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Maganga-Bakita I, Aiken AA, Puracchio MJ, Kentner AC, Hunter RG. Regulatory Effects of Maternal Immune Activation and Environmental Enrichment on Glucocorticoid Receptor and FKBP5 Expression in Stress-sensitive Regions of the Offspring Brain. Neuroscience 2022; 505:51-58. [PMID: 36116554 PMCID: PMC9888218 DOI: 10.1016/j.neuroscience.2022.09.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 09/05/2022] [Accepted: 09/08/2022] [Indexed: 02/02/2023]
Abstract
A mother's exposure to immune challenge during pregnancy is well known to be a detrimental factor to the development of the offspring's brain and an impetus for neuropsychiatric disorders. Previous studies have shown that these adverse events can dysregulate the stress response machinery. Two crucial components of the stress axis considered to be affected have been targets in these studies: the glucocorticoid receptor (GR), and FKBP5 which regulates GR activity. The implementation of interventions such as Environmental Enrichment (EE) have shown positive results in protecting the brain against the consequences associated with gestational insults. In light of this, we investigated the transcriptional regulation of GR and FKBP5 from six stress-sensitive brain regions of the offspring using a rat model of maternal immune activation (MIA). Furthermore, we analyzed the effect of an enriched environment on their expression. We found an increase in FKBP5 in MIA rats in five brain regions. RT-qPCR analysis of MIA's effect on GR yielded insignificant results. However, we found that EE increased GR expression in the medial preoptic area which could be indicative of a positive regulation by EE. This study provides evidence of the impact of both gestational insult and EE on the regulation of stress responsive genes in the developing brain.
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Affiliation(s)
| | - Ariel A Aiken
- University of Massachusetts Boston, Department of Psychology, Boston, MA, USA
| | - Madeline J Puracchio
- Massachusetts College of Pharmacy and Health Sciences, Department of Psychology, Boston, MA, USA
| | - Amanda C Kentner
- Massachusetts College of Pharmacy and Health Sciences, Department of Psychology, Boston, MA, USA
| | - Richard G Hunter
- University of Massachusetts Boston, Department of Psychology, Boston, MA, USA.
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Liu J, Lai F, Hou Y, Zheng R. Leptin signaling and leptin resistance. MEDICAL REVIEW (BERLIN, GERMANY) 2022; 2:363-384. [PMID: 37724323 PMCID: PMC10388810 DOI: 10.1515/mr-2022-0017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 07/12/2022] [Indexed: 09/20/2023]
Abstract
With the prevalence of obesity and associated comorbidities, studies aimed at revealing mechanisms that regulate energy homeostasis have gained increasing interest. In 1994, the cloning of leptin was a milestone in metabolic research. As an adipocytokine, leptin governs food intake and energy homeostasis through leptin receptors (LepR) in the brain. The failure of increased leptin levels to suppress feeding and elevate energy expenditure is referred to as leptin resistance, which encompasses complex pathophysiological processes. Within the brain, LepR-expressing neurons are distributed in hypothalamus and other brain areas, and each population of the LepR-expressing neurons may mediate particular aspects of leptin effects. In LepR-expressing neurons, the binding of leptin to LepR initiates multiple signaling cascades including janus kinase (JAK)-signal transducers and activators of transcription (STAT) phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT), extracellular regulated protein kinase (ERK), and AMP-activated protein kinase (AMPK) signaling, etc., mediating leptin actions. These findings place leptin at the intersection of metabolic and neuroendocrine regulations, and render leptin a key target for treating obesity and associated comorbidities. This review highlights the main discoveries that shaped the field of leptin for better understanding of the mechanism governing metabolic homeostasis, and guides the development of safe and effective interventions to treat obesity and associated diseases.
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Affiliation(s)
- Jiarui Liu
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Health Science Center, Peking University, Beijing, China
| | - Futing Lai
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Health Science Center, Peking University, Beijing, China
| | - Yujia Hou
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Health Science Center, Peking University, Beijing, China
| | - Ruimao Zheng
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Health Science Center, Peking University, Beijing, China
- Neuroscience Research Institute, Peking University, Beijing, China
- Key Laboratory for Neuroscience of Ministry of Education, Peking University, Beijing, China
- Key Laboratory for Neuroscience of National Health Commission, Peking University, Beijing 100191, China
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Liu J, Yang X, Yu S, Zheng R. The Leptin Signaling. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1090:123-144. [PMID: 30390288 DOI: 10.1007/978-981-13-1286-1_7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Leptin plays a critical role in the regulation of energy balance and metabolic homeostasis. Impairment of leptin signaling is closely involved in the pathogenesis of obesity and metabolic diseases, including diabetes, cardiovascular disease, etc. Leptin initiates its intracellular signaling in the leptin-receptor-expressing neurons in the central nervous system to exert physiological function, thereby leading to a suppression of appetite, a reduction of food intake, a promotion of mitochondrial oxidation, an enhancement of thermogenesis, and a decrease in body weight. In this review, the studies on leptin neural and cellular pathways are summarized with an emphasis on the progress made during the last 10 years, for better understanding the molecular mechanism of obesity and other metabolic diseases.
