Neurochemical evidence for denervation supersensitivity: the effect of unilateral substantia nigra lesions on apomorphine-induced increases in neostriatal acetylcholine levels |
| |
Authors: | H C Fibiger D S Grewaal |
| |
Institution: | Division of Neurological Sciences Department of Psychiatry The University of British Columbia Vancouver, Canada |
| |
Abstract: | Unilateral lesions of the nigro-neostriatal dopaminergic projection were induced by injections of 6-hydroxydopamine into the zona compacta of the substantia nigra. This resulted in a reduction of neostriatal dopamine to less than 6 percent of the control side. Two months later intraperitoneal injections of apomorphine (1 mg/kg) produced contralateral turning and a significant increase in neostriatal acetylcholine levels. The increase was significantly greater in the neostriatum ipsilateral to the lesion than in the intact side. Haloperidol (1 mg/kg) produced a significant decrease in neostriatal acetylcholine but this decrease did not differ between the “denervated” and intact neostriata. The nigral 6-hydroxydopamine lesions did not by themselves affect neostriatal acetylcholine levels. The fact that apomorphine produces a greater increase in neostriatal acetylcholine after lesions of the dopaminergic nigro-neostriatal projection supports earlier behavioral data suggestive of denervation supersensitivity of neostriatal dopaminergic receptors after these lesions. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |