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Histamine Concentration (histamine + concentration)
Selected AbstractsEFFECT OF STORAGE TEMPERATURE ON HISTAMINE FORMATION IN SARDINA PILCHARDUS AND ENGRAULIS ENCRASICOLUS AFTER CATCHJOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2007PIERINA VISCIANO ABSTRACT Histamine formation in Sardina pilchardus and Engraulis encrasicolus as a function of storage temperature was studied. Fish were caught off the Adriatic Coast and were carried immediately to the laboratory. A portion of dorsal muscle from each fish was soon analyzed, while two other portions were examined after storage at two different temperatures (25 and 4C) for 24 and 72 h, respectively. The analyses were carried out by high-performance liquid chromatography (HPLC)-UV and confirmed by HPLC-diode array detector. Histamine concentrations were always higher than the European Community admissible levels in samples stored at 25C. In fish stored at 4C, histamine was detected only in E. encrasicolus. PRACTICAL APPLICATIONS Time experiments were conducted to quantify the histamine formation in scombroid species at two different temperatures. The first assay (24 h, 25C) could reproduce the modality of sale adopted by fishermen or retailers in summer on the one hand, and the maintenance at ambient temperature of semipreserved sardines or anchovies during salting and ripening on the other hand. The second experiment (72 h, 4C) was based on the domestic cold preservation of fish before the consumption, which sometimes occurs some days after purchasing. Even if ice storage is recommended, time/temperature abuse conditions often occur in the fish merchandising chain. The results of this research showed that high histamine concentrations could be found in the analyzed species not only at an abused temperature, but also at a common storage temperature of fish at home. [source] Histamine induces neural stem cell proliferation and neuronal differentiation by activation of distinct histamine receptorsJOURNAL OF NEUROCHEMISTRY, Issue 2 2008Anayansi Molina-Hernández Abstract Histamine has neurotransmitter/neuromodulator functions in the adult brain, but its role during CNS development has been elusive. We studied histamine effects on proliferation, cell death and differentiation of neuroepithelial stem cells from rat cerebral cortex in vitro. RT-PCR and Western blot experiments showed that proliferating and differentiated cells express histamine H1, H2 and H3 receptors. Treatments with histamine concentrations (100 nM,1 mM) caused significant increases in cell numbers without affecting Nestin expression. Cell proliferation was evaluated by BrdU incorporation; histamine caused a significant increase dependent on H2 receptor activation. Apoptotic cell death during proliferation was significantly decreased at all histamine concentrations, and cell death was promoted in a concentration-dependent manner by histamine in differentiated cells. Immunocytochemistry studies showed that histamine increased 3-fold the number of neurons after differentiation, mainly by activation of H1 receptor, and also significantly decreased the glial (astrocytic) cell proportion, when compared to control conditions. In summary, histamine increases cell number during proliferative conditions, and has a neuronal-differentiating action on neural stem cells, suggesting that the elevated histamine concentration reported during development might play a role in cerebrocortical neurogenesis, by activation of H2 receptors to promote proliferation of neural precursors, and favoring neuronal fate by H1 -mediated stimulation. [source] Skin reactivity to histamine and to allergens in unselected 9-year-old children living in Poland and ItalyPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 3 2003Roberto Ronchetti Several studies have shown a higher prevalence of positive skin-prick tests to airborne allergens in Western than in Eastern European countries. We have recently reported that skin histamine reactivity significantly increased in Italy over the past 15 years. Population differences in skin histamine reactivity could, at least in part, explain the reported differences in positive allergen skin tests. To test this hypothesis we compared histamine skin reactivity and the prevalence of allergen positive skin-prick tests in a sample of Italian and Polish schoolchildren. A total of 336 unselected 9-year-old-schoolchildren (198 in Italy and 138 in Poland) underwent skin-prick tests with three different histamine concentrations (10, 1 and 0.2 mg/ml) and with a panel of common airborne allergens according to the ISAAC protocol, phase two. Mean wheals elicited by skin-prick tests with the three serial