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Hippocampal histamine receptors and conflictive exploration in the rat: studies using the elevated asymmetric plus-maze
Ruarte, M.B.;Orofino, A.G.;Alvarez, E.O.;
Brazilian Journal of Medical and Biological Research , 1997, DOI: 10.1590/S0100-879X1997001200012
Abstract: the possible role of histamine receptors in the hippocampal formation on the exploratory motivation and emotionality of the rat was studied. an elevated asymmetric plus-maze composed of 4 different arms (no walls, single high wall, high and low walls and two high walls) arranged at 90o angles was used. the exploration score, considered to be an index of exploratory motivation, and the permanency score, considered to be an index of emotionality (anxiety), were determined. histamine was administered locally into the ventral hippocampus at three different doses (9, 45 and 90 nmol). another group of rats was also microinjected with 45 nmol of pyrilamine (a histamine h1 receptor antagonist) or ranitidine (a histamine h2 receptor antagonist) in addition to 9 nmol of histamine in order to identify the possible type of histamine receptor involved. histamine administration significantly inhibited the exploration score and increased the permanency score at the doses of 9 and 45 nmol in two of four arms. these effects were completely blocked by the administration of either histamine receptor antagonist. the present results suggest that in the hippocampal formation histamine inhibits exploratory motivation and decreases emotionality by activating both types of histamine receptors. also, the elevated asymmetric plus-maze appears to be a suitable technique to quantify exploration and possibly" anxiety"
Hippocampal histamine receptors and conflictive exploration in the rat: studies using the elevated asymmetric plus-maze  [cached]
Ruarte M.B.,Orofino A.G.,Alvarez E.O.
Brazilian Journal of Medical and Biological Research , 1997,
Abstract: The possible role of histamine receptors in the hippocampal formation on the exploratory motivation and emotionality of the rat was studied. An elevated asymmetric plus-maze composed of 4 different arms (no walls, single high wall, high and low walls and two high walls) arranged at 90o angles was used. The exploration score, considered to be an index of exploratory motivation, and the permanency score, considered to be an index of emotionality (anxiety), were determined. Histamine was administered locally into the ventral hippocampus at three different doses (9, 45 and 90 nmol). Another group of rats was also microinjected with 45 nmol of pyrilamine (a histamine H1 receptor antagonist) or ranitidine (a histamine H2 receptor antagonist) in addition to 9 nmol of histamine in order to identify the possible type of histamine receptor involved. Histamine administration significantly inhibited the exploration score and increased the permanency score at the doses of 9 and 45 nmol in two of four arms. These effects were completely blocked by the administration of either histamine receptor antagonist. The present results suggest that in the hippocampal formation histamine inhibits exploratory motivation and decreases emotionality by activating both types of histamine receptors. Also, the elevated asymmetric plus-maze appears to be a suitable technique to quantify exploration and possibly" anxiety"
In Vivo Histamine Optical Nanosensors  [PDF]
Kevin J. Cash,Heather A. Clark
Sensors , 2012, DOI: 10.3390/s120911922
Abstract: In this communication we discuss the development of ionophore based nanosensors for the detection and monitoring of histamine levels in vivo. This approach is based on the use of an amine-reactive, broad spectrum ionophore which is capable of recognizing and binding to histamine. We pair this ionophore with our already established nanosensor platform, and demonstrate in vitro and in vivo monitoring of histamine levels. This approach enables capturing rapid kinetics of histamine after injection, which are more difficult to measure with standard approaches such as blood sampling, especially on small research models. The coupling together of in vivo nanosensors with ionophores such as nonactin provide a way to generate nanosensors for novel targets without the difficult process of designing and synthesizing novel ionophores.
