Summary
The influence of two α-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 μg/kg s.c. equieffectively inhibited exploratory activity. On the other hand only clonidine, which stimulates α2- and α2-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 α2-agonist B-HT 920 was ineffective under these conditions up to 30 mg/kg i.p. It is concluded, that in mice “sedative” α-adrenoceptors are of the α2- and “excitatory” of the α1-type.
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Pichler, L., Kobinger, W. Modulation of motor activity by α1 and α2 stimulation in mice. Naunyn-Schmiedeberg's Arch. Pharmacol. 317, 180–182 (1981). https://doi.org/10.1007/BF00500078
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DOI: https://doi.org/10.1007/BF00500078