concentrations of histamine were significantly larger (p < 0.001) and shifted more toward higher values (p < 0.001) in Italian than in Polish children. The differences were greater for the intermediate histamine concentration tested (1 mg/ml) than for the highest concentration (10 mg/ml). Skin-prick tests for airborne allergens were more frequently positive in Italian children: wheals ,,3 mm induced by any allergen [odds ratio (OR) 1.69; confidence interval (CI) 0.98,2.92] by Dermatophagoides pteronyssinus (OR 1.92; CI 0.97,3.80) and by D. farinae (OR 3.15; CI 1.16,8.63). Labeling as positive allergen wheal reactions half the size of the 10 mg/ml histamine wheal or larger reduced but did not abolish the Italian,Polish differences. The significantly higher skin histamine reactivity observed in Italian children could help to explain why allergen skin-test reactions differ in the East and West European populations. Moreover, differences in nonallergen-specific factors among populations should be considered in the interpretation of skin test results (e.g. cut-off points). To obtain meaningful results, epidemiological studies of allergies should include serial histamine dilutions. [source] Assessment of inhaled corticosteroid treatment response in asthma using hypertonic histamine challenge-induced coughTHE CLINICAL RESPIRATORY JOURNAL, Issue 2 2010Minna Purokivi Abstract Background and Aims:, Bronchial provocation tests may be utilised to monitor the efficacy of the corticosteroid treatment. Unfortunately, these measurements necessitate good patient cooperation during the spirometry. Coughing during such tests is related to the degree of the bronchoconstriction and occurs involuntarily, i.e. independent of patient cooperation. This study aimed to evaluate the utility of a hypertonic histamine challenge-induced cough in assessing the efficacy of inhaled corticosteroid treatment. Methods:, A total of 16 steroid-naďve asthmatics and 10 non-asthmatic, symptomatic controls received 800-µg beclomethasone (Beclomet Easyhaler®, Orion Ltd., Orion Pharma, Helsinki, Finland) via powder inhaler per day for 8 weeks. Videoed inhalation challenge with hypertonic histamine solution was performed before and after the treatment. Symptom questionnaire was completed before both challenges. The airway responsiveness to hypertonic histamine was expressed as the cumulative number of coughs divided by the final histamine concentration administered [coughs/concentration ratio (CCR)] and as the provocative concentration of histamine to induce a 20% fall in FEV1(PC20). Results:, CCR [geometric mean; 95% confidence interval (CI)] of the asthmatic subjects decreased from 494 (209,1168) to 73.6 (29.8,182) coughs per mg/mL (P = 0.002). Their PC20 levels were 1.31 (1.07,1.60) and 1.91 (1.33,2.74) mg/mL over the treatment period (P = 0.01). The symptom frequency also decreased significantly in the asthmatics (P = 0.039). There were no significant changes in PC20 level, in CCR level or in symptom frequency in non-asthmatic subjects during the treatment. Conclusions:, Hypertonic histamine challenge-induced cough and PC20 are sensitive measures in assessing the treatment effect in asthma. The cough response may be especially useful in subjects who cannot perform spirometry reliably. Please cite this paper as: Purokivi M, Koskela H, Koistinen T, Peuhkurinen K and Kontra KM. Assessment of inhaled corticosteroid treatment response in asthma using hypertonic histamine challenge-induced cough. The Clinical Respiratory Journal 2010; 4: 67,73. [source] Cholinergic responses of ileal longitudinal muscle under short-lasting exposure to cupric ionsAUTONOMIC & AUTACOID PHARMACOLOGY, Issue 1 2008Ch. Nachev Summary 1 The effect of short-term exposure to cupric ions (Cu2+) on electric field-stimulated (EFS) or agonist-induced contractions of guinea-pig isolated ileum was studied. 2 EFS elicited tetrodotoxin- and atropine-sensitive contractions that were concentration dependently inhibited by Cu2+ (IC50 = 14.7 ± 4.2 ,m). Maximal inhibition (90.4 ± 3.1% of baseline contractions) was attained with 30 ,m Cu2+. 3 Carbachol induced concentration-dependent contractions (EC50 = 0.021 ± 0.004 ,m) that were inhibited by 0.3 ,m atropine to a non-competitive manner (decreased maximal response, EC50 value = 0.26 ± 0.04 ,m, Ke = 0.026 ,m). Cu2+ (15 ,m) potentiated contractions induced by carbachol, such that the maximum response was increased by 30.3 ± 10.4%. 4 Histamine induced concentration-dependent contractions of the longitudinal muscle (EC50 = 0.11 ± 0.03 ,m). Dyphenhydramine (0.1 ,m) decreased the maximum response to histamine and shifted the curve to the right (EC50 value = 4.71 ± 0.35 ,m, Ke = 0.0024 ,m). Cu2+ (15 ,m) caused a rightward shift of the histamine concentration,response curve (EC50 = 0.61 ± 0.1 ,m) without changing the maximum response. Serotonin induced concentration-dependent contractions at concentrations higher than 10 nM (EC50 value of 0.34 ± 0.12 ,m) were not significantly affected by 15 ,m Cu2+. 