The Experts below are selected from a list of 36 Experts worldwide ranked by ideXlab platform
Manfred Göthert - One of the best experts on this subject based on the ideXlab platform.
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Involvement of presynaptic H_3 receptors in the inhibitory effect of histamine on serotonin release in the rat brain cortex
Naunyn-Schmiedeberg's Archives of Pharmacology, 1990Co-Authors: Klaus Fink, Eberhard Schlicker, A. Neise, Manfred GöthertAbstract:Rat brain cortex slices or synaptosomes preincubated with ^3H-serotonin were superfused with physiological salt solution (which, in the case of slices, contained citalopram, an inhibitor of serotonin uptake), and the effects of histamine and related drugs on the evoked tritium overflow were studied. The electrically (3 Hz) evoked tritium overflow from slices was inhibited by histamine and the H_3 receptor agonists R-(−)-α-methylhistamine and Nα-methylhistamine (pIC_12.5 values: 6.41, 7.28 and 6.12, respectively), but not affected by the H_1 receptor agonist 2-(2-thiazolyl)ethylamine and the H_2 receptor agonist dimaprit (each at 10 μmol/l). The concentration-response curve for histamine was shifted to the right by the H_3 receptor antagonists impromidine, Burimamide and thioperamide (apparent pA_2 values: 7.45, 5.97 and 7.88, respectively); the concentration-response curve of serotonin for its inhibitory effect on the electrically evoked overflow was not affected by the three drugs (apparent pA_2 values: < 5.5, < 5.5 and < 6.5). Given alone, impromidine, thioperamide and a low concentration of Burimamide facilitated the electrically evoked overflow. In slices superfused with K^+-rich, Ca^2+-free solution containing tetrodotoxin throughout and in synaptosomes superfused with Ca^2+-free solution, histamine inhibited the overflow evoked by introduction of Ca^2+ (in synaptosomes, simultaneously with an increased amount of K^+). In either tissue, the effect of histamine was counteracted by thioperamide. The results provide evidence that exogenous and probably also endogenous histamine inhibits serotonin release in the rat brain cortex via presynaptic histamine H_3 receptors.
Klaus Fink - One of the best experts on this subject based on the ideXlab platform.
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Involvement of presynaptic H_3 receptors in the inhibitory effect of histamine on serotonin release in the rat brain cortex
Naunyn-Schmiedeberg's Archives of Pharmacology, 1990Co-Authors: Klaus Fink, Eberhard Schlicker, A. Neise, Manfred GöthertAbstract:Rat brain cortex slices or synaptosomes preincubated with ^3H-serotonin were superfused with physiological salt solution (which, in the case of slices, contained citalopram, an inhibitor of serotonin uptake), and the effects of histamine and related drugs on the evoked tritium overflow were studied. The electrically (3 Hz) evoked tritium overflow from slices was inhibited by histamine and the H_3 receptor agonists R-(−)-α-methylhistamine and Nα-methylhistamine (pIC_12.5 values: 6.41, 7.28 and 6.12, respectively), but not affected by the H_1 receptor agonist 2-(2-thiazolyl)ethylamine and the H_2 receptor agonist dimaprit (each at 10 μmol/l). The concentration-response curve for histamine was shifted to the right by the H_3 receptor antagonists impromidine, Burimamide and thioperamide (apparent pA_2 values: 7.45, 5.97 and 7.88, respectively); the concentration-response curve of serotonin for its inhibitory effect on the electrically evoked overflow was not affected by the three drugs (apparent pA_2 values: < 5.5, < 5.5 and < 6.5). Given alone, impromidine, thioperamide and a low concentration of Burimamide facilitated the electrically evoked overflow. In slices superfused with K^+-rich, Ca^2+-free solution containing tetrodotoxin throughout and in synaptosomes superfused with Ca^2+-free solution, histamine inhibited the overflow evoked by introduction of Ca^2+ (in synaptosomes, simultaneously with an increased amount of K^+). In either tissue, the effect of histamine was counteracted by thioperamide. The results provide evidence that exogenous and probably also endogenous histamine inhibits serotonin release in the rat brain cortex via presynaptic histamine H_3 receptors.