HISTAMINE BIOSENSOR: A REVIEW
Niraj*, M. M. Gupta and Shweta Pandey
International Journal of Pharmaceutical Sciences and Research , 2012,
Abstract: Some biogenic amine like Histamine, cadaverine and putrescine have been confirmed as useful chemical indicators to estimate bacterial spoilage of foods, particularly fish and fish products, cheese, meat and fermented foods. Histamine is toxic at high intakes, while cadaverine and putrescine potentiate the effects of Histamine. Histamine has regulated level of 200 mg/kg (200 ppm). Basic principle involved in Biogenic amines biosensor is the action of diamine oxidase (DAO) that catalyzes the oxidative deamination of primary amines to the corresponding aldehydes, hydrogen peroxide and ammonia. Two different approaches for the histamine biosensor design were studied, i.e. the enzyme DAO was directly immobilized on the surface of the oxygen electrode membrane using glutaraldehyde or entrapped in a hydrogel film. In histamine biosensor consisting of diamine oxidase (DAO) and a conventional oxygen electrode transducer was developed and applied for the determination of standard histamine solutions. For immobilisation with glutaraldehyde, the enzyme was cross-linked with glutaraldehyde as a bifunctional reagent on the electrode surface. For entrapment, DAO was entrapped in a polymeric hydrogel film, i.e. poly(hydroxyl ethyl methacrylate) (pHEMA) polymer and deposited onto the teflon membrane of the oxygen electrode. Good linear correlation response obtained of the histamine biosensors with immobilized DAO showed between the changes of oxygen level with changes in concentration of histamine at both high concentration ranges (200-1000 mg/L) and low concentrations (20-100 mg/L). However, the sensitivity of the biosensor response decreased at high concentration range of histamine, for the direct DAO immobilisation with glutaraldehyde. Biogenic amines concentration can be measured by monitoring either the decrease in oxygen or the increase of hydrogen peroxide concentration.
Histamine modulates microglia function
Raquel Ferreira, Tiago Santos, Joana Gon?alves, Gra?a Baltazar, Lino Ferreira, Fabienne Agasse, Liliana Bernardino
Journal of Neuroinflammation , 2012, DOI: 10.1186/1742-2094-9-90
Abstract: Firstly, we detected the expression of all known histamine receptor subtypes (H1R, H2R, H3R and H4R), using a murine microglial cell line and primary microglia cell cultures from rat cortex, by real-time PCR analysis, immunocytochemistry and Western blotting. Then, we evaluated the role of histamine in microglial cell motility by performing scratch wound assays. Results were further confirmed using murine cortex explants. Finally, interleukin-1beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) levels were evaluated by ELISA measurements to determine the role of histamine on the release of these inflammatory mediators.After 12 h of treatment, 100 μM histamine and 10 μg/ml histamine-loaded poly (lactic-co-glycolic acid) microparticles significantly stimulated microglia motility via H4R activation. In addition, migration involves α5β1 integrins, and p38 and Akt signaling pathways. Migration of microglial cells was also enhanced in the presence of lipopolysaccharide (LPS, 100 ng/ml), used as a positive control. Importantly, histamine inhibited LPS-stimulated migration via H4R activation. Histamine or H4R agonist also inhibited LPS-induced IL-1β release in both N9 microglia cell line and hippocampal organotypic slice cultures.To our knowledge, we are the first to show a dual role of histamine in the modulation of microglial inflammatory responses. Altogether, our data suggest that histamine per se triggers microglia motility, whereas histamine impedes LPS-induced microglia migration and IL-1β release. This last datum assigns a new putative anti-inflammatory role for histamine, acting via H4R to restrain exacerbated microglial responses under inflammatory challenge, which could have strong repercussions in the treatment of CNS disorders accompanied by microglia-derived inflammation.
OCCURANCE OF HISTAMINE IN FISH PRODUCTS ON MARKET  [cached]
R. Mancusi,R.M. Bini,M. Cecchini,G. Delle Donne
Italian Journal of Food Safety , 2012, DOI: 10.4081/ijfs.2012.3.35
Abstract: Histamine fish poisoning is quite common and occur in consequence of microbial decarboxylase whose activity begin early in the post-mortem but are triggered in consequence of abuse in the shelf life of fish products. In this study forty-eight samples of tuna, mackerel, anchovies, sardines, fresh or processed were sampled from fish shops and supermarkets in the City of Bologna in the period from January to July 2010. Concentration of histamine was assessed using ELISA quantitative test and presence of psicrotrophic histamine forming bacteria was searched using a modified Niven agar medium which allow detection of suspect colonies that were confirmed by PCR for detecting the presence of the histidine decarboxylase genes in their DNA. The positive colonies were then identified on the basis of their morphology, Gram reaction and biochemical characteristics with API20E. The differential capability of the Niven agar was found to be low and approximately one fifth of the suspect colonies were confirmed by the PCR test, which however included both strong and weak histamine producing strains. The presence of Morganella morganii was associated with concentration of histamine 460 mg kg-1 above the allowed limit in a sample of tuna sampled from a fish shop. The same bacterium was found in samples of Atlantic horse mackerel (Trachurus trachurus). High histamine concentration (between 258 and > 300 mg kg-1) were observed in salted European pilchard and European anchovy (228 mg kg-1) sold loose in supermarkets. Because temperature abuse could occur when Tuna (fresh/defrozen) are hold on chopping board to sell fresh cuts and during shelf life of salted pilchard and pickled anchovies held in opened cans in chilled display cabinets for extended period, which might results in very high histamine concentration, controls on time and temperature at the retail, in addition to those done during the harvest and processing are needed. The studies aiming at quantitatively assess the prevalence and number of histamine producing bacteria in fish products that were not involved in histamine poisoning cases and/or do not show high level of histamine are rather complex , requiring many tests for confirming the histamine forming ability of the suspect isolated strains and further studies are needed to develop techniques for enumerating the histamine producing bacteria.
