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Dual Targeting Ligands-Histamine H 3 Receptor Ligands with Monoamine Oxidase B Inhibitory Activity-In Vitro and In Vivo Evaluation. Pharmaceutics 2022; 14:pharmaceutics14102187. [PMID: 36297622 PMCID: PMC9607599 DOI: 10.3390/pharmaceutics14102187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 10/03/2022] [Accepted: 10/09/2022] [Indexed: 11/17/2022] Open
Abstract
The clinical symptoms of Parkinson’s disease (PD) appear when dopamine (DA) concentrations in the striatum drops to around 20%. Simultaneous inhibitory effects on histamine H3 receptor (H3R) and MAO B can increase DA levels in the brain. A series of compounds was designed and tested in vitro for human H3R (hH3R) affinity and inhibitory activity to human MAO B (hMAO B). Results showed different activity of the compounds towards the two biological targets. Most compounds had poor affinity for hH3R (Ki > 500 nM), but very good inhibitory potency for hMAO B (IC50 < 50 nM). After further in vitro testing (modality of MAO B inhibition, permeability in PAMPA assay, cytotoxicity on human astrocyte cell lines), the most promising dual-acting ligand, 1-(3-(4-(tert-butyl)phenoxy)propyl)-2-methylpyrrolidine (13: hH3R: Ki = 25 nM; hMAO B IC50 = 4 nM) was selected for in vivo evaluation. Studies in rats of compound 13, in a dose of 3 mg/kg of body mass, confirmed its antagonistic effects for H3R (decline in food and a water consumption), decline in MAO B activity (>90%) in rat cerebral cortex (CTX), and an increase in DA content in CTX and striatum. Moreover, compound 13 caused a slight increase in noradrenaline, but a reduction in serotonin concentration in CTX. Thus, compound 13 is a promising dual-active ligand for the potential treatment of PD although further studies are needed to confirm this.
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Di Mauro P, Anzivino R, Distefano M, Borzì DD. Systemic mastocytosis: The roles of histamine and its receptors in the central nervous system disorders. J Neurol Sci 2021; 427:117541. [PMID: 34139449 DOI: 10.1016/j.jns.2021.117541] [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: 04/26/2021] [Revised: 06/10/2021] [Accepted: 06/11/2021] [Indexed: 11/28/2022]
Abstract
Mastocytosis is a rare disease of clonal hematological disorders characterized by a pathological accumulation of Mast Cells (MCs) in different tissues, with variable symptomatology and prognosis. Signs and symptoms of Systemic Mastocytosis (SM) are due to pathological infiltration of MCs and to the release of chemical mediators, mainly histamine. Patients with SM may also present with neurological symptoms or complications. The pathophysiology of these neurological disorders remains uncertain to this day, but it can be associated with the infiltration of tissue mastocytes, release of mastocytes' mediators or both. Moreover, there is a lot to understand about the role of neurological symptoms in SM and knowing, for example, what is the real frequency of neurological disorders in SM and if is present a relation between other SM subtypes, because it has been noted that the alteration of the histamine expression may be an initiating factor for susceptibility, gravity and progression of the epigenetic disease. In this review we explain the possible pathophysiological mechanism about neurological symptomatology found in some patients affected by SM, describing the role of histamine and its receptors in the nervous system and, in light of the results, what the future prospects may be for a more specific course of treatment.
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Affiliation(s)
- Paola Di Mauro
- Department of Medical and Surgical Sciences and Advanced Technologies "G.F. Ingrassia" A.O.U. "Policlinico - Vittorio Emanuele", University of Catania, Catania, Italy.
| | | | | | - Davide Domenico Borzì
- University of Catania, Italy and Italian Federation of Sports Medicine (FMSI), Rome, Italy
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Tarazona S, Carmona H, Conesa A, Llansola M, Felipo V. A multi-omic study for uncovering molecular mechanisms associated with hyperammonemia-induced cerebellar function impairment in rats. Cell Biol Toxicol 2021; 37:129-149. [PMID: 33404927 DOI: 10.1007/s10565-020-09572-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 11/12/2020] [Indexed: 12/01/2022]
Abstract
Patients with liver cirrhosis may develop covert or minimal hepatic encephalopathy (MHE). Hyperammonemia (HA) and peripheral inflammation play synergistic roles in inducing the cognitive and motor alterations in MHE. The cerebellum is one of the main cerebral regions affected in MHE. Rats with chronic HA show some motor and cognitive alterations reproducing neurological impairment in cirrhotic patients with MHE. Neuroinflammation and altered neurotransmission and signal transduction in the cerebellum from hyperammonemic (HA) rats are associated with motor and cognitive dysfunction, but underlying mechanisms are not completely known. The aim of this work was to use a multi-omic approach to study molecular alterations in the cerebellum from hyperammonemic rats to uncover new molecular mechanisms associated with hyperammonemia-induced cerebellar function impairment. We analyzed metabolomic, transcriptomic, and proteomic data from the same cerebellums from control and HA rats and performed a multi-omic integrative analysis of signaling pathway enrichment with the PaintOmics tool. The histaminergic system, corticotropin-releasing hormone, cyclic GMP-protein kinase G pathway, and intercellular communication in the cerebellar immune system were some of the most relevant enriched pathways in HA rats. In summary, this is a good approach to find altered pathways, which helps to describe the molecular mechanisms involved in the alteration of brain function in rats with chronic HA and to propose possible therapeutic targets to improve MHE symptoms.