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Affiliation(s)
- Jiarui Liu
- Department of Anatomy, Histology and Embryology, Health Science Center, Peking University, Beijing, China.,Neuroscience Research Institute, Peking University, Beijing, China.,Key Laboratory for Neuroscience of Ministry of Education, Peking University, Beijing, China.,Key Laboratory for Neuroscience of National Health Commission, Peking University, Beijing, China
| | - Xiaoning Yang
- Department of Anatomy, Histology and Embryology, Health Science Center, Peking University, Beijing, China
| | - Siwang Yu
- Department of Molecular and Cellular Pharmacology, Peking University School of Pharmaceutical Sciences, Beijing, China
| | - Ruimao Zheng
- Department of Anatomy, Histology and Embryology, Health Science Center, Peking University, Beijing, China. .,Neuroscience Research Institute, Peking University, Beijing, China. .,Key Laboratory for Neuroscience of Ministry of Education, Peking University, Beijing, China. .,Key Laboratory for Neuroscience of National Health Commission, Peking University, Beijing, China.
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Fassini A, Scopinho AA, Alves FH, Fortaleza EA, Corrêa FM. The medial preoptic area modulates autonomic function under resting and stress conditions. Neuroscience 2017; 364:164-174. [DOI: 10.1016/j.neuroscience.2017.09.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 09/12/2017] [Accepted: 09/13/2017] [Indexed: 11/26/2022]
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Choudhary RC, Jia X. Hypothalamic or Extrahypothalamic Modulation and Targeted Temperature Management After Brain Injury. Ther Hypothermia Temp Manag 2017; 7:125-133. [PMID: 28467285 PMCID: PMC5610405 DOI: 10.1089/ther.2017.0003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Targeted temperature management (TTM) has been recognized to protect tissue function and positively influence neurological outcomes after brain injury. While shivering during hypothermia nullifies the beneficial effect of TTM, traditionally, antishivering drugs or paralyzing agents have been used to reduce the shivering. The hypothalamic area of the brain helps in controlling cerebral temperature and body temperature through interactions between different brain areas. Thus, modulation of different brain areas either pharmacologically or by electrical stimulation may contribute in TTM; although, very few studies have shown that TTM might be achieved by activation and inhibition of neurons in the hypothalamic region. Recent studies have investigated potential pharmacological methods of inducing hypothermia for TTM by aiming to maintain the TTM and reduce the shivering effect without using antiparalytic drugs. Better survival and neurological outcome after brain injury have been reported after pharmacologically induced TTM. This review discusses the mechanisms and modulation of the hypothalamus with other brain areas that are involved in inducing hypothermia through which TTM may be achieved and provides therapeutic strategies for TTM after brain injury.
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Affiliation(s)
| | - Xiaofeng Jia
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, Maryland
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland
- Department of Biomedical Engineering, The Johns Hopkins University School of Medicine, Baltimore, Maryland
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
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Ingiosi AM, Raymond RM, Pavlova MN, Opp MR. Selective contributions of neuronal and astroglial interleukin-1 receptor 1 to the regulation of sleep. Brain Behav Immun 2015; 48:244-57. [PMID: 25849975 DOI: 10.1016/j.bbi.2015.03.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 03/20/2015] [Accepted: 03/28/2015] [Indexed: 12/26/2022] Open
Abstract
Interactions between sleep and immune function are bidirectional. Although the mechanisms that govern these interactions are not fully elucidated, the pro-inflammatory cytokine, interleukin-1β (IL-1), is a known regulator of sleep and mediator of immune responses. To further clarify the underlying substrates of sleep and immune interactions, we engineered two transgenic mouse lines that express interleukin-1 receptor 1 (IL1R1) only in the central nervous system (CNS) and selectively on neurons (NSE-IL1R1) or astrocytes (GFAP-IL1R1). During spontaneous sleep, compared to wild type (WT) animals, NSE-IL1R1 and GFAP-IL1R1 mice have more rapid eye movement sleep (REMS) that is characterized by reduced theta power in the electroencephalogram (EEG) spectra. The non-REM sleep (NREMS) EEG of each of the IL1R1 transgenic mouse strains also is characterized by enhanced power in the delta frequency band. In response to 6h of sleep deprivation, sleep of both IL1R1 transgenic mouse strains is more consolidated than that of WT animals. Additionally, the NREMS EEG of NSE-IL1R1 mice contains less delta power after sleep deprivation, suggesting astroglial IL1R1 activity may modulate sleep homeostasis. Intracerebroventricular injection of IL-1 fails to alter sleep or brain temperature of NSE-IL1R1 or GFAP-IL1R1 mice. These data suggest that selective IL1R1 expression on neurons or on astrocytes is not sufficient for centrally-administered IL-1 to induce sleep or fever. Lack of sleep and febrile responses to IL-1 in these IL1R1 transgenic mouse strains may be due to their inability to produce IL-6 in brain. Overall, these studies demonstrate, through the use of novel transgenic mice, that IL1R1 on neurons and astrocytes differentially mediates aspects of sleep under physiological conditions and in response to central IL-1 administration.