A. Neise - One of the best experts on this subject based on the ideXlab platform.
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Involvement of presynaptic H_3 receptors in the inhibitory effect of histamine on serotonin release in the rat brain cortex
Naunyn-Schmiedeberg's Archives of Pharmacology, 1990Co-Authors: Klaus Fink, Eberhard Schlicker, A. Neise, Manfred GöthertAbstract:Rat brain cortex slices or synaptosomes preincubated with ^3H-serotonin were superfused with physiological salt solution (which, in the case of slices, contained citalopram, an inhibitor of serotonin uptake), and the effects of histamine and related drugs on the evoked tritium overflow were studied. The electrically (3 Hz) evoked tritium overflow from slices was inhibited by histamine and the H_3 receptor agonists R-(−)-α-methylhistamine and Nα-methylhistamine (pIC_12.5 values: 6.41, 7.28 and 6.12, respectively), but not affected by the H_1 receptor agonist 2-(2-thiazolyl)ethylamine and the H_2 receptor agonist dimaprit (each at 10 μmol/l). The concentration-response curve for histamine was shifted to the right by the H_3 receptor antagonists impromidine, Burimamide and thioperamide (apparent pA_2 values: 7.45, 5.97 and 7.88, respectively); the concentration-response curve of serotonin for its inhibitory effect on the electrically evoked overflow was not affected by the three drugs (apparent pA_2 values: < 5.5, < 5.5 and < 6.5). Given alone, impromidine, thioperamide and a low concentration of Burimamide facilitated the electrically evoked overflow. In slices superfused with K^+-rich, Ca^2+-free solution containing tetrodotoxin throughout and in synaptosomes superfused with Ca^2+-free solution, histamine inhibited the overflow evoked by introduction of Ca^2+ (in synaptosomes, simultaneously with an increased amount of K^+). In either tissue, the effect of histamine was counteracted by thioperamide. The results provide evidence that exogenous and probably also endogenous histamine inhibits serotonin release in the rat brain cortex via presynaptic histamine H_3 receptors.
Eberhard Schlicker - One of the best experts on this subject based on the ideXlab platform.
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Involvement of presynaptic H_3 receptors in the inhibitory effect of histamine on serotonin release in the rat brain cortex
Naunyn-Schmiedeberg's Archives of Pharmacology, 1990Co-Authors: Klaus Fink, Eberhard Schlicker, A. Neise, Manfred GöthertAbstract:Rat brain cortex slices or synaptosomes preincubated with ^3H-serotonin were superfused with physiological salt solution (which, in the case of slices, contained citalopram, an inhibitor of serotonin uptake), and the effects of histamine and related drugs on the evoked tritium overflow were studied. The electrically (3 Hz) evoked tritium overflow from slices was inhibited by histamine and the H_3 receptor agonists R-(−)-α-methylhistamine and Nα-methylhistamine (pIC_12.5 values: 6.41, 7.28 and 6.12, respectively), but not affected by the H_1 receptor agonist 2-(2-thiazolyl)ethylamine and the H_2 receptor agonist dimaprit (each at 10 μmol/l). The concentration-response curve for histamine was shifted to the right by the H_3 receptor antagonists impromidine, Burimamide and thioperamide (apparent pA_2 values: 7.45, 5.97 and 7.88, respectively); the concentration-response curve of serotonin for its inhibitory effect on the electrically evoked overflow was not affected by the three drugs (apparent pA_2 values: < 5.5, < 5.5 and < 6.5). Given alone, impromidine, thioperamide and a low concentration of Burimamide facilitated the electrically evoked overflow. In slices superfused with K^+-rich, Ca^2+-free solution containing tetrodotoxin throughout and in synaptosomes superfused with Ca^2+-free solution, histamine inhibited the overflow evoked by introduction of Ca^2+ (in synaptosomes, simultaneously with an increased amount of K^+). In either tissue, the effect of histamine was counteracted by thioperamide. The results provide evidence that exogenous and probably also endogenous histamine inhibits serotonin release in the rat brain cortex via presynaptic histamine H_3 receptors.
Hendrik Timmerman - One of the best experts on this subject based on the ideXlab platform.
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new analogs of Burimamide as potent and selective histamine h3 receptor antagonists the effect of chain length variation of the alkyl spacer and modifications of the n thiourea substituent
Journal of Medicinal Chemistry, 1995Co-Authors: R C Vollinga, W M P B Menge, Rob Leurs, Hendrik TimmermanAbstract:Burimamide was one of the first compounds reported to antagonize the activation of the histamine H 3 receptor by histamine. We have prepared a large series of Burimamide analogs by variation of the alkyl spacer length of Burimamide from two methylene groups to six methylene groups and also by replacement of the N-methyl group with other alkyl and aryl groups. All analogs are reversible, competitive H 3 antagonists as determined on the guinea pig intestine. Elongation of the alkyl chain from an ethylene chain to a hexylene chain results in an increase of the H 3 antagonistic activity. The H 3 selective pentylene and hexylene analogs of Burimamide are about 10 times more potent than Burimamide. The N-thiourea substituents, however, have no beneficial influence on the affinity.