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Affiliation(s)
- Sonia Tarazona
- Department of Applied Statistics, Operations Research and Quality, Universitat Politècnica de València, Valencia, Spain
| | - Héctor Carmona
- Department of Microbiology and Ecology, Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BioTecMed), Universidad de Valencia, Valencia, Spain
| | - Ana Conesa
- Microbiology and Cell Science Department, Institute for Food and Agricultural Research, University of Florida, Gainesville, FL, USA
- Genetics Institute, University of Florida, Gainesville, FL, USA
| | - Marta Llansola
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe, Eduardo Primo Yúfera, 3, 46012, Valencia, Spain.
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe, Eduardo Primo Yúfera, 3, 46012, Valencia, Spain
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Arafa NMS, Marie MAS, AlAzimi SAM. Effect of canagliflozin and metformin on cortical neurotransmitters in a diabetic rat model. Chem Biol Interact 2016; 258:79-88. [PMID: 27566243 DOI: 10.1016/j.cbi.2016.08.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 08/05/2016] [Accepted: 08/19/2016] [Indexed: 12/13/2022]
Abstract
BACKGROUND The rapid economic development in the Arabian Gulf has resulted in lifestyle changes that have increased the prevalence of obesity and type 2 diabetes, with the greatest increases observed in Kuwait. Dyslipidemia and diabetes are risk factors for disruptions in cortical neurotransmitter homeostasis. This study investigated the effect of the antidiabetic medications canagliflozin (CAN) and metformin (MET) on the levels of cortical neurotransmitters in a diabetic rat model. MATERIALS AND METHODS The rats were assigned to the control (C) group, the diabetic group that did not receive treatment (D) or the diabetic group treated with either CAN (10 mg/kg) or MET (100 mg/kg) for 2 or 4 weeks. Blood and urine glucose levels and cortical acetylcholinesterase (AChE) activity were assayed, and amino acid and monoamine levels were measured using HPLC. RESULTS The diabetic group exhibited a significant increase in AChE activity and a decrease in monoamine and amino acid neurotransmitter levels. In the CAN group, AChE was significantly lower than that in the D and D + MET groups after 2 weeks of treatment. In addition, a significant increase in some cortical monoamines and amino acids was observed in the D + MET and D + CAN groups compared with the D group. Histopathological analysis revealed the presence of severe focal hemorrhage, neuronal degeneration, and cerebral blood vessel congestion, with gliosis in the cerebrum of rats in the D group. The CAN-treated group exhibited severe cerebral blood vessel congestion after 2 weeks of treatment and focal gliosis in the cerebrum after 4 weeks of treatment. Focal gliosis in the cerebrum of rats in the MET-treated group was observed after 2 and 4 weeks of treatment. CONCLUSIONS We conclude that the effect of CAN and MET on neurotransmitters is potentially mediated by their antihyperglycemic and antihyperlipidemic effects. In addition, the effects of CAN on neurotransmitters might be associated with its receptor activity, and the effect of MET on neurotransmitters might be associated with cerebral metabolism.
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Affiliation(s)
- Nadia M S Arafa
- Faculty of Science, Biology Department, Jazan University, KSA & National Organization for Drug Control and Research, Department of Physiology, Egypt.
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Fogel WA, Stasiak A, Maksymowicz M, Kobos J, Unzeta M, Mussur M. Hepatocyte transplants improve liver function and encephalopathy in portacaval shunted rats. CNS Neurosci Ther 2014; 20:685-91. [PMID: 24716845 DOI: 10.1111/cns.12265] [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: 02/05/2014] [Revised: 03/10/2014] [Accepted: 03/11/2014] [Indexed: 11/28/2022] Open
Abstract
AIM Rats with portacaval shunt (PCS) are useful experimental models of human hepatic encephalopathy in chronic liver dysfunction. We have previously shown that PCS modifies amine neurotransmitter systems in the CNS and increases voluntary alcohol intake by rats. Hepatocyte transplantation, used in acute liver failure, has recently also been applied to chronic liver diseases, which prompted us to investigate whether the altered brain amine system and the drinking behavior in long-term shunted rats could be normalized by hepatocyte transplants. METHODS Hepatocytes, isolated from syngeneic donors by collagenase digestion, were injected (3 × 10(6) cells/rat) into the pancreatic tail region, 6 months after PCS. Hepatic function was evaluated by measuring urine urea and plasma L-histidine concentrations. A free choice test with two bottles (tap water and 10% ethyl alcohol) was performed for 3 days to assess the rats' preference for alcohol. The rats were euthanized 2 months posttransplantation. Brain histamine and 5-hydroxyindoleacetic acid (5-HIAA) levels were measured by radioenzymatic assay and by HPLC-EC, respectively, N-tele-methylhistamine by GC/MS while MAOA and MAOB activities by isotopic procedures. RESULTS Portacaval shunt rats with hepatocyte transplants gave more urea than before transplantation, with lower plasma L-His levels and higher body weight versus the PCS counterparts. Also, those rats consumed less alcohol. The CNS amines and 5-HIAA concentrations, as well as MAO-B activity, being abnormally high in untreated PCS rats, significantly reduced after PCS hepatocyte treatment. CONCLUSIONS The results support the therapeutic values of hepatocyte transplants in chronic liver diseases and the temporary character of PCS-exerted CNS dysfunctions.
