Mesolimbic dopamine and early post-6-OHDA lesion enhanced responses to d-amphetamine.
Bilateral lesions of mesolimbic dopamine (DA) reliably produce an attenuated response to amphetamine's locomotor stimulatory effects when administered after two weeks of surgical recovery. Several studies have revealed enhanced amphetamine-induced hyperactivity during the first postlesion week, however. In the present study, animals with bilateral 6-OHDA lesions of nucleus accumbens and olfactory tubercle DA showed an exaggerated response to 1.0 mg/kg amphetamine during this early period but were hypoactive in the absence of drug treatment. Neurochemical assay at 5 days revealed increased DA metabolism in the tubercle. Shifting patterns of postlesion amphetamine response under conditions of reduced mesolimbic DA are suggestive of dynamic adaptations in nondopaminergic systems.
Lynch
M R
MR
Research and Development Service, V.A. Medical Center, Syracuse, NY 13210.
Carey
R J
RJ
D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000818:Animals; D003913:Dextroamphetamine / Q000494:pharmacology*; D004298:Dopamine / Q000378:metabolism / Q000502:physiology*; D006719:Homovanillic Acid / Q000378:metabolism; D006892:Hydroxydopamines / Q000494:pharmacology*; D008032:Limbic System / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D016627:Oxidopamine; D051381:Rats; D011919:Rats, Inbred Strains
D006892:Hydroxydopamines; D015102:3,4-Dihydroxyphenylacetic Acid; D016627:Oxidopamine; D003913:Dextroamphetamine; D004298:Dopamine; D006719:Homovanillic Acid