In vitro extracellular recording from nigral dopamine neurons following continuous d-amphetamine infusion.
Single nigral dopamine neurons were extracellularly recorded in vitro after withdrawal from continuous d-amphetamine sulfate infusion (5.0 mg/kg per day for 7 days via subcutaneous osmotic minipumps). Seven days after withdrawal, the dopamine neurons were supersensitive to impulse-inhibition by dopamine. This increased sensitivity suggests a supersensitivity of soma/dendritic autoreceptors on these neurons, as we previously hypothesized based on a supersensitivity to intravenous apomorphine. In contrast to the day 7, the withdrawal day 1 was associated with a normosensitivity to dopamine, suggesting that the apomorphine subsensitivity observed in vivo on this day may be secondary to non-autoreceptor changes.
Lee
T H
TH
Department of Psychiatry, Duke University Medical Center, Durham, NC 27710.
Ellinwood
E H
EH
Zhang
H
H
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D003913:Dextroamphetamine / Q000008:administration & dosage / Q000494:pharmacology*; D004298:Dopamine / Q000502:physiology*; D015918:Infusion Pumps, Implantable; D008297:Male; D009474:Neurons / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013375:Substance Withdrawal Syndrome / Q000503:physiopathology*; D013378:Substantia Nigra / Q000166:cytology / Q000187:drug effects*
D003913:Dextroamphetamine; D004298:Dopamine