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Palomero-Gallagher N, Zilles K. Neurotransmitter receptor alterations in hepatic encephalopathy: a review. Arch Biochem Biophys 2013; 536:109-21. [PMID: 23466244 DOI: 10.1016/j.abb.2013.02.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 02/18/2013] [Accepted: 02/19/2013] [Indexed: 01/07/2023]
Abstract
Hepatic encephalopathy (HE), a complex neuropsychiatric syndrome with symptoms ranging from subtle neuropsychiatric and motor disturbances to deep coma and death, is thought to be a clinical manifestation of a low-grade cerebral oedema associated with an altered neuron-astrocyte crosstalk and exacerbated by hyperammonemia and oxidative stress. These events are tightly coupled with alterations in neurotransmission, either in a causal or a causative manner, resulting in a net increase of inhibitory neurotransmission. Therefore, research focussed mainly on the potential role of γ-aminobutyric acid-(GABA) or glutamate-mediated neurotransmission in the pathophysiology of HE, though roles for other neurotransmitters (e.g. serotonin, dopamine, adenosine and histamine) or for neurosteroids or endogenous benzodiazepines have also been suggested. Therefore, we here review HE-related alterations in neurotransmission, focussing on changes in the levels of classical neurotransmitters and the neuromodulator adenosine, variations in the activity and/or concentrations of key enzymes involved in their metabolism, as well as in the densities of their receptors.
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Méndez M, Méndez-López M, López L, Aller MA, Arias J, Arias JL. Associative learning deficit in two experimental models of hepatic encephalopathy. Behav Brain Res 2008; 198:346-51. [PMID: 19056427 DOI: 10.1016/j.bbr.2008.11.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2008] [Revised: 11/04/2008] [Accepted: 11/09/2008] [Indexed: 01/26/2023]
Abstract
People with hepatic insufficiency can develop hepatic encephalopathy (HE), a complex neuropsychological syndrome covering a wide range of neurological and cognitive and motor alterations. The cognitive deficits include disturbances in intellectual functions such as memory and learning. In spite of its high prevalence in western societies, the causes of HE have not yet been clearly established. For this reason, experimental models of HE are used to study this condition. In this work, two experimental models were used, one Type B HE (portacaval shunt) and the other Type C HE (cirrhosis by intoxication with thioacetamide), to evaluate its effect on two tasks of associative learning: two-way active avoidance and step-through passive avoidance. The results show an impediment both in acquisition and retention of active avoidance in both models of HE. However, in passive avoidance, only the rats with portacaval shunt presented a memory deficit for the aversive event. In our opinion, these results can be explained by alterations in the neurotransmission system presented by animals with hepatic insufficiency, which are mainly caused by a rise in cerebral histamine and a dysfunction of the glutamatergic system.
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Affiliation(s)
- Marta Méndez
- Laboratorio de Neurociencias, Departamento de Psicología, Universidad de Oviedo, Plaza Feijoo s/n, 33003 Oviedo, Spain
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Abstract
Histamine is a transmitter in the nervous system and a signaling molecule in the gut, the skin, and the immune system. Histaminergic neurons in mammalian brain are located exclusively in the tuberomamillary nucleus of the posterior hypothalamus and send their axons all over the central nervous system. Active solely during waking, they maintain wakefulness and attention. Three of the four known histamine receptors and binding to glutamate NMDA receptors serve multiple functions in the brain, particularly control of excitability and plasticity. H1 and H2 receptor-mediated actions are mostly excitatory; H3 receptors act as inhibitory auto- and heteroreceptors. Mutual interactions with other transmitter systems form a network that links basic homeostatic and higher brain functions, including sleep-wake regulation, circadian and feeding rhythms, immunity, learning, and memory in health and disease.
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Affiliation(s)
- Helmut L Haas
- Institute of Neurophysiology, Heinrich-Heine-University, Duesseldorf, Germany.
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Abstract
A hypothesis about the inflammatory etiopathogeny mediated by astroglia of hepatic encephalopathy is being proposed. Three evolutive phases are considered in chronic hepatic encephalopathy: an immediate or nervous phase with ischemia-reperfusion, which is associated with reperfusion injury, edema and oxidative stress; an intermediate or immune phase with microglia hyperactivity, which produces cytotoxic cytokines and chemokines and is involved in enzyme hyperproduction and phagocytosis; and a late or endocrine phase, in which neuroglial remodeling, with an alteration of angiogenesis and neurogenesis, stands out. The increasingly complex trophic meaning that the metabolic alterations have in the successive phases making up this chronic inflammation could explain the metabolic regression produced in acute and acute-on-chronic hepatic encephalopathy. In these two types of hepatic encephalopathy, characterized by edema, neuronal nutrition by diffusion would guarantee an appropriate support of substrates, in accordance with the reduced metabolic needs of the cerebral tissue.
