PGF2α induced fevers. However, anandamide via CB1 receptor activation induces fever that is dependent on the synthesis of prostaglandin and opioids.
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Affiliation(s)
- Daniel Fraga
- Laboratory of Pharmacology, Faculty of Pharmaceutical Sciences, University of São Paulo, Ribeirão Preto, SP, Brazil; Faculty of Nursing, Federal University of Mato Grosso of Sul, Coxim, MS, Brazil.
| | - Cristiane I S Zanoni
- Laboratory of Neuropathic Pain, Department of Pharmacology, Institute of Biomedical Sciences, São Paulo, Brazil
| | | | - Carlos A Parada
- Biology Institute, University of Campinas, UNICAMP, Campinas, SP, Brazil
| | - Giles A Rae
- Department of Pharmacology, Biological Science Center, Federal University of Santa Catarina, Brazil
| | - Glória E P Souza
- Laboratory of Pharmacology, Faculty of Pharmaceutical Sciences, University of São Paulo, Ribeirão Preto, SP, Brazil
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Szkutnik-Fiedler D, Billert H, Grabowski T, Lisiecka J, Michalak M, Urjasz H, Grześkowiak E. Effects of Low-Dose Escherichia coli Lipopolysaccharide-Induced Endotoxemia on Morphine Pharmacokinetics in an Animal Model. PAIN MEDICINE 2015; 17:1407-15. [PMID: 26814265 DOI: 10.1093/pm/pnv030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 09/13/2015] [Indexed: 01/17/2023]
Abstract
OBJECTIVE Systemic inflammation may change the bioavailability and pharmacokinetics of opioids. However, there are insufficient data on morphine pharmacokinetics in mild inflammatory conditions. This study aimed to determine the pharmacokinetics of morphine during low-dose endotoxemia in rabbits. DESIGN In two experiments (separated by a 14-day washout period), 10 rabbits received intravenous morphine at a dose of 3 mg/kg. In the second set of experiments, morphine infusion was preceded by low-dose endotoxemia induced with lipopolysaccharide (Escherichia coli 0111: B4) at a dose of 5 µg/kg. The kinetics of systemic morphine concentrations and chosen physiological parameters were measured at specific time intervals up to 6 hours after morphine administration. RESULTS In endotoxemia, decreased elimination half-life (P = 0.017), mean residence time (P = 0.022), and volume of distribution (P = 0.037) as well as an increased elimination rate constant (P = 0.013) and total body clearance (P = 0.023) were noted. The inverse linear correlation between morphine clearance versus the percentage (%) change in body temperature and pulse rate observed under control conditions was abolished under endotoxemia. CONCLUSIONS Low-dose endotoxemia is correlated with significant alterations in morphine pharmacokinetics in rabbits, leading to the faster elimination of the drug. CLINICAL IMPLICATIONS These findings may have important implications in patients with low-grade inflammation and imply the need to modify morphine dosing regimens to ensure optimal analgesia. The issue warrants further experimental and clinical investigation.
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Affiliation(s)
| | | | | | | | - Michał Michalak
- Computer Sciences and Statistics, Poznan University of Medical Sciences, Poznań, Poland
| | - Hanna Urjasz
- Departments of *Clinical Pharmacy and Biopharmacy
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Zampronio AR, Soares DM, Souza GEP. Central mediators involved in the febrile response: effects of antipyretic drugs. Temperature (Austin) 2015; 2:506-21. [PMID: 27227071 PMCID: PMC4843933 DOI: 10.1080/23328940.2015.1102802] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2015] [Revised: 09/24/2015] [Accepted: 09/29/2015] [Indexed: 11/13/2022] Open
Abstract
Fever is a complex signal of inflammatory and infectious diseases. It is generally initiated when peripherally produced endogenous pyrogens reach areas that surround the hypothalamus. These peripheral endogenous pyrogens are cytokines that are produced by leukocytes and other cells, the most known of which are interleukin-1β, tumor necrosis factor-α, and interleukin-6. Because of the capacity of these molecules to induce their own synthesis and the synthesis of other cytokines, they can also be synthesized in the central nervous system. However, these pyrogens are not the final mediators of the febrile response. These cytokines can induce the synthesis of cyclooxygenase-2, which produces prostaglandins. These prostanoids alter hypothalamic temperature control, leading to an increase in heat production, the conservation of heat, and ultimately fever. The effect of antipyretics is based on blocking prostaglandin synthesis. In this review, we discuss recent data on the importance of prostaglandins in the febrile response, and we show that some endogenous mediators can still induce the febrile response even when known antipyretics reduce the levels of prostaglandins in the central nervous system. These studies suggest that centrally produced mediators other than prostaglandins participate in the genesis of fever. Among the most studied central mediators of fever are corticotropin-releasing factor, endothelins, chemokines, endogenous opioids, and substance P, which are discussed herein. Additionally, recent evidence suggests that these different pathways of fever induction may be activated during different pathological conditions.