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Affiliation(s)
- Ashley M Ingiosi
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States; Program in Biomedical Sciences, University of Michigan, Ann Arbor, MI, United States; Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, United States
| | - Richard M Raymond
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, United States
| | - Maria N Pavlova
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, United States
| | - Mark R Opp
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, United States; Program of Neurobiology and Behavior, University of Washington, Seattle, WA, United States.
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Ando M, Ogawa M, Fukuda M. A vagal nerve branch controls swallowing directly in the seawater eel. J Comp Physiol B 2013; 183:1015-21. [PMID: 23748355 DOI: 10.1007/s00360-013-0770-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Revised: 05/14/2013] [Accepted: 05/28/2013] [Indexed: 10/26/2022]
Abstract
By developing a new in vivo method to evaluate the esophageal closure, which reflects inhibition of swallowing, we demonstrate that the vagal X1 branch projected from the glossopharyngeal-vagal motor complex (GVC) controls the upper esophageal sphincter (UES) muscle directly. Although eel vagal nerve consisted of five branches, other branches (X2, X3, X4 and X5) did not influence the esophageal pressure. When the X1 nerve branch was stimulated electrically, the balloon pressure in the UES area increased with optimum frequency of 20 Hz. Since similar optimum frequency was observed both in the pithed eel and in the isolated UES preparation, such characteristic of X1 nerve is not due to anesthetic used during experiment. As the isolated UES preparation consists of muscle cells and nerve terminals, and as the optimum frequency of the nerve terminal is identical with that of the X1 branch, it is most likely that the X1 nerve branch is identical with the nerve terminals within the UES preparation. On the other hand, since the GVC neurons fire spontaneously at around 20 Hz, the optimum frequency of 20 Hz means that the eel UES is usually closed vigorously and relaxed only when the GVC neuron is inactivated. The effect of X1 stimulation was inhibited by curare, but not by atropine, indicating that the X1 nerve branch releases acetylcholine, which acts on the nicotinic receptor on the UES striated muscle. Beside vagal nerve X1 branch, spinal nerve SN2, SN3 and SN4 also contributed to the UES closure, but SN1 did not influence the UES movement. However, since the efficacy of these spinal nerve stimulations is about 1/10 of that by vagal X1 branch, the eel UES may be controlled primarily by a vagal nerve X1 branch, and secondarily by spinal nerves (SN2, SN3 and SN4).
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Affiliation(s)
- Masaaki Ando
- Laboratory of Integrative Physiology, Faculty of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, 739-8521, Japan,
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Brambilla D, Barajon I, Bianchi S, Opp MR, Imeri L. Interleukin-1 inhibits putative cholinergic neurons in vitro and REM sleep when microinjected into the rat laterodorsal tegmental nucleus. Sleep 2010; 33:919-29. [PMID: 20614852 DOI: 10.1093/sleep/33.7.919] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
STUDY OBJECTIVES REM sleep is suppressed during infection, an effect mimicked by the administration of cytokines such as interleukin-1 (IL-1). In spite of this observation, brain sites and neurochemical systems mediating IL-1-induced suppression of REM sleep have not been identified. Cholinergic neurons in the brainstem laterodorsal tegmental nucleus (LDT) are part of the neuronal circuitry responsible for REM sleep generation. Since IL-1 inhibits acetylcholine synthesis and release, the aim of this study was to test the two different, but related hypotheses. We hypothesized that IL-1 inhibits LDT cholinergic neurons, and that, as a result of this inhibition, IL-1 suppresses REM sleep. DESIGN, MEASUREMENT, AND RESULTS To test these hypotheses, the electrophysiological activity of putative cholinergic LDT neurons was recorded in a rat brainstem slice preparation. Interleukin-1 significantly inhibited the firing rate of 76% of recorded putative cholinergic LDT neurons and reduced the amplitude of glutamatergic evoked potentials in 60% of recorded neurons. When IL-1 (1 ng) was microinjected into the LDT of freely behaving rats, REM sleep was reduced by about 50% (from 12.7% +/- 1.5% of recording time [after vehicle] to 6.1% +/- 1.4% following IL-1 administration) during post-injection hours 3-4. CONCLUSIONS Results of this study support the hypothesis that IL-1 can suppress REM sleep by acting at the level of the LDT nucleus. Furthermore this effect may result from the inhibition of evoked glutamatergic responses and of spontaneous firing of putative cholinergic LDT neurons.
