Immobility from administration of the alpha1-adrenergic antagonist, terazosin, in the IVth ventricle in rats.
Brain alpha1-adrenoceptors have been shown to be essential for motor activity and movement in mice using intraventricular injection of alpha1-antagonists. To facilitate subsequent neuroanatomical mapping of these receptors, the present study was undertaken to replicate these effects in the rat. Rats were administered the alpha1-antagonist, terazosin, in the absence and presence of the alpha1-agonist, phenylephrine, in the IVth ventricle and were tested for their motor activity responses to an environmental change. Terazosin was found to produce a dose-dependent, virtually complete cessation of behavioral activity that was reversed by coinfusion of phenylephrine. The results could not be explained by sedation. It is concluded that central alpha1-adrenoceptors are essential for behavioral activation in rats as in mice.
Stone
Eric A
EA
Department of Psychiatry, Psychiatry MHL HN510, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA. es35@nyu.edu
Lin
Yan
Y
Quartermain
David
D
D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists / Q000008:administration & dosage*; D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004777:Environment; D007103:Immobilization; D007276:Injections, Intraventricular / Q000379:methods; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D010656:Phenylephrine / Q000494:pharmacology; D011224:Prazosin / Q000008:administration & dosage* / Q000031:analogs & derivatives*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D010656:Phenylephrine; C041226:Terazosin; D011224:Prazosin