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Affiliation(s)
- Aleksander R Zampronio
- Department of Pharmacology; Biological Sciences Section; Federal University of Paraná ; Curitiba, PR, Brazil
| | - Denis M Soares
- Department of Medicament; Faculty of Pharmacy; Federal University of Bahia ; Salvador, BA, Brazil
| | - Glória E P Souza
- Discipline of Pharmacology; Faculty of Pharmaceutical Sciences of Ribeirão Preto; University of São Paulo ; Ribeirão Preto, SP, Brazil
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Zampronio AR, Soares DM, Souza GEP. Central mediators involved in the febrile response: effects of antipyretic drugs. Temperature (Austin) 2015. [PMID: 27227071 DOI: 10.1080/23328940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/24/2023] Open
Abstract
Fever is a complex signal of inflammatory and infectious diseases. It is generally initiated when peripherally produced endogenous pyrogens reach areas that surround the hypothalamus. These peripheral endogenous pyrogens are cytokines that are produced by leukocytes and other cells, the most known of which are interleukin-1β, tumor necrosis factor-α, and interleukin-6. Because of the capacity of these molecules to induce their own synthesis and the synthesis of other cytokines, they can also be synthesized in the central nervous system. However, these pyrogens are not the final mediators of the febrile response. These cytokines can induce the synthesis of cyclooxygenase-2, which produces prostaglandins. These prostanoids alter hypothalamic temperature control, leading to an increase in heat production, the conservation of heat, and ultimately fever. The effect of antipyretics is based on blocking prostaglandin synthesis. In this review, we discuss recent data on the importance of prostaglandins in the febrile response, and we show that some endogenous mediators can still induce the febrile response even when known antipyretics reduce the levels of prostaglandins in the central nervous system. These studies suggest that centrally produced mediators other than prostaglandins participate in the genesis of fever. Among the most studied central mediators of fever are corticotropin-releasing factor, endothelins, chemokines, endogenous opioids, and substance P, which are discussed herein. Additionally, recent evidence suggests that these different pathways of fever induction may be activated during different pathological conditions.
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Affiliation(s)
- Aleksander R Zampronio
- Department of Pharmacology; Biological Sciences Section; Federal University of Paraná ; Curitiba, PR, Brazil
| | - Denis M Soares
- Department of Medicament; Faculty of Pharmacy; Federal University of Bahia ; Salvador, BA, Brazil
| | - Glória E P Souza
- Discipline of Pharmacology; Faculty of Pharmaceutical Sciences of Ribeirão Preto; University of São Paulo ; Ribeirão Preto, SP, Brazil
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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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Kanashiro A, Figueiredo MJ, Malvar DDC, Souza GEP. Cytokines, but not corticotropin-releasing factor and endothelin-1, participate centrally in the febrile response in zymosan-induced arthritis in rats. Brain Res 2015; 1610:12-9. [PMID: 25819555 DOI: 10.1016/j.brainres.2015.03.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 02/13/2015] [Accepted: 03/19/2015] [Indexed: 02/07/2023]
Abstract
Recent literature has revealed that centrally generated prostaglandins participate in the febrile response in zymosan-induced arthritis in rats. However, it is not clear whether other centrally acting pyrogenic mediators such as cytokines, endothelins (ETs), and the corticotropin-releasing factor (CRF) contribute to the febrile response in this model. In the present study, rats were pretreated with intracerebroventricular (i.c.v.) injections of soluble TNF receptor I (sTNFRI), recombinant IL-1 receptor antagonist (IL-1ra), anti-rat IL-6 monoclonal antibody (AbIL-6), α-helical CRF9-41 (a nonselective CRF1/CRF2 receptor antagonist), BQ-123 (an ETA receptor antagonist), BQ-788 (an ETB receptor antagonist), and artificial cerebrospinal fluid (aCSF, control) prior to an intra-articular zymosan (4 mg) injection. Rectal temperatures were measured with a telethermometer. The administration of IL-1ra (200 µg), sTNFRI (500 ng), and AbIL-6 (5 µg) attenuated body temperature elevations after a zymosan injection. The administration of BQ-788 (3 pmol), BQ-123 (3 pmol), and α-helical CRF9-41 (25 µg) did not affect the zymosan-induced febrile response. All the compounds used to pretreat the animals did not significantly alter their basal body temperatures. Together, the results here demonstrate that the febrile response in zymosan-induced arthritis in rats depends on the centrally acting pyrogenic cytokines TNF-α, IL-1β, and IL-6, but does not depend on either CRF or ET-1.