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Affiliation(s)
- Jorge-Luis Arias
- Psychobiology Laboratory, School of Psychology, University of Oviedo, Asturias, Spain
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Sergeeva OA, Schulz D, Doreulee N, Ponomarenko AA, Selbach O, Borsch E, Kircheis G, Huston JP, Häussinger D, Haas HL. Deficits in cortico-striatal synaptic plasticity and behavioral habituation in rats with portacaval anastomosis. Neuroscience 2005; 134:1091-8. [PMID: 16039790 DOI: 10.1016/j.neuroscience.2005.05.031] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2005] [Revised: 05/13/2005] [Accepted: 05/17/2005] [Indexed: 11/30/2022]
Abstract
Hepatic encephalopathy is characterized by disturbances of motor and cognitive functions involving the basal ganglia. So far no standards for assessment of neuropsychiatric abnormalities (disorders of sleep, mood, anxiety and personality) in subclinical hepatic encephalopathy have been defined. Using an animal model of mild (subclinical) hepatic encephalopathy we investigated now striatum-related behaviors and cortico-striatal synaptic plasticity in rats 2 months after introduction of a portacaval shunt and sham-operated matched controls. In a novel open field portacaval shunt rats displayed less locomotor activity; unlike controls they also showed no habituation to the field and no recall of the field environment after 24 h, indicative of cognitive deficit. The elevated-plus maze test indicated no differences in fear/anxiety in the portacaval shunt animals. Tetanic stimulation of cortical afferents in magnesium-free solution evoked an N-methyl-D-aspartate-dependent long-term potentiation in sham-operated animals. In portacaval shunt animals long-term potentiation was significantly impaired. Histamine, a potent modulator of cortico-striatal transmission, induced a larger long-term depression of field potentials in control compared with portacaval shunt rats. In conclusion, a combination of electrophysiological and behavioral approaches has revealed functional changes in cortico-striatal transmission. These data are relevant for understanding the mechanisms of motor and cognitive dysfunctions in hepatic encephalopathy patients and for the development of precise psychometric tests, evaluating cognitive deficits in subclinical hepatic encephalopathy.
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Affiliation(s)
- O A Sergeeva
- Department of Neurophysiology, Heinrich-Heine-Universität, Düsseldorf, Germany.
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Lozeva V, Montgomery JA, Tuomisto L, Rocheleau B, Pannunzio M, Huet PM, Butterworth RF. Increased brain serotonin turnover correlates with the degree of shunting and hyperammonemia in rats following variable portal vein stenosis. J Hepatol 2004; 40:742-8. [PMID: 15094220 DOI: 10.1016/j.jhep.2004.01.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2003] [Revised: 11/13/2003] [Accepted: 01/07/2004] [Indexed: 12/12/2022]
Abstract
BACKGROUND/AIMS Hepatic encephalopathy (HE) is a serious neuropsychiatric complication of chronic liver disease. Brain monoamines have been implicated in the pathogenesis of HE. We examined the relationship between monoamine dysfunction and the degree of portal-systemic shunting (PSS) in rats with varying degrees of PSS. METHODS Concentrations of catecholamines, serotonin, histamine, precursors and metabolites in frontal cortex of rats with varying degrees of PSS (9-99.8%) were measured by HPLC. RESULTS The concentrations of the serotonin precursor, tryptophan, and its metabolite, 5-HIAA were increased up to 4-fold in brains of rats with various degrees of PSS and were significantly correlated with the degree of shunting and with arterial ammonia levels. Brain levels of histamine, its precursor, l-histidine, and metabolite, tele-methylhistamine were significantly increased only following total shunting. Concentrations of catecholamines and their metabolites were not significantly correlated with degree of PSS or hyperammonemia. CONCLUSIONS Given the established role of the serotonin system in the regulation of sleep, circadian rhythmicity and locomotion these findings suggest that selective alterations of this system could be implicated in the pathogenesis of HE. Therapeutic approaches aimed at the normalization of serotonin turnover could be beneficial in the prevention and treatment of early neuropsychiatric symptoms of HE.
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Affiliation(s)
- Violina Lozeva
- Neuroscience Research Unit, Hopital Saint-Luc CHUM, 1058 St-Denis St., Montreal, Que., Canada H2X 3J4
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Lozeva V, Tuomisto L, Tarhanen J, Butterworth RF. Increased concentrations of histamine and its metabolite, tele-methylhistamine and down-regulation of histamine H3 receptor sites in autopsied brain tissue from cirrhotic patients who died in hepatic coma. J Hepatol 2003; 39:522-7. [PMID: 12971961 DOI: 10.1016/s0168-8278(03)00353-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
BACKGROUND/AIMS Hepatic encephalopathy (HE) is a serious neuropsychiatric complication of chronic liver disease. To determine whether changes in the central histaminergic system are a feature of human HE, we studied histamine, tele-methylhistamine, and presynaptic autoregulatory H(3) receptors in cerebral cortex and caudate-putamen obtained at autopsy from six cirrhotic patients and six appropriately matched controls. METHODS Histamine was assayed by HPLC; tele-methylhistamine by GC-MS. H(3) receptors were studied by in vitro receptor binding using [3H]R-alpha-methylhistamine as ligand. RESULTS In HE patients, there was a significant fourfold increase of histamine in caudate-putamen and a significant increase in all cortical regions studied. tele-Methyhistamine was also increased and the densities of histamine H(3) receptor sites were significantly decreased in patient material. CONCLUSIONS These findings are consistent with activation of the histaminergic system in HE. Given that histamine participates in the regulation of arousal and circadian rhythmicity, they indicate that induction of central histamine mechanisms may contribute to the development of neuropsychiatric symptoms, such as sleep disturbances and altered circadian rhythms in chronic HE and suggest that pharmacological manipulation of the histaminergic system could be beneficial in the treatment of HE in chronic liver failure.
