Involvement of alpha-adrenoceptors in para-hydroxyamphetamine-induced head-twitch response.
The effect of some drugs with a higher selectivity for either the alpha 1- or alpha 2-adrenoceptors on the head-twitches induced by intracerebroventricular administration of p-hydroxyamphetamine (p-OHA) in mice, have been studied. Pretreatment with yohimbine increased the number of head-twitches induced by p-OHA, whereas pretreatment with clonidine or prazosin reduced the number of responses. The decrease in head-twitches produced by clonidine was completely antagonized by pretreatment with yohimbine. Pretreatment with 6-hydroxydopamine prior to the combined treatment with clonidine and p-OHA, resulted in recovery of the reduced level head-twitches to the level induced by p-OHA alone. Pretreatment with 6-hydroxydopamine alone resulted in a marked increase in the number of p-OHA-induced head-twitches. These results clearly indicate that a noradrenaline system in the brain may, at least in part, be involved in the p-OHA-induced head-twitches in mouse, most probably by modulating a serotonergic system which is responsible for the head-twitch response.
Tadano
T
T
Department of Pharmacology, Tohoku College of Pharmacy, Sendai, Japan.
Satoh
S
S
Kisara
K
K
Arai
Y
Y
Kinemuchi
H
H
D000662:Amphetamines / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000502:physiology*; D010136:p-Hydroxyamphetamine / Q000494:pharmacology*
D000662:Amphetamines; D011942:Receptors, Adrenergic, alpha; D010136:p-Hydroxyamphetamine