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Affiliation(s)
- Alexandre Kanashiro
- Laboratory of Pharmacology, Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Av. do Café s/n, Ribeirão Preto 14040-903, SP, Brazil
| | - Maria J Figueiredo
- Laboratory of Pharmacology, Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Av. do Café s/n, Ribeirão Preto 14040-903, SP, Brazil
| | - David do C Malvar
- Laboratory of Pharmacology, Department of Physiologic Sciences, Federal Rural University of Rio de Janeiro, BR 465/Km 07, Seropédica 23890-000, RJ, Brazil
| | - Glória E P Souza
- Laboratory of Pharmacology, Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Av. do Café s/n, Ribeirão Preto 14040-903, SP, Brazil.
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17
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Bastos-Pereira AL, Leite MCG, Fraga D, Zampronio AR. Central mediators involved in the febrile response induced by polyinosinic-polycytidylic acid: lack of involvement of endothelins and substance P. J Neuroimmunol 2014; 278:100-7. [PMID: 25595258 DOI: 10.1016/j.jneuroim.2014.12.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 12/08/2014] [Accepted: 12/11/2014] [Indexed: 12/18/2022]
Abstract
The present study evaluated the involvement of interleukin(IL)-1β, tumor necrosis factor-α (TNF-α), IL-6, interferon(IFN)-γ, prostaglandins of the E2 series, endothelins, substance P and opioids within the central nervous system in polyinosinic:polycytidylic acid (Poly I:C)-induced fever in rats. Poly I:C injection induced a febrile response which was reduced by intracerebroventricular administration of the antibodies against TNF-α, IL-6, or IFN-γ, or by IL-1 or μ receptor antagonists. Intraperitoneal injection of indomethacin or oral administration of celecoxib also reduced Poly I:C-induced fever. Poly I:C increased prostaglandin E2 levels in the cerebrospinal fluid of the animals which was also reduced by indomethacin. The intracerebroventricular injection of ETB or NK1 receptor antagonists did not alter Poly I:C-induced fever. These data suggest the involvement of IL-1β, TNF-α, IL-6, IFN-γ, prostaglandin E2, and opioids but not endothelins and substance P on Poly I:C-induced fever.
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Affiliation(s)
- A L Bastos-Pereira
- Department of Pharmacology, Federal University of Paraná, P.O. Box 19031, 81540-970 Curitiba, PR, Brazil
| | - M C G Leite
- Department of Pharmacology, Federal University of Paraná, P.O. Box 19031, 81540-970 Curitiba, PR, Brazil
| | - D Fraga
- Department of Pharmacology, Federal University of Paraná, P.O. Box 19031, 81540-970 Curitiba, PR, Brazil
| | - A R Zampronio
- Department of Pharmacology, Federal University of Paraná, P.O. Box 19031, 81540-970 Curitiba, PR, Brazil.