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Affiliation(s)
- Violina Lozeva
- Neuroscience Research Unit, Centre Hospitalier de l'Université de Montréal, Hôpital Saint-Luc, 1058 St.-Denis St., Montreal, Quebec, Canada H2X 3J4
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Lozeva V, Tarhanen J, Attila M, Männistö PT, Tuomisto L. Brain histamine and histamine H3 receptors following repeated L-histidine administration in rats. Life Sci 2003; 73:1491-503. [PMID: 12865089 DOI: 10.1016/s0024-3205(03)00478-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In order to assess the importance of the chronic increase in precursor availability on central histaminergic mechanisms in rats, nine male Wistar rats received L-histidine orally at a dose of 1000 mg/kg, twice daily (07.00 h and 19.00 h) for 1 week; 9 rats were used as controls. Brain tissue histamine and tele-methylhistamine levels, as well as plasma histamine concentration were assayed. Binding properties and regional distribution of the autoregulatory histamine H3 receptors in brain were studied with [3H]-R-alpha-methylhistamine receptor binding and autoradiography. In L-histidine loaded rats, tissue histamine levels in cortex, hypothalamus, and rest of the brain were significantly increased by 40%-70%. Histamine concentrations in cerebellum and plasma, and tele-methylhistamine concentrations in cortex and hypothalamus did not change. The binding properties of H3 receptors in cortex were not altered. However, there were changes in the regional distribution of [3H]-R-alpha-methylhistamine binding sites, suggestive of a region-selective up-/down-regulation of histamine H3 receptors or their receptor sub-types. These results imply that following repeated L-histidine administration in the rat (1) there is enhanced synthesis of brain histamine not reflected in its functional release; (2) the excess of histamine is sequestered and stored rather than being metabolized; (3) histamine H(3) receptor binding properties are not altered, whereas receptor density is changed in selected regions. In conclusion, these results demonstrate that the neuronal mechanisms controlling histamine synthesis, storage, and release are adaptable and allow the sequestration of the excess of histamine in order to prevent excessively high neuronal activity.
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Affiliation(s)
- Violina Lozeva
- Department of Pharmacology and Toxicology, University of Kuopio, 70211 Kuopio, Finland.
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López L, González-Pardo H, Cimadevilla JM, Cavas M, Aller MA, Arias J, Arias JL. Cytochrome oxidase activity of the suprachiasmatic nucleus and pineal gland in rats with portacaval shunt. Exp Neurol 2002; 173:275-82. [PMID: 11822891 DOI: 10.1006/exnr.2001.7840] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Rhythmic behavioral and biochemical changes have been observed in both human and animal models with hepatic insufficiency. The basis of all these alterations is the principal endogenous pacemaker, the suprachiasmatic nucleus. The aim of this work, therefore, is to determine cytochrome c oxidase activity, a marker of neuronal activity and oxidative metabolism, in this nucleus in rats with portacaval shunt. In order to do this, this enzyme was histochemically marked and quantified by computer-assisted optical densitometry. Results show a reduced cytochrome oxidase activity in the suprachiasmatic nucleus in animals with portacaval shunts and, inversely, an increase in oxidative metabolism in the pineal gland, another circadian structure. However, the activity measured in a noncircadian brain structure, the hippocampus, which served as a control, showed no changes with surgery. Additionally, locomotor activity was assessed by actimeters and revealed a clearly reduced activity in animals with portacaval shunt. We conclude that the suprachiasmatic nucleus is possibly involved in the rhythmic changes associated with hepatic insufficiency.
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Affiliation(s)
- Laudino López
- Laboratorio de Psicobiología, Universidad de Oviedo, Oviedo, Spain
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15
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Anichtchik OV, Rinne JO, Kalimo H, Panula P. An altered histaminergic innervation of the substantia nigra in Parkinson's disease. Exp Neurol 2000; 163:20-30. [PMID: 10785440 DOI: 10.1006/exnr.2000.7362] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The central histaminergic system is one of the subcortical aminergic projection systems involved in several regulatory functions. The central dopaminergic and histaminergic systems interact extensively, but little is known about the histaminergic system in diseases affecting the dopaminergic neurons. The distribution of histaminergic fibers in the substantia nigra (SN) in postmortem brain samples from patients suffering from Parkinson's disease (PD) and normal controls was examined with a specific immunohistochemical method. Direct connections between dopaminergic neurones and histaminergic fibers were observed. Histamine in human SN was stored in fibers and varicosities. Sites of histamine formation were examined by l-histidine decarboxylase in situ hybridization. In both normal and PD brains HDC mRNA was found only in posterior hypothalamus and not in SN. The presence of histaminergic innervation of the human substantia nigra pars compacta (SNc) and reticulata (SNr), paranigral nucleus, radix of oculomotor nerve, and parabrachial pigmented nucleus was demonstrated. The density of histaminergic fibers in the middle portion of SNc and SNr was increased in brains with PD. In PD the morphology of histaminergic fibers was also altered; they were thinner than in controls and had enlarged varicosities. An increase of histaminergic innervation may reflect a compensatory event due to deficiency of, e.g., dopamine or a putative fiber growth inhibitory factor. Whether the changes seen in histaminergic fibers in PD are primary or secondary remains to be investigated.
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Affiliation(s)
- O V Anichtchik
- Department of Biology, Abo Akademi University, BioCity, Artillerigatan 6, Turku, 20520, Finland
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Abstract
Proton NMR chemical shift and J-coupling values are presented for 35 metabolites that can be detected by in vivo or in vitro NMR studies of mammalian brain. Measurements were obtained using high-field NMR spectra of metabolites in solution, under conditions typical for normal physiological temperature and pH. This information is presented with an accuracy that is suitable for computer simulation of metabolite spectra to be used as basis functions of a parametric spectral analysis procedure. This procedure is verified by the analysis of a rat brain extract spectrum, using the measured spectral parameters. In addition, the metabolite structures and example spectra are presented, and clinical applications and MR spectroscopic measurements of these metabolites are reviewed.