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Affiliation(s)
- Dario Brambilla
- Department of Human Physiology, University of Milan Medical School, Milan, Italy
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Tribukait A, Nobel G, Mekjavic IB, Eiken O. Effects of anti-histaminic and anti-cholinergic substances on human thermoregulation during cold provocation. Brain Res Bull 2010; 81:100-6. [PMID: 19576271 DOI: 10.1016/j.brainresbull.2009.06.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Accepted: 06/18/2009] [Indexed: 11/26/2022]
Abstract
The roles of histaminergic and cholinergic neuron systems in the regulation of body temperature have been studied almost exclusively in animals. Recently, we have found that motion sickness, i.e. a condition where hippocampal cholinergic mismatch signals induce a release of histamine in the vomiting centre, accelerates the decline in body temperature in men during exposure to cold. In the present study we measured the thermoregulatory effects of two substances commonly used against motion sickness, i.e. the histamine (H1) receptor blocker dimenhydrinate (DMH) and the muscarine receptor blocker scopolamine (SCOP). In three trials, control (CN), DMH and SCOP, 10 male subjects were immersed in 15 degrees C water for a maximum of 90 min. The trials were separated by a minimum of three days and their order was alternated between subjects. In all trials the subject received, in a double blind fashion, a transdermal patch (SCOP or placebo) 12-14 h before immersion and a tablet (DMH or placebo) 1h before immersion. Mean skin temperature, rectal temperature (T(rec)), the difference in temperature between the non-immersed right forearm and 3rd finger of the right hand (T(ff)), and oxygen uptake (VO(2)) were recorded. The fall in T(rec) was smaller in the DMH than in the CN and SCOP conditions. The recordings of T(ff) and VO(2) suggest that SCOP attenuates peripheral vasoconstriction while DMH increases shivering thermogenesis. Notably, thermal discomfort was reduced in the SCOP condition. Findings are thoroughly discussed in the context of animal studies on the neuropharmacology and neurophysiology of thermoregulation and motion sickness.
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Affiliation(s)
- A Tribukait
- Royal Institute of Technology, School for Technology and Health, Berzelius v. 13, Karolinska Institute, SE 171 77 Stockholm, Sweden.
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Role of brain nitric oxide in the thermoregulation of broiler chicks. Comp Biochem Physiol A Mol Integr Physiol 2009; 154:204-10. [DOI: 10.1016/j.cbpa.2009.06.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2008] [Revised: 06/06/2009] [Accepted: 06/07/2009] [Indexed: 12/11/2022]
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Ishiwata T, Saito T, Hasegawa H, Yazawa T, Kotani Y, Otokawa M, Aihara Y. Changes of body temperature and thermoregulatory responses of freely moving rats during GABAergic pharmacological stimulation to the preoptic area and anterior hypothalamus in several ambient temperatures. Brain Res 2005; 1048:32-40. [PMID: 15913569 DOI: 10.1016/j.brainres.2005.04.027] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2004] [Revised: 04/08/2005] [Accepted: 04/13/2005] [Indexed: 10/25/2022]
Abstract
Action of gamma-aminobutyric acid (GABA) in the preoptic area and anterior hypothalamus (PO/AH) has been implicated to regulate body temperature (T(b)). However, its precise role in thermoregulation remains unclear. Moreover, little is known about its release pattern in the PO/AH during active thermoregulation. Using microdialysis and telemetry techniques, we measured several parameters related to thermoregulation of freely moving rats during pharmacological stimulation of GABA in normal (23 degrees C), cold (5 degrees C), and hot (35 degrees C) ambient temperatures. We also measured extracellular GABA levels in the PO/AH during cold (5 degrees C) and heat (35 degrees C) exposure combined with microdialysis and high performance liquid chromatography (HPLC). Perfusion of GABA(A) agonist muscimol into the PO/AH increased T(b), which is associated with increased heart rate (HR), as an index of heat production in all ambient temperatures. Although tail skin temperature (T(tail)) as an index of heat loss increased only under normal ambient temperatures, its response was relatively delayed in comparison with HR and T(b), suggesting that the increase in T(tail) was a secondary response to increased HR and T(b). Locomotor activity also increased in all ambient temperatures, but its response was not extraordinary. Interestingly, thermoregulatory responses were different after perfusion of GABA(A) antagonist bicuculline at each ambient temperature. In normal ambient temperature conditions, perfusion of bicuculline had no effect on any parameter. However, under cold ambient temperature, the procedure induced significant hypothermia concomitant with a decrease in HR in spite of hyperactivity and increase of T(tail). It induced hyperthermia with the increase of HR but no additional change of T(tail) in hot ambient temperature conditions. Furthermore, the extracellular GABA level increased significantly during cold exposure. Its release was lower during heat exposure than in a normal environment. These results indicate that GABA in the PO/AH is an important neurotransmitter for disinhibition of heat production and inhibition of heat loss under cold ambient temperature. It is a neurotransmitter for inhibition of heat production under hot ambient temperature.