5 Our results suggest that in ileal longitudinal muscle, Cu2+ inhibits cholinergic neurotransmission but also facilitates postsynaptic muscarinic receptor responses. [source] ECL Cell Histamine Mobilization Studied byGastric Submucosal Microdialysis in Awake Rats:Methodological ConsiderationsBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2003Peter Ericsson They secrete histamine in response to circulating gastrin. Gastric submucosal microdialysis has been used to study ECL-cell histamine mobilization in awake rats. In the present study we assess the usefulness and limitations of the technique. Microdialysis probes were implanted in the gastric submucosa. Histological analysis of the stomach wall around the probe revealed a moderate, local inflammatory reaction 1,2 days after implantation; the inflammation persisted for at least 10 days. Experiments were conducted 3 days after the implantation. The "true" submucosal histamine concentration was determined by perfusing at different rates (the zero flow method) or with different concentrations of histamine at a constant rate (the no-net-flux method): in fasted rats it was calculated to be 87±5 (means±S.E.M.) nmol/l and 76±9 nmol/l, respectively. The corresponding histamine concentrations in fed rats were 93±5 and 102±8 nmol/l, respectively. With a perfusion rate of 74 ,l/hr the recovery of submucosal histamine was 49%, at 34 ,l/hr the recovery increased to 83%. At a perfusion rate below 20 ,l/hr the microdialysate histamine concentration was close to the actual concentration in the submucosa. The ECL-cell histamine mobilization was independent of the concentrations of Ca2+ in the perfusion medium (0,3.4 mmol/l Ca2+). In one experiment, histamine mobilization in response to gastrin (10 nmol/kg/hr subcutaneously) was monitored in rats pretreated with prednisolone (60 mg/kg) or indomethacin (15 mg/kg). The two antiinflammatory agents failed to affect the concentration of histamine in the microdialysate either before or during the gastrin challenge, which was in accord with the observation that the inflammatory reaction was modest and that inflammatory cells were relatively few around the probe and in the wall of the probe. In another experiment, rats were given aminoguanidine (10 mg/kg) or metoprine (10 mg/kg) 4 hr before the start of gastrin infusion (5 nmol/kg/hr intravenously). Metoprine (inhibitor of histamine N-methyl transferase) did not affect the microdialysate histamine concentration, while aminoguanidine (inhibitor of diamine oxidase) raised both basal and gastrin-stimulated histamine concentrations. We conclude that microdialysis can be used to monitor changes in the concentration of histamine in the submucosa of the stomach, and that the inflammatory reaction to the probe is moderate and does not affect the submucosal histamine mobilization. [source] Effects of sepsis on mast cells in rat dura mater: influence of L -NAME and VIPBRITISH JOURNAL OF PHARMACOLOGY, Issue 7 2001F Tore The influence of lipopolysaccharide (LPS)-induced sepsis on the various mast cell phenotypes of rat dura mater were examined both by immunohistochemical and biochemical methods. Three different populations of mast cells were identified in control rats: connective tissue type mast cells (CTMC) which contain rat mast cell protease1 (RMCP1), histamine, serotonin and heparin, mucosal type mast cells (MMC) which contain RMCP2, histamine and serotonin, and intermediate type which contains both RMCP1 and RMCP2 and probably various proportions of amines and heparin. LPS (25 mg kg,1 i.p.) caused changes in the proportions of the various types of mast cells. The number of MMC and intermediate type mast cells significantly increased and the number of mast cells immunopositive for both heparin and serotonin significantly decreased. Biochemical analysis showed that the histamine concentration of dura increased while its serotonin concentration decreased. While vasoactive intestinal peptide (VIP) (25 ng kg,1 i.p.) appears to potentiate LPS effects on dura mater mast cells, non-selective inhibition of nitric oxide (NO) synthase by Ng -nitro- L -arginine methyl ester (L -NAME) (30 mg kg,1 i.p.) did not influence sepsis-induced mast cell changes. These findings suggest that mast cells of dura mater may play a role in brain protection during sepsis. British Journal of Pharmacology (2001) 134, 1367,1374; doi:10.1038/sj.bjp.0704412 [source] EFFECT OF STORAGE TEMPERATURE