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Affiliation(s)
- V Govindaraju
- Department of Radiology, University of California San Francisco and DVA Medical Center, 4150 Clement St (114M), San Francisco, CA 94121, USA
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Vermathen P, Capizzano AA, Maudsley AA. Administration and (1)H MRS detection of histidine in human brain: application to in vivo pH measurement. Magn Reson Med 2000; 43:665-75. [PMID: 10800031 DOI: 10.1002/(sici)1522-2594(200005)43:5<665::aid-mrm8>3.0.co;2-3] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Measurement of histidine in vivo offers the potential for tissue pH measurement using routinely performed (1)H MR spectroscopy. In the brain, however, histidine concentrations are generally too low for reliable measurement. By using oral loading of histidine, this study demonstrates that brain concentrations can be significantly increased, enabling detection of histidine by localized (1)H MR measurements and making in vivo pH measurement possible. In studies carried out on healthy human subjects at 1.5 T, a consistent spectral quality downfield from water was achieved using a PRESS sequence at short echo times. Measurements at different TE values helped to characterize the downfield spectral region. Histidine loading of 400 mg/kg of body weight increased brain histidine levels by approximately 0.8 mM, with maximum histidine concentration reached 4 to 7 hr after consumption. The pH calculated from histidine resonances was 6.96, and a hyperventilation study demonstrated the potential for measuring altered pH.
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Affiliation(s)
- P Vermathen
- Department of Radiology, University of California, San Francisco, CA, USA
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18
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Lozeva V, Valjakka A, Lecklin A, Olkkonen H, Hippeläinen M, Itkonen M, Plumed C, Tuomisto L. Effects of the histamine H(1) receptor blocker, pyrilamine, on spontaneous locomotor activity of rats with long-term portacaval anastomosis. Hepatology 2000; 31:336-44. [PMID: 10655255 DOI: 10.1002/hep.510310212] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
To find out whether the changes in the brain histaminergic system are involved in the pathophysiology of portal-systemic encephalopathy, we examined the effects of histamine H(1) receptor blockade on spontaneous locomotor activity, feeding, and circadian rhythmicity in rats with portacaval anastomosis (PCA). Pyrilamine, an H(1) receptor blocker (15 mg/kg/day), was delivered with osmotic minipumps. Spontaneous locomotor activity was recorded for 72 hours in the open-field with an electromagnetic detector. Food intake was monitored twice daily at the end of the light (7 PM) and the dark (7 AM) phases for 3 days. Histamine H(1) receptor density in the suprachiasmatic nucleus (SCN) was examined with receptor autoradiography, employing [(3)H]pyrilamine. PCA surgery led to decreased movement time and velocity and flattened amplitude of the circadian rhythms of locomotion and feeding. In sham-operated rats, pyrilamine significantly decreased the movement time and velocity, as well as the total food consumption and completely abolished the circadian rhythmicity of locomotion. In contrast, pyrilamine increased the movement time and velocity in PCA-operated rats, particularly in the dark phase, and improved the precision of the circadian rhythms of locomotion and feeding. Histamine H(1) receptor density was not altered by PCA surgery, whereas pyrilamine treatment led to the complete blockade of H(1) receptors in both sham- and PCA-operated rats. We suggest that histaminergic imbalance has contributed to the generation and maintenance of the decreased spontaneous locomotor activity and altered circadian rhythmicity following PCA surgery in the rat, probably via an H(1) receptor-mediated mechanism.
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Affiliation(s)
- V Lozeva
- Department of Pharmacology, University Hospital of Kuopia, Finland
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19
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Lozeva V, Valjakka A, Anttila E, MacDonald E, Hippeläinen M, Tuomisto L. Brain histamine levels and neocortical slow-wave activity in rats with portacaval anastomosis. Hepatology 1999; 29:340-6. [PMID: 9918908 DOI: 10.1002/hep.510290204] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
To determine whether the increased histamine levels in the brain of rats with portacaval anastomosis (PCA) are associated with the development of sleep disturbances during the light phase, the neocortical slow-wave activity of PCA-operated rats was examined with electroencephalography (EEG) 1 month and 6 months after the surgery. The tissue levels of histamine, tele-methylhistamine, 5-hydroxytryptamine (5-HT) (serotonin), and 5-hydroxyindole-3-acetic acid (5-HIAA) in frontal cortex were assayed by high-performance liquid chromatography 6 months after the surgery. PCA surgery led to changes in the synchronized, low-frequency, high-amplitude frontal cortex EEG activity recorded during the light phase. Delta-wave amplitude but not delta time was significantly decreased, whereas both spindle amplitude and spindling time were significantly decreased. There were also significant age-related changes, presented as increases in the duration of spindles and the amplitude of both delta waves and spindles. PCA-operated rats showed a change in the pattern of EEG activity with increasing age similar to sham-operated rats. This suggests that once established, the resetting of the systems regulating the sleep-waking behavior is being maintained with time. The tissue levels of both histamine and metabolite in the frontal cortex were increased, whereas the serotonin system showed only an increase in the level of the metabolite. There was a significant negative correlation between the spindling time and the tissue histamine levels. We suggest that histamine, which participates in the control of vigilance, sleep, and wakefulness, as well as in the modulation of circadian rhythmicity, may play a role in the development of sleep disturbances in rats with PCA.