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Affiliation(s)
- Takayuki Ishiwata
- Department of Biology, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minami-ohsawa, Hachioji, Tokyo 192-0397, Japan.
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Rodrigues AG, Lima NRV, Coimbra CC, Marubayashi U. Intracerebroventricular physostigmine facilitates heat loss mechanisms in running rats. J Appl Physiol (1985) 2004; 97:333-8. [PMID: 15033963 DOI: 10.1152/japplphysiol.00742.2003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to evaluate the participation of central cholinergic transmission in the regulation of metabolic rate, core temperature, and heat storage in untrained rats submitted to exercise on a treadmill (20 m/min, 5% inclination) until fatigue. The animals were separated into eight experimental groups, and core temperature or metabolic rate was measured in the rats while they were exercising or while they were at rest after injection of 2 microl of 5 x 10(-3) M physostigmine (Phy) or 0.15 M NaCl solution (Sal) into the lateral cerebral ventricle. Metabolic rate was determined by the indirect calorimetry system, and colonic temperature was recorded as an index of core temperature. In resting animals, Phy induced only a small increase in metabolic rate compared with Sal injection, without having any effect on core temperature. During exercise, the Phy-treated animals showed a lower core heating rate (0.022 +/- 0.003 degrees C/min Phy vs. 0.033 +/- 0.003 degrees C/min Sal; P < 0.02), lower heat storage (285 +/- 37 cal Phy vs. 436 +/- 34 cal Sal; P < 0.02) and lower core temperature at fatigue point than the Sal-treated group (38.5 +/- 0.1 degrees C Phy vs. 39.0 +/- 0.1 degrees C Sal; P < 0.05). However, despite the lower core heating rate, heat storage, and core temperature at fatigue, the Phy-treated rats showed a similar running time compared with the Sal-treated group. We conclude that the activation of the central cholinergic system during exercise increases heat dissipation and attenuates the exercise-induced increase in core temperature without affecting running performance.
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Affiliation(s)
- Alex G Rodrigues
- Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Minas Gerais, Brazil
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Ando M, Mukuda T, Kozaka T. Water metabolism in the eel acclimated to sea water: from mouth to intestine. Comp Biochem Physiol B Biochem Mol Biol 2003; 136:621-33. [PMID: 14662289 DOI: 10.1016/s1096-4959(03)00179-9] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Eels seem to be a suitable model system for analysing regulatory mechanisms of drinking behavior in vertebrates, since most dipsogens and antidipsogens in mammals influence the drinking rate in the seawater eels similarly. The drinking behavior in fishes consists of swallowing alone, since they live in water and water is constantly held in the mouth for respiration. Therefore, contraction of the upper esophageal sphincter (UES) muscle limits the drinking rate in fishes. The UES of the eel was innervated by the glossopharyngeal-vagal motor complex (GVC) in the medulla oblongata (MO). The GVC neurons were immunoreactive to an antibody raised against choline acetyltransferase (ChAT), an acetylcholine (ACh) synthesizing enzyme, indicating that the eel UES muscle is controlled cholinergically by the GVC. The neuronal activity of the GVC was inhibited by adrenaline or dopamine, suggesting catecholaminergic innervation to the GVC. The AP and the commissural nucleus of Cajal (NCC) in the MO projected to the GVC and were immunoreactive to an antibody raised against tyrosine hydroxylase (TH), rate limiting enzyme to produce catecholamines from tyrosine. Therefore, it is likely that activation in the AP or the NCC may inhibit the GVC and thus relaxes the UES muscle, which allows for water to enter into the esophagus. During passing through the esophagus, the imbibed sea water (SW) was desalted to approximately 1/2 SW, which was further diluted in the stomach and arrived at the intestine as approximately 1/3 SW, almost isotonic to the plasma. Finally, from the diluted SW, the eel intestine absorbed water following the Na(+)-K(+)-2Cl(-) cotransport (NKCC2) system. The NaCl and water absorption across the intestine was regulated by various factors, especially by peptides such as atrial natriuretic peptide (ANP) and somatostatin (SS-25 II). During desalination in the esophagus, however, excess salt enters into the blood circulation, which is liable to raise the plasma osmolarity. However, the eel heart was constricted powerfully by the hyperosmolarity, suggesting that the hyperosmolarity enhances the stroke volume to the gill, where excess salt was extruded powerfully via Na(+)-K(+)-2Cl(-) cotransport (NKCC1) system.