ON HISTAMINE FORMATION IN SARDINA PILCHARDUS AND ENGRAULIS ENCRASICOLUS AFTER CATCHJOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2007PIERINA VISCIANO ABSTRACT Histamine formation in Sardina pilchardus and Engraulis encrasicolus as a function of storage temperature was studied. Fish were caught off the Adriatic Coast and were carried immediately to the laboratory. A portion of dorsal muscle from each fish was soon analyzed, while two other portions were examined after storage at two different temperatures (25 and 4C) for 24 and 72 h, respectively. The analyses were carried out by high-performance liquid chromatography (HPLC)-UV and confirmed by HPLC-diode array detector. Histamine concentrations were always higher than the European Community admissible levels in samples stored at 25C. In fish stored at 4C, histamine was detected only in E. encrasicolus. PRACTICAL APPLICATIONS Time experiments were conducted to quantify the histamine formation in scombroid species at two different temperatures. The first assay (24 h, 25C) could reproduce the modality of sale adopted by fishermen or retailers in summer on the one hand, and the maintenance at ambient temperature of semipreserved sardines or anchovies during salting and ripening on the other hand. The second experiment (72 h, 4C) was based on the domestic cold preservation of fish before the consumption, which sometimes occurs some days after purchasing. Even if ice storage is recommended, time/temperature abuse conditions often occur in the fish merchandising chain. The results of this research showed that high histamine concentrations could be found in the analyzed species not only at an abused temperature, but also at a common storage temperature of fish at home. [source] BACTERIAL FORMATION OF HISTAMINE IN JACK MACKEREL (TRACHURUS SYMMETRICUS)JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2004A. BERMEJO ABSTRACT Peak histamine concentrations of 0.023, 0.031 and 0.027 g histamine/100 g muscle and maximal bacteria concentrations of 1.75, 1.59 and 0.423 g dry cells/100 g muscle were observed in muscles of jack mackerel stored at 25, 15 and 5C, respectively. Incubated fish homogenates suggest rate and transport limitations in histamine formation in muscle. The Mulchandani model predicted bacterial growth in muscle. The Luedeking and Piret expression fitted histamine formation in muscle; , values were 3.0 × 10,3, 1.23 × 10,2 and 4.17 × 10,2 g histamine/g dry cells, while ,-values were 4.5 × 104, 8.0 × 10,5 and 0 g histamine/g dry cells × h at 25, 15, and 5C, respectively. The model predicts that jack mackerel could be stored from 4.5 to 5.5 days in ice, from 1 to 2 days at 15C and from 17 h to 2 days at 25C before fishmeal quality might be affected. [source] Histamine induces neural stem cell proliferation and neuronal differentiation by activation of distinct histamine receptorsJOURNAL OF NEUROCHEMISTRY, Issue 2 2008Anayansi Molina-Hernández Abstract Histamine has neurotransmitter/neuromodulator functions in the adult brain, but its role during CNS development has been elusive. We studied histamine effects on proliferation, cell death and differentiation of neuroepithelial stem cells from rat cerebral cortex in vitro. RT-PCR and Western blot experiments showed that proliferating and differentiated cells express histamine H1, H2 and H3 receptors. Treatments with histamine concentrations (100 nM,1 mM) caused significant increases in cell numbers without affecting Nestin expression. Cell proliferation was evaluated by BrdU incorporation; histamine caused a significant increase dependent on H2 receptor activation. Apoptotic cell death during proliferation was significantly decreased at all histamine concentrations, and cell death was promoted in a concentration-dependent manner by histamine in differentiated cells. Immunocytochemistry studies showed that histamine increased 3-fold the number of neurons after differentiation, mainly by activation of H1 receptor, and also significantly decreased the glial (astrocytic) cell proportion, when compared to control conditions. In summary, histamine increases cell number during proliferative conditions, and has a neuronal-differentiating action on neural stem cells, suggesting that the elevated histamine concentration reported during development might play a role in cerebrocortical neurogenesis, by activation of H2 receptors to promote proliferation of neural precursors, and favoring neuronal fate by H1 -mediated stimulation. [source] Skin reactivity to histamine and to allergens in unselected 9-year-old children living in Poland and ItalyPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 3 2003Roberto Ronchetti Several studies have shown a higher prevalence of positive