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Affiliation(s)
- V Lozeva
- Department of Pharmacology and Toxicology, University of Kuopio, Kuopio, Finland
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20
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Abstract
System-N transport plays an important role in l-glutamine uptake into isolated rat choroid plexus but its role in the transport of another System-N substrate, l-histidine, has yet to be determined. Similarly, the possible effects on System-N mediated l-histidine transport of changes in pH and extracellular l-glutamine, such as occur in cerebral ischemia and hepatic encephalopathy, have yet to be examined. In the absence of competing amino acids, l-[3H]histidine uptake in isolated rat choroid plexus was mediated by both Na+-independent and Na+-dependent transport. The former was inhibited by 2-amino-2-norbornane carboxlic acid, indicating System-L transport, while the latter appears System-N mediated as it was inhibited by three System-N substrates but not substrates for System-A and -ASC. The Na+-dependent uptake had a Km of 0.2 mM and a Vmax of 1.4 nmol/mg/min. It accounted for 30% of l-histidine uptake in the presence of physiological concentrations of amino acids. Reductions in pH markedly inhibited Na+-dependent but not Na+-independent transport indicating that, as in liver but not neurons, System-N mediated transport at the choroid plexus is pH sensitive. Increases in l-glutamine concentration in the pathophysiological range reduced l-histidine uptake via both System-L and -N.
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Affiliation(s)
- J Xiang
- Department of Surgery (Neurosurgery), University of Michigan, R5605 Kresge I, Ann Arbor, Michigan, MI 48109-0532, USA
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21
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Fogel WA, Kruk A, Kozlowska M, Sasiak K, Andrzejewski W, Maslinski C. Liver Regeneration Attenuates Increased Voluntary Alcohol Intake Evoked by the Liver Damage. Alcohol Clin Exp Res 1997. [DOI: 10.1111/j.1530-0277.1997.tb03830.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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22
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Fogel WA, Tuomisto L, Andrzejewski W, Sasiak K, Maslinski C. The effect of an ICV H3-agonist on plasma prolactin in portocaval shunted and sham operated rats. Inflamm Res 1996; 45 Suppl 1:S56-7. [PMID: 8696931 DOI: 10.1007/bf03354087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Affiliation(s)
- W A Fogel
- Institute of Biogenic Amines, Lodz, Poland
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23
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Valjakka A, Vartiainen J, Kosunen H, Hippeläinen M, Pesola P, Olkkonen H, Airaksinen MM, Tuomisto L. Histaminergic modulation of neocortical spindling and slow-wave activity in freely behaving rats. J Neural Transm (Vienna) 1996; 103:1265-80. [PMID: 9013413 DOI: 10.1007/bf01271187] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Histaminergic H3 receptor antagonists stimulate neuronal histamine release and could consequently have a number of physiological effects in the brain. The effects of H3 receptor blockade, induced by systemically administered thioperamide, were assessed on the frontal cortex electroencephalographic (EEG) properties in freely behaving rats. The relationship of EEG activity variables to endogenous brain histaminergic markers was also examined, both in controls and in portocaval anastomosis (PCA)-operated rats (which show increased levels of brain histamine and t-methylhistamine). Thioperamide reduced the incidence of thalamus-regulated EEG spindles, while it slightly increased their amplitude. It furthermore reduced the spectral power of low-frequency (1.5-5Hz) EEG, which effect was equally distributed over the spindle and non-spindle EEG states. These EEG effects were accompanied by increased motor activity of the animals. Both the low-frequency EEG activity and spindle incidence correlated inversely with the histamine level of the brain (hypothalamus and cerebellum excluded) while t-methylhistamine level correlated with the degree of thioperamide-induced reduction of slow-wave EEG activity. The present results provide evidence for the involvement of endogenous brain histamine level, histamine release (as assessed by t-methylhistamine level) and H3 receptors in the histaminergic regulation of neocortical synchronization patterns assumed to be linked to arousal control.