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Affiliation(s)
- Masaaki Ando
- Laboratory of Integrative Physiology, Faculty of Integrated Arts and Sciences, Hiroshima University, Kagamiyama 1-7-1, Higashi-Hiroshima 739-8521, Japan.
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Kozaka T, Ando M. Cholinergic innervation to the upper esophageal sphincter muscle in the eel, with special reference to drinking behavior. J Comp Physiol B 2003; 173:135-40. [PMID: 12624651 DOI: 10.1007/s00360-002-0317-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/27/2002] [Indexed: 10/25/2022]
Abstract
To elucidate innervation in the upper esophageal sphincter (UES) muscle of the eel, a key muscle in swallowing, repetitive electrical field stimulation (EFS; 30 mA, 40 V, 300 micros, 10 Hz, 10 trains) was employed. Anatomically, the eel UES muscle consists of striated fibers. The EFS-induced contraction of the UES was completely blocked by tetrodotoxin and curare, and abolished in Ca2+ -free Ringer solution. These results suggest that the EFS stimulates nerve fibers specifically and releases acetylcholine as a neurotransmitter. In fact, acetylcholine and carbachol constricted the UES in a concentration-dependent manner. Even after blocking neuronal firing with tetrodotoxin, acetylcholine constricted the UES muscle, suggesting the existence of acetylcholine receptors on the UES muscle cells. Both EFS- and carbachol-evoked contractions of the UES were blocked by curare at a lower concentration than by atropine or hexamethonium, suggesting that the acetylcholine receptor is nicotinic. Even in Ca2+ -free Ringer solution, a direct current stimulus (2 s duration) constricted the UES muscle to an extent similar to that in the presence of Ca2+, indicating that the muscle contraction itself does not need extracellular Ca2+, i.e., the muscle can be constricted by a release of Ca2+ from the sarcoplasmic reticulum.
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Affiliation(s)
- T Kozaka
- Laboratory of Integrative Physiology, Faculty of Integrated Arts and Sciences, Hiroshima University, 739-8521 Higashi-Hiroshima, Japan
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Kozaka T, Fujii Y, Ando M. Central effects of various ligands on drinking behavior in eels acclimated to seawater. J Exp Biol 2003; 206:687-92. [PMID: 12517986 DOI: 10.1242/jeb.00146] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Intracranial injection of eel angiotensin II (eANG II, 5x10(-13)-5x10(-8) mol), acetylcholine (ACh, 5x10(-12)-5x10(-9) mol), substance P (5x10(-10) mol) and isoproterenol (a beta-adrenoceptor agonist, 5x10(-11)-5x10(-9) mol) enhanced water intake in the seawater eel. The effects of eANG II, ACh and isoproterenol were dose-dependent. By contrast, water intake was inhibited by intracranial injection of eel atrial natriuretic peptide (eANP, 5x10(-13)-5x10(-10) mol), serotonin (5-HT, 5x10(-12)-5x10(-8) mol), ghrelin (5x10(-12)-5x10(-10) mol), gamma-amino butyric acid (GABA, 5x10(-11)-5x10(-8) mol), prolactin (PRL, 5x10(-10)-5x10(-9) mol), arginine vasotocin (AVT, 5x10(-12) mol), vasoactive intestinal peptide (VIP, 5x10(-11) mol), noradrenaline (5x10(-9) mol l(-1)) and phenylephrine (alpha-adrenoceptor agonist, 5x10(-11)-5x10(-9) mol). The inhibitory effects of eANP, 5-HT, ghrelin, GABA, PRL and phenylephrine were dose-dependent. The intracranial stimulatory effect of eANG II was relatively long-lasting compared with the intravenous effect. The stimulatory effect of intravenous eANG II disappeared immediately, and was followed by an inhibition, which could be well explained by an increase in eANP secretion from the atrium.