Histamine Formation and Its Control in Cheese: A Review
K Ekici,H. Coskun,T. Sienkiewicz
Journal of Food Technology , 2013,
Abstract: Histamine is one of the biogenic amine formed in the biological systems. Histamine is formed in fishes such as tuna and in the ripened cheeses. Fresh milk contains histamine in a low amount (<0.3) while cheeses may have the amount as high as 2500 ppm. Histamine content of the cheeses is affected by many factors. Ingestion of 70-1000 mg of histamine in a single meal is necessary to elicit any symptoms of toxicity. Histamine poisoning shows symptoms of rash, urticario, edema, and localized inflammation affect the cutareous system; nausea, vomiting, diarrhea, and abdominal cramps in gastrointestinal track. Hypotension, headache, palpitations, tingling, flushing and burning sensations in the mouth are the other symptoms. Different biogenic amines are predominant in different kind of cheeses. HPLC, gas-liquid chromatography and TLC are used to determine bigenic amines. Many enzymatic methods including enzymelinked immunosorbent assay (ELISA) have been developed to detect histamine in blood and tissues.
Histamine index and clinical expression of rheumatoid arthritis activity  [PDF]
Tomi?-Lu?i? Aleksandra P.,Pantovi? Suzana B.,Rosi? Gvozden L.,Obradovi? Zdravko M.
Vojnosanitetski Pregled , 2010, DOI: 10.2298/vsp1004286t
Abstract: Background/Aim. Many arguments prove the pathophysiologic role of histamine in the process of remodeling and joint destruction in rheumatoid arthritis. The aim of our study was to find out if there was a relation between histamine concentration in synovial fluid and blood with clinical expression of disease activity. Methods. Histamine concentration in synovial fluid and blood was determinated in 19 patients with rheumatoid arthritis. Histamine concentration measurement was based on the Shore's fluorometric method. Histamine index (HI) was evaluated as a ratio between histamine concentration in synovial fluid and blood. Disease activity score, DAS 28 (3), with three variables (erythrocyte sedimentation rate, the number of swelled joints and the number of tender joints) was also evaluated. Results. Our results showed that there was no significant difference in concentration of histamine in synovial fluid and blood related to disease activity. However, there was a significant difference in the histamine index which was increased proportionally with disease activity. Conclusion. Our study indicates that histamine index could be useful in estimation of rheumatoid arthritis activity.
Persistent Histamine Excitation of Glutamatergic Preoptic Neurons  [PDF]
Iustin V. Tabarean
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0047700
Abstract: Thermoregulatory neurons of the median preoptic nucleus (MnPO) represent a target at which histamine modulates body temperature. The mechanism by which histamine excites a population of MnPO neurons is not known. In this study it was found that histamine activated a cationic inward current and increased the intracellular Ca2+ concentration, actions that had a transient component as well as a sustained one that lasted for tens of minutes after removal of the agonist. The sustained component was blocked by TRPC channel blockers. Single-cell reverse transcription-PCR analysis revealed expression of TRPC1, TRPC5 and TRPC7 subunits in neurons excited by histamine. These studies also established the presence of transcripts for the glutamatergic marker Vglut2 and for the H1 histamine receptor in neurons excited by histamine. Intracellular application of antibodies directed against cytoplasmic sites of the TRPC1 or TRPC5 channel subunits decreased the histamine-induced inward current. The persistent inward current and elevation in intracellular Ca2+ concentration could be reversed by activating the PKA pathway. This data reveal a novel mechanism by which histamine induces persistent excitation and sustained intracellular Ca2+ elevation in glutamatergic MnPO neurons.
Nα-Urocanylhistamine: A Natural Histamine Derivative  [PDF]
Paul W. Baures,Karupaiyan Kaliyan,John Desper
Molecules , 2002, DOI: 10.3390/71100813
Abstract: Nα-Urocanylhistamine and two related compounds were synthesized by using PyBOP coupling protocols. These compounds represent naturally occurring histamine derivatives.
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