2-Thiazolylethylamine, a selective histamine H1 agonist, decreases seizure susceptibility in mice.
The effects of intracerebroventricular (ICV) administration of histamine and its selective agonists on electrically and pentylenetetrazole-induced convulsions in mice were studied. The ICV administration of histamine decreased seizure susceptibility on electrically and pentylenetetrazole-induced convulsions significantly and dose-dependently. The inhibitory effects of histamine were well antagonized by centrally acting histamine H1 antagonists such as pyrilamine (or mepyramine) and ketotifen, but not by a peripherally acting histamine H1 antagonist, astemizole, or a centrally acting H2 antagonist, zolantidine. The ICV administration of 2-thiazolylethylamine, a selective histamine H1 agonist, also decreased seizure susceptibility, which could be antagonized by centrally acting histamine H1 antagonists, whereas dimaprit, a selective histamine H2 agonist, did not affect seizure susceptibility. These findings strengthened the idea that the central histaminergic neuron system plays an inhibitory role in convulsions.
Yokoyama
H
H
Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan.
Onodera
K
K
Iinuma
K
K
Watanabe
T
T
D000818:Animals; D000927:Anticonvulsants / Q000008:administration & dosage / Q000494:pharmacology*; D017259:Dimaprit / Q000008:administration & dosage / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004597:Electroshock; D006632:Histamine / Q000008:administration & dosage / Q000494:pharmacology; D017442:Histamine Agonists / Q000008:administration & dosage / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D006634:Histamine H1 Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D006635:Histamine H2 Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D007276:Injections, Intraventricular; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010433:Pentylenetetrazole; D011969:Receptors, Histamine H1 / Q000187:drug effects*; D012640:Seizures / Q000139:chemically induced / Q000517:prevention & control*; D013844:Thiazoles / Q000008:administration & dosage / Q000037:antagonists & inhibitors / Q000494:pharmacology*
D000927:Anticonvulsants; D017442:Histamine Agonists; D006634:Histamine H1 Antagonists; D006635:Histamine H2 Antagonists; D011969:Receptors, Histamine H1; D013844:Thiazoles; C029345:2-(2-aminoethyl)thiazole; D006632:Histamine; D010433:Pentylenetetrazole; D017259:Dimaprit