Anticonvulsant effects of clonidine mediated through central alpha2-adrenoceptors.
The effects of centrally (0.3-30 ng/kg) and peripherally (0.01 microgram/kg-1.0 mg/kg) administered clonidine on PTZ-induced seizures was studied in rats. At low doses, dose-dependent decreases in the duration of seizures was observed but at higher doses the duration returned to control levels. Anticonvulsant activity was antagonized by yohimbine (100 microgram/kg i.p.) indicating alpha2-adrenoceptor involvement, whereas the second phase of the response was antagonized by prazosin (10 ng/kg i.c.v.) indicating that it involved alpha1-adrenoceptors.
D000818:Animals; D000927:Anticonvulsants; D001921:Brain / Q000187:drug effects; D003000:Clonidine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D007276:Injections, Intraventricular; D008297:Male; D011224:Prazosin / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011941:Receptors, Adrenergic / Q000502:physiology*; D011942:Receptors, Adrenergic, alpha / Q000502:physiology*; D015016:Yohimbine / Q000494:pharmacology
D000927:Anticonvulsants; D011941:Receptors, Adrenergic; D011942:Receptors, Adrenergic, alpha; D015016:Yohimbine; D003000:Clonidine; D011224:Prazosin