Modulation of motor activity by alpha 1- and alpha 2-adrenoceptor stimulation in mice.
The influence of two alpha-adrenoceptor agonists, clonidine and B-HT 920, on motor activity was tested in mice. Both, clonidine and B-HT 920 (2-amino-6-allyl-5,6,7,8-tetrahydro-4H-thiazolo-[4,5-d]-azepine) in the dose range 30--300 micrograms/kg s.c. effectively inhibited exploratory activity. On the other hand only clonidine, which stimulates alpha 2- and alpha 1-adrenoceptors increased locomotor activity in mice treated with reserpine (5 mg/kg) and apomorphine (3 mg/kg) in the doses of 0.3 and 1 mg/kg i.p. The highly selective alpha 2-agonist B-HT 920 was ineffective under these conditions up to 30 mg/kg i.p. It is concluded, that in mice "sedative" alpha-adrenoceptors are of the alpha 2- and "excitatory" of the alpha 1-type.
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001381:Azepines / Q000494:pharmacology; D003000:Clonidine / Q000494:pharmacology; D005106:Exploratory Behavior / Q000187:drug effects; D008297:Male; D051379:Mice; D009043:Motor Activity / Q000187:drug effects*; D013844:Thiazoles / Q000494:pharmacology
D000316:Adrenergic alpha-Agonists; D001381:Azepines; D013844:Thiazoles; C024763:talipexole; D003000:Clonidine; D001058:Apomorphine