skin-prick tests to airborne allergens in Western than in Eastern European countries. We have recently reported that skin histamine reactivity significantly increased in Italy over the past 15 years. Population differences in skin histamine reactivity could, at least in part, explain the reported differences in positive allergen skin tests. To test this hypothesis we compared histamine skin reactivity and the prevalence of allergen positive skin-prick tests in a sample of Italian and Polish schoolchildren. A total of 336 unselected 9-year-old-schoolchildren (198 in Italy and 138 in Poland) underwent skin-prick tests with three different histamine concentrations (10, 1 and 0.2 mg/ml) and with a panel of common airborne allergens according to the ISAAC protocol, phase two. Mean wheals elicited by skin-prick tests with the three serial concentrations of histamine were significantly larger (p < 0.001) and shifted more toward higher values (p < 0.001) in Italian than in Polish children. The differences were greater for the intermediate histamine concentration tested (1 mg/ml) than for the highest concentration (10 mg/ml). Skin-prick tests for airborne allergens were more frequently positive in Italian children: wheals ,,3 mm induced by any allergen [odds ratio (OR) 1.69; confidence interval (CI) 0.98,2.92] by Dermatophagoides pteronyssinus (OR 1.92; CI 0.97,3.80) and by D. farinae (OR 3.15; CI 1.16,8.63). Labeling as positive allergen wheal reactions half the size of the 10 mg/ml histamine wheal or larger reduced but did not abolish the Italian,Polish differences. The significantly higher skin histamine reactivity observed in Italian children could help to explain why allergen skin-test reactions differ in the East and West European populations. Moreover, differences in nonallergen-specific factors among populations should be considered in the interpretation of skin test results (e.g. cut-off points). To obtain meaningful results, epidemiological studies of allergies should include serial histamine dilutions. [source] ECL Cell Histamine Mobilization Studied byGastric Submucosal Microdialysis in Awake Rats:Methodological ConsiderationsBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2003Peter Ericsson They secrete histamine in response to circulating gastrin. Gastric submucosal microdialysis has been used to study ECL-cell histamine mobilization in awake rats. In the present study we assess the usefulness and limitations of the technique. Microdialysis probes were implanted in the gastric submucosa. Histological analysis of the stomach wall around the probe revealed a moderate, local inflammatory reaction 1,2 days after implantation; the inflammation persisted for at least 10 days. Experiments were conducted 3 days after the implantation. The "true" submucosal histamine concentration was determined by perfusing at different rates (the zero flow method) or with different concentrations of histamine at a constant rate (the no-net-flux method): in fasted rats it was calculated to be 87±5 (means±S.E.M.) nmol/l and 76±9 nmol/l, respectively. The corresponding histamine concentrations in fed rats were 93±5 and 102±8 nmol/l, respectively. With a perfusion rate of 74 ,l/hr the recovery of submucosal histamine was 49%, at 34 ,l/hr the recovery increased to 83%. At a perfusion rate below 20 ,l/hr the microdialysate histamine concentration was close to the actual concentration in the submucosa. The ECL-cell histamine mobilization was independent of the concentrations of Ca2+ in the perfusion medium (0,3.4 mmol/l Ca2+). In one experiment, histamine mobilization in response to gastrin (10 nmol/kg/hr subcutaneously) was monitored in rats pretreated with prednisolone (60 mg/kg) or indomethacin (15 mg/kg). The two antiinflammatory agents failed to affect the concentration of histamine in the microdialysate either before or during the gastrin challenge, which was in accord with the observation that the inflammatory reaction was modest and that inflammatory cells were relatively few around the probe and in the wall of the probe. In another experiment, rats were given aminoguanidine (10 mg/kg) or metoprine (10 mg/kg) 4 hr before the start of gastrin infusion (5 nmol/kg/hr intravenously). Metoprine (inhibitor of histamine N-methyl transferase) did not affect the microdialysate histamine concentration, while aminoguanidine (inhibitor of diamine oxidase) raised both basal and gastrin-stimulated histamine concentrations. We conclude that microdialysis can be used to monitor changes in the concentration of histamine in the submucosa of the stomach, and that the inflammatory reaction to the probe is moderate and does not affect the submucosal histamine mobilization. [source] | |||||||||||||