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Affiliation(s)
- A Valjakka
- Department of Pharmacology and Toxicology, University of Kuopio, Finland
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24
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Fogel WA, Tuomisto L, Andrzejewski W, Maslinski C. Portocaval shunt, an H3-antagonist and plasma hormone levels. Inflamm Res 1995; 44 Suppl 1:S52-3. [PMID: 8520999 DOI: 10.1007/bf01674392] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Affiliation(s)
- W A Fogel
- Institute of Biogenic Amines, Polish Academy of Sciences, Lodz
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25
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Lozeva V, MacDonald E, Belcheva A, Hippeläinen M, Kosunen H, Fogel A, Maslinski C, Tuomisto L. Long-term effects of portocaval anastomosis in rats on brain levels of histamine and methylhistamine. Inflamm Res 1995; 44 Suppl 1:S54-5. [PMID: 8521000 DOI: 10.1007/bf01674393] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Affiliation(s)
- V Lozeva
- Department of Pharmacology and Toxicology, University of Kuopio, Finland
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26
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Tuomisto J, Andrzejewski W, Unkila M, Pohjanvirta R, Linden J, Vartiainen T, Tuomisto L. Modulation of TCDD-induced wasting syndrome by portocaval anastomosis and vagotomy in Long-Evans and Han/Wistar rats. Eur J Pharmacol 1995; 292:277-85. [PMID: 7796867 DOI: 10.1016/0926-6917(95)90033-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Portocaval anastomosis and vagotomy operations were performed in Long-Evans (L-E) and Han/Wistar (H/W) rats to elucidate the mechanism of anorexia induced by TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin). TCDD-sensitive L-E rats were given a sublethal (5 micrograms/kg) or a lethal dose (20 micrograms/kg) by gavage 5-8 weeks after portocaval anastomosis. TCDD-resistant H/W rats were given a nonlethal dose (500 or 7200 micrograms/kg). The shunt operation did not reduce lethality from TCDD. The effect on wasting of the marginally toxic dose of 5 micrograms/kg in L-E rats was potentiated by the portocaval operation, and the lethal dose was effective in both shunted and sham-operated L-E rats. TCDD failed to decrease food intake and body weight in shunted rats of H/W strain at either dose level though it did so in sham-operated controls. The lack of effect may be due to the already reduced weight of shunted rats at the time of TCDD dosing. TCDD anorexia was not explained by changes in histamine or serotonin (5-HT) turnover in the brain. Vagotomy did not influence lethality after TCDD, although reduction in food intake was somewhat blunted in H/W rats. The results seem to indicate that the anorectic effect of TCDD is modified when portal blood bypasses the liver. The mechanisms remain to be elucidated in detail, but the results do not favor the role of liver as the only or the major initiator of TCDD anorexia. Little evidence was found to support a crucial role of vagal afferent input.
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Affiliation(s)
- J Tuomisto
- Department of Toxicology, National Public Health Institute, Kuopio, Finland
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27
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Fogel WA, Tuomisto L, Sasiak K, Rokicki W, Rokicki M, MacDonald E, Maslinski C. Histaminergic activity remains normal in portocaval shunted rats. Inflamm Res 1993. [DOI: 10.1007/bf01996481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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28
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Hypothalamic histamine and liver insufficiency. Inflamm Res 1992. [DOI: 10.1007/bf01997369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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29
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Tateishi K, Miura Y, Moriai O, Suzuki K, Takeichi N, Kobayashi H, Matsuoka Y, Sato S. Reduced somatostatin-like immunoreactivity in the brain of LEC rats with hepatic encephalopathy. REGULATORY PEPTIDES 1991; 36:131-9. [PMID: 1686662 DOI: 10.1016/0167-0115(91)90201-q] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Somatostatin-14-like immunoreactivity (S14LI) and somatostatin-28(1-12)-like immunoreactivity (S28(1-12)LI) in the brain of LEC (Long Evans Cinnamon) rats with hepatic encephalopathy were measured. Significant reduction of both S14LI and S28(1-12)LI was observed in the hypothalamus, medulla oblongata, striatum and spinal cord. Both of the immunoreactivities in the hypothalamus of these rats were approx. 50% of those in LEC rats without hepatic encephalopathy. The amounts of reduction of S14LI significantly correlated with those of reduction of S28(1-12)LI. No significant difference in gel chromatographic profiles of S14LI and S28(1-12)LI was observed between LEC rats with and without hepatic encephalopathy. These results suggest that the reduction of somatostatin-like immunoreactivity in LEC rats with hepatic encephalopathy may be caused by a decrease in production of prosomatostatin rather than altered degradation.
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Affiliation(s)
- K Tateishi
- First Department of Biochemistry, School of Medicine, Fukuoka University, Japan
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30
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Fogel WA, Andrzejewski W, Maslinski C. Liver damage, voluntary alcohol intake and brain histamine. AGENTS AND ACTIONS 1991; 33:150-3. [PMID: 1897432 DOI: 10.1007/bf01993152] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Liver dysfunction induced by protocaval anastomosis (PCA) in the rat is associated with a great reduction of hepatic alcohol and aldehyde dehydrogenase activities. Despite this, PCA rats voluntarily drank more alcohol than unoperated rats. When subjected to forced alcohol consumption, shunted rats maintained their exaggerated voluntary alcohol intake whereas unoperated rats developed aversion to alcohol. Hypothalamic levels of both histamine and histidine were very high in PCA rats. When these rats were chronically exposed to alcohol, there was a slight decrease in hypothalamic histidine concentration and consequently a lower histamine content. Chronic exposure to alcohol did not, however, influence hypothalamic tissue levels of histamine or histidine in unoperated rats. In both groups, chronic alcohol treatment exerted a stimulatory effect on hepatic alcohol metabolizing enzymes.
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Affiliation(s)
- W A Fogel
- Department of Biogenic Amines, Polish Academy of Sciences, Lodz
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31
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Castrén E, Panula P. The distribution of histidine decarboxylase mRNA in the rat brain: an in situ hybridization study using synthetic oligonucleotide probes. Neurosci Lett 1990; 120:113-6. [PMID: 2293080 DOI: 10.1016/0304-3940(90)90181-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
L-Histidine decarboxylase catalyzes the formation of histamine from the amino acid L-histidine. We have studied the distribution of neurons expressing mRNA for histidine decarboxylase in adult rat brain using in situ hybridization with synthetic oligonucleotide probes. The expression of mRNA for histidine decarboxylase was detected in the hypothalamic tuberomammillary nucleus that has been shown to contain histidine decarboxylase-like and histamine-like immunoreactivity, but not in any other brain area. This method may prove useful in studying the physiological role of central histaminergic neurons.
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Affiliation(s)
- E Castrén
- Department of Anatomy, University of Helsinki, Finland
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