Abstract |
Potential species differences in cardiovascular responses to histamine H3 receptor activation were studied in the conscious guinea pig, rabbit, normotensive rat and the spontaneously hypertensive rat. R- alpha-Methylhistamine (100 micrograms/kg i.v.) decreased blood pressure in both the guinea pig and the rabbit. In the guinea pig, R- alpha-methylhistamine decreased heart rate, whereas in the rabbit it produced a tachycardia. In the normotensive rat and spontaneously hypertensive rat, R- alpha-methylhistamine (100 micrograms/kg i.v.) had no effect on blood pressure and heart rate. The cardiovascular action of R- alpha-methylhistamine in the guinea pig and rabbit was blocked by pretreatment with thioperamide (1.0 mg/kg i.v.) but not by chlorpheniramine (0.3 mg/kg i.v.) or cimetidine (3.0 mg/kg i.v.), respectively. These results indicate species differences in cardiovascular responses to histamine H3 receptor activation.
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Authors | R L McLeod, S B Gertner, J A Hey |
Journal | European journal of pharmacology
(Eur J Pharmacol)
Vol. 259
Issue 2
Pg. 211-4
(Jul 01 1994)
ISSN: 0014-2999 [Print] Netherlands |
PMID | 7957615
(Publication Type: Comparative Study, Journal Article)
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Chemical References |
- Histamine Agonists
- Histamine Antagonists
- Methylhistamines
- Piperidines
- Receptors, Histamine H3
- alpha-methylhistamine
- Cimetidine
- thioperamide
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Topics |
- Animals
- Blood Pressure
(drug effects)
- Cimetidine
(pharmacology)
- Guinea Pigs
- Heart Rate
(drug effects)
- Hemodynamics
(drug effects)
- Histamine Agonists
(pharmacology)
- Histamine Antagonists
- Male
- Methylhistamines
(pharmacology)
- Piperidines
(pharmacology)
- Rabbits
- Rats
- Rats, Inbred SHR
- Rats, Sprague-Dawley
- Receptors, Histamine H3
(metabolism)
- Species Specificity
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