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18
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Bastos-Pereira AL, Fraga D, Ott D, Simm B, Murgott J, Roth J, Zampronio AR. Involvement of brain cytokines in zymosan-induced febrile response. J Appl Physiol (1985) 2014; 116:1220-9. [DOI: 10.1152/japplphysiol.01278.2013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
This study compared the involvement of interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) within the central nervous system (CNS) in the febrile response induced by zymosan (zym) and lipopolysaccharide (LPS). In addition, we investigated whether zym could activate important regions related to fever; namely, the vascular organ of the laminae terminalis (OVLT) and the median preoptic nucleus (MnPO). Intraperitoneal injection of zym (1, 3, and 10 mg/kg) induced a dose-related increase in core temperature. Zym (3 mg/kg) also reduced tail skin temperature, suggesting the activation of heat conservation mechanisms, as expected, during fever. LPS increased plasma levels of TNF-α measured at 1 h, IL-1β measured at 2 h, and IL-6 measured at 3 h after injection. Zym increased circulating levels of IL-6 but not those of TNF-α or IL-1β at the same time points. In addition, an intracerebroventricular injection of antibodies against TNF-α (2.5 μg) and IL-6 (10 μg) or the IL-1 receptor antagonist (160 ng) reduced the febrile response induced by zym and LPS. Zym (100 μg/ml) also increased intracellular calcium concentration in the OVLT and MnPO from rat primary neuroglial cultures and increased release of TNF-α and IL-6 into the supernatants of these cultures. Together, these results suggest that TNF-α, IL-1β, and IL-6 within the CNS participate in the febrile response induced by zym. However, the time course of release of these cytokines may be different from that of LPS. In addition, zym can directly activate the brain areas related to fever.
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Affiliation(s)
| | - Daniel Fraga
- Department of Pharmacology, Federal University of Paraná, Curitiba, Brazil; and
| | - Daniela Ott
- Institut für Veterinär-Physiologie, Justus-Liebig University, Giessen, Germany
| | - Björn Simm
- Institut für Veterinär-Physiologie, Justus-Liebig University, Giessen, Germany
| | - Jolanta Murgott
- Institut für Veterinär-Physiologie, Justus-Liebig University, Giessen, Germany
| | - Joachim Roth
- Institut für Veterinär-Physiologie, Justus-Liebig University, Giessen, Germany
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19
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Megremi AS. Is fever a predictive factor in the autism spectrum disorders? Med Hypotheses 2013; 80:391-8. [PMID: 23394936 DOI: 10.1016/j.mehy.2013.01.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 01/04/2013] [Accepted: 01/05/2013] [Indexed: 02/08/2023]
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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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21
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Kovács Z, Czurkó A, Kékesi KA, Juhász G. Intracerebroventricularly administered lipopolysaccharide enhances spike–wave discharges in freely moving WAG/Rij rats. Brain Res Bull 2011; 85:410-6. [DOI: 10.1016/j.brainresbull.2011.05.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 03/19/2011] [Accepted: 05/08/2011] [Indexed: 12/15/2022]
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22
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Reis R, Brito H, Fraga D, Cabrini D, Zampronio A. Central substance P NK1 receptors are involved in fever induced by LPS but not by IL-1β and CCL3/MIP-1α in rats. Brain Res 2011; 1384:161-9. [DOI: 10.1016/j.brainres.2011.02.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 01/31/2011] [Accepted: 02/01/2011] [Indexed: 10/18/2022]
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23
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The long-term impact of footshock stress on addiction-related behaviors in rats. Neuropharmacology 2011; 60:267-73. [DOI: 10.1016/j.neuropharm.2010.09.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 08/20/2010] [Accepted: 09/07/2010] [Indexed: 01/31/2023]
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24
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Inoue W, Luheshi GN. Acute starvation alters lipopolysaccharide-induced fever in leptin-dependent and -independent mechanisms in rats. Am J Physiol Regul Integr Comp Physiol 2010; 299:R1709-19. [DOI: 10.1152/ajpregu.00567.2010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A decrease in leptin levels with the onset of starvation triggers a myriad of physiological responses including immunosuppression and hypometabolism/hypothermia, both of which can counteract the fever response to pathogens. Here we examined the role of leptin in LPS-induced fever in rats that were fasted for 48 h prior to inflammation with or without leptin replacement (12 μg/day). The preinflammation fasting alone caused a progressive hypothermia that was almost completely reversed by leptin replacement. The LPS (100 μg/kg)-induced elevation in core body temperature ( T core) was attenuated in the fasted animals at 2–6 h after the injection, an effect that was not reversed by leptin replacement. Increasing the LPS dose to 1,000 μg/kg caused a long-lasting fever that remained unabated for up to 36 h after the injection in the fed rats. This sustained response was strongly attenuated in the fasted rats whose T core started to decrease by 18 h after the injection. Leptin replacement almost completely restored the prolonged fever. The attenuation of the prolonged fever in the fasted animals was accompanied by the diminution of proinflammatory PGE2 in the cerebrospinal fluid and mRNA of proopiomelanocortin (POMC) in the hypothalamus. Leptin replacement prevented the fasting-induced reduction of POMC but not PGE2. Moreover, the leptin-dependent fever maintenance correlated closely with hypothalamic POMC levels ( r = 0.77, P < 0.001). These results suggest that reduced leptin levels during starvation attenuate the sustained fever response by lowering hypothalamic POMC tone but not PGE2 synthesis.