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Affiliation(s)
- Tomohiro Kozaka
- Laboratory of Integrative Physiology, Faculty of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
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Hajszán T, Zaborszky L. Direct catecholaminergic-cholinergic interactions in the basal forebrain. III. Adrenergic innervation of choline acetyltransferase-containing neurons in the rat. J Comp Neurol 2002; 449:141-57. [PMID: 12115685 DOI: 10.1002/cne.10279] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The central adrenergic neurons have been suggested to play a role in the regulation of arousal and in the neuronal control of the cardiovascular system. To provide morphological evidence that these functions could be mediated via the basal forebrain, we performed correlated light and electron microscopic double-immunolabeling experiments using antibodies against phenylethanolamine N-methyltransferase (PNMT) and choline acetyltransferase, the synthesizing enzymes for adrenaline and acetylcholine, respectively. Most adrenergic/cholinergic appositions were located in the horizontal limb of diagonal band of Broca, within the substantia innominata, and in a narrow band bordering the substantia innominata and the globus pallidus. Quantitative analysis indicated that cholinergic neurons of the substantia innominata receive significantly higher numbers of adrenergic appositions than cholinergic cells in the rest of the basal forebrain. In the majority of cases, the ultrastructural analysis revealed axodendritic asymmetric synapses. By comparing the number and distribution of dopamine beta-hydroxylase (DBH)/cholinergic appositions, described earlier, with those of PNMT/cholinergic interactions in the basal forebrain, it can be concluded that a significant proportion of putative DBH/cholinergic contacts may represent adrenergic input. Our results support the hypothesis that the adrenergic/cholinergic link in the basal forebrain may represent a critical component of a central network coordinating autonomic regulation with cortical activation.
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Affiliation(s)
- Tibor Hajszán
- Center for Molecular and Behavioral Neuroscience, Rutgers, The State University of New Jersey, 197 University Avenue, Newark, NJ 07102, USA
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Takahashi A, Ishimaru H, Ikarashi Y, Kishi E, Maruyama Y. Hypothalamic cholinergic regulation of body temperature and water intake in rats. Auton Neurosci 2001; 94:74-83. [PMID: 11775710 DOI: 10.1016/s1566-0702(01)00347-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Without disturbing the behavior of unanesthetized rats, the perfusion of neostigmine through microdialysis probe into the anterior hypothalamus (AH), paraventricular nucleus (PVN) and lateral ventricle (LV) decreased body temperature and increased water intake. On the other hand, the perfusion into the supraoptic nucleus (SON) increased the body temperature. The perfusion of neostigmine increased the extracellular concentration of acetylcholine in the perfusion sites except LV. Changes, both decrease and increase, in body temperature and increase in water intake were correlated with increases in c-fos-like immunoreactivity (Fos-IR) in the hypothalamus, pons and medulla. Distinct Fos-IR was found in the PVN, SON, median preoptic nucleus (MnPO), locus coeruleus (LC), area postrema and nucleus of the solitary tract (NTS). Co-administration of atropine with neostigmine completely suppressed the changes in the body temperature, water intake and Fos-IR, all of which were induced by the neostigmine perfusion into AH, PVN and SON. In the LV-perfused rats, on the other hand, co-administration of atropine and neostigmine only partially prevented body temperature reduction and still induced significant hypothermia. These results suggest that muscarinic receptor activation in specific regions of the hypothalamus and the activation of LC and NTS are implicated in the regulation of body temperature and water intake. Other receptor processes are involved in the LV-induced changes.
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Affiliation(s)
- A Takahashi
- Department of Neuropsychopharmacology (Tsumura), Gunma University School of Medicine, Maebashi, Japan.
