Identification of an excitatory amino acid-mediated component of the ventral tegmental area local field potential response to medial prefrontal cortex stimulation: effect of acute d-amphetamine.
The induction of sensitisation to the behavioural effects of d-amphetamine - a model of drug addiction - involves the potentiation of exctiatory amino acid (EAA)-ergic synapses on dopaminergic neurons in the ventral tegmental area (VTA). Such potentiation has been reported as early as 2 hr post-injection, however earlier time points have not been assessed. Consequently, we examined the effects of systemic d-amphetamine on an EAA-mediated component of the VTA local field potential response to stimulation of the medial prefrontal cortex, an EAAergic afferent critical for sensitisation, over the immediate 2 hr post-injection period. D-amphetamine and saline both depressed the amplitude of this component to a similar extent throughout the recording session. It is concluded that overt aspects of EAA-mediated potentiation appear to be delayed with respect to drug administration, which may have implications for sensitisation's putative role in linking drug-related environmental stimuli and the central effects of the drug.
Dommett
E J
EJ
Department of Psychology, University of Sheffield, Western Bank, Sheffield, UK.
Simpson
J
J
Clark
D
D
Overton
P G
PG
D000818:Animals; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D003913:Dextroamphetamine / Q000494:pharmacology*; D004558:Electric Stimulation; D018846:Excitatory Amino Acids / Q000378:metabolism*; D008297:Male; D008839:Microelectrodes; D009473:Neuronal Plasticity / Q000502:physiology; D017397:Prefrontal Cortex / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D019966:Substance-Related Disorders / Q000503:physiopathology*; D017557:Ventral Tegmental Area / Q000187:drug effects* / Q000378:metabolism
D000697:Central Nervous System Stimulants; D018846:Excitatory Amino Acids; D003913:Dextroamphetamine