AMPA-receptor involvement in c-fos expression in the medial prefrontal cortex and amygdala dissociates neural substrates of conditioned activity and conditioned reward

• Published in: The European journal of neuroscience 1999-11, Vol.11 (11), p.4089-4098
• Main Authors: Mead, Andy N., Vasilaki, Anna, Spyraki, Christina, Duka, Theodora, Stephens, David N.
• Format: Article
• Language: English
• Subjects: amphetamine; Amphetamines; Amygdala - physiology; Animals; Brain; Caustic soda; Choice Behavior - drug effects; Choice Behavior - physiology; conditioned place preference; Conditioning, Operant - physiology; Dextroamphetamine - pharmacology; Drugs; Gene Expression Regulation; Male; Mice; Mice, Inbred C57BL; Mice, Inbred Strains; Motor Activity - drug effects; Motor Activity - physiology; mouse; Neurons - physiology; nucleus accumbens; Nucleus Accumbens - physiology; Prefrontal Cortex - physiology; Proto-Oncogene Proteins c-fos - analysis; Proto-Oncogene Proteins c-fos - genetics; Quinoxalines - pharmacology; Receptors, AMPA - antagonists & inhibitors; Receptors, AMPA - physiology; Reward; sensitization
• ISSN: 0953-816X; 1460-9568
• DOI: 10.1046/j.1460-9568.1999.00828.x

Exposure to an environment, previously conditioned to amphetamine (1 mg/kg, i.p.), induced locomotor activity and c‐fos expression (a marker for neuronal activation) in the mouse medial prefrontal cortex (mPFC) and amygdala; acute or repeated amphetamine (1 mg/kg, i.p.) administration induced c‐fos expression additionally in the nucleus accumbens. An α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole propionate (AMPA)‐receptor antagonist, 2,3