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Kishi E, Takahashi A, Ishimaru H, Ikarashi Y, Maruyama Y. Development of obesity and neurochemical backing in aurothioglucose-treated mice. Auton Neurosci 2001; 92:21-7. [PMID: 11570700 DOI: 10.1016/s1566-0702(01)00305-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To clarify the neurochemical backing of aurothioglucose (ATG)-induced obesity in mice, we investigated lesion sites, hypothalamic neurotransmitters and c-Fos-like immunoreactivity (Fos-IR). At day 2 after ATG, tissue loss or cells death was observed in several parts of the ventral area of the ventromedial hypothalamic nucleus (VMH), and the dorsal area of arcuate nucleus and in the nucleus of the solitary tract (NTS). However, the greater part of the VMH was retained. Body weight began to increase in week 1. Hypothalamic serotonin (5-HT) and the metabolites were increased at day 2. The contents of acetylcholine, norepinephrine and dopamine in the hypothalamus showed no significant change. In week 1, the area shown tissue loss was compacted and plugged up. In the control group, most obvious c-Fos-like immunoreactive region was paraventricular nucleus (PVN). At day 2, Fos-IR was observed around destroyed regions in the hypothalamus and NTS, but few Fos-IR was found in the other regions including PVN. The Fos-IR around destroyed regions diminished after week 1. In week 3, Fos-IR in the PVN increased. These results suggest that the development of ATG-induced obesity cannot be attributed to solely VMH destruction. The restoration processes of the neuronal dysfunction involving PVN seem to play an important role in the development of obesity. NTS lesion and 5-HT system might contribute to decrease in food intake for several days after ATG.
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Affiliation(s)
- E Kishi
- Department of Neuropsychopharmacology (Tsumura), Gunma University School of Medicine, Maebashi, Japan
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Takahashi A, Ishimaru H, Ikarashi Y, Kishi E, Maruyama Y. Opposite regulation of body temperature by cholinergic input to the paraventricular nucleus and supraoptic nucleus in rats. Brain Res 2001; 909:102-11. [PMID: 11478926 DOI: 10.1016/s0006-8993(01)02642-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Hypothalamic cholinergic system plays an important role in the regulation of body temperature and fluid balance. We have previously shown that cholinergic stimulation of the anterior hypothalamus and preoptic area was accompanied by a fall in body temperature, increased water intake, and increased Fos protein in the paraventricular nucleus (PVN) and supraoptic nucleus (SON). In the present study, to estimate the role played by cholinergic input to the PVN and SON in thermoregulation and water intake, we used microdialysis for cholinergic stimulation with neostigmine and analysis of the nucleus, and also investigated immunoreactivity for c-Fos protein in the brain. This stimulation increased extracellular concentration of acetylcholine in these nuclei. Stimulation of the PVN decreased body temperature and increased water intake. On the other hand, stimulation of the SON increased body temperature. Both in PVN-stimulated and SON-stimulated rats, c-Fos-like immunoreactivity (Fos-IR) was evident in the PVN, SON and certain regions including locus coeruleus (LC), area postrema and nucleus of the solitary tract (NTS). Addition of atropine to the dialysis medium attenuated the increase of Fos-IR and suppressed the cholinergic stimulation-induced responses in body temperature and water intake. These results suggest that cholinergic muscarinic mechanisms in PVN and SON play an opposite function in the regulation of body temperature. The same neuronal pathway including LC and NTS may participate in an advance both in hypothermia and in hyperthermia.
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Affiliation(s)
- A Takahashi
- Department of Neuropsychopharmacology (Tsumura), Gunma University School of Medicine, Maebashi, 371-8511, Gunma, Japan.
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Takahashi A, Ishimaru H, Ikarashi Y, Kishi E, Maruyama Y. Hypothalamic neuroactivity in specific processes and central regulation of body temperature and water intake. BRAIN RESEARCH. BRAIN RESEARCH PROTOCOLS 2001; 8:68-73. [PMID: 11522529 DOI: 10.1016/s1385-299x(01)00089-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The method described was designed to elucidate the role of a particular neuronal system or specific nucleus in the central nervous system (CNS) in controlling physiological and biological functions. The neurochemical aspects of the CNS regulatory mechanism and related networks remain to be further investigated. There is little information available about the relationship between neuroactivity in the specific brain nuclei and physiological or biological responses in mammals. An adequate analysis of this relationship provides valuable insight to clarify which nucleus and what types of neurons are truly involved in the excitation of physiological events and its regulation. In the present study, we used microdialysis for stimulation of the anterior hypothalamus (AH) and simultaneous analysis of cholinergic activity, and we investigated c-Fos-like immunoreactivity (Fos-IR) in the brain in the same animal following microdialysis. The nuclear protein c-Fos, the product of c-fos oncogene, has been used as a marker of neuronal activity at the cellular level in the brain. Various physiological and pharmacological stimuli have been shown to induce Fos-IR in specific neuronal populations located in various regions of the brain. However, there are few studies investigating the responses produced by c-Fos expression in specific regions in same animals. We showed the involvement of hypothalamic cholinergic mechanisms in the thermoregulatory and water regulatory processes using the above procedures.
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Affiliation(s)
- A Takahashi
- Department of Neuropsychopharmacology (Tsumura), Gunma University School of Medicine, Maebashi, 371, Gunma, Japan.
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