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Affiliation(s)
- Wataru Inoue
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, Quebec, Canada
| | - Giamal N. Luheshi
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, Quebec, Canada
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25
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Fraga D, Zanoni CIS, Rae GA, Parada CA, Souza GEP. Endogenous cannabinoids induce fever through the activation of CB1 receptors. Br J Pharmacol 2010; 157:1494-501. [PMID: 19681872 DOI: 10.1111/j.1476-5381.2009.00312.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE The effects of centrally administered cannabinoids on body core temperature (Tc) and the contribution of endogenous cannabinoids to thermoregulation and fever induced by lipopolysaccharide (LPS) (Sigma Chem. Co., St. Louis, MO, USA) were investigated. EXPERIMENTAL APPROACH Drug-induced changes in Tc of male Wistar rats were recorded over 6 h using a thermistor probe (Yellow Springs Instruments 402, Dayton, OH, USA) inserted into the rectum. KEY RESULTS Injection of anandamide [(arachidonoylethanolamide (AEA); Tocris, Ellisville, MO, USA], 0.01-1 microg i.c.v. or 0.1-100 ng intra-hypothalamic (i.h.), induced graded increases in Tc (peaks 1.5 and 1.6 degrees C at 4 h after 1 microg i.c.v. or 10 ng i.h.). The effect of AEA (1 microg, i.c.v.) was preceded by decreases in tail skin temperature and heat loss index (values at 1.5 h: vehicle 0.62, AEA 0.48). Bell-shaped curves were obtained for the increase in Tc induced by the fatty acid amide hydrolase inhibitor [3-(3-carbamoylphenyl)phenyl] N-cyclohexylcarbamate (Cayman Chemical Co., Ann Arbor, MI, USA) (0.001-1 ng i.c.v.; peak 1.9 degrees C at 5 h after 0.1 ng) and arachidonyl-2-chloroethylamide (ACEA; Tocris) (selective CB(1) agonist; 0.001-1 microg i.c.v.; peak 1.4 degrees C 5 h after 0.01 microg), but (R,S)-(+)-(2-Iodo-5-nitrobenzoyl)-[1-(1-methyl-piperidin-2-ylmethyl)-1H-indole-3-yl] methanone (Tocris) (selective CB(2) agonist) had no effect on Tc. AEA-induced fever was unaffected by i.c.v. pretreatment with 6-Iodo-2-methyl-1-[2-(4-morpholinyl)ethyl]-1H-indole-3-yl](4-methoxyphenyl) methanone (Tocris) (selective CB(2) antagonist), but reduced by i.c.v. pretreatment with N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251; Tocris) (selective CB(1) antagonist). AM251 also reduced the fever induced by ACEA or LPS. CONCLUSIONS AND IMPLICATIONS The endogenous cannabinoid AEA induces an integrated febrile response through activation of CB(1) receptors. Endocannabinoids participate in the development of the febrile response to LPS constituting a target for antipyretic therapy.
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Affiliation(s)
- D Fraga
- Laboratory of Pharmacology, Faculty of Pharmaceutical Sciences, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
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Abstract
This paper is the 31st consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2008 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, 65-30 Kissena Blvd, Flushing, NY 11367, United States.
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27
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Role of preoptic opioid receptors in the body temperature reduction during hypoxia. Brain Res 2009; 1286:66-74. [DOI: 10.1016/j.brainres.2009.06.039] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2009] [Revised: 06/10/2009] [Accepted: 06/13/2009] [Indexed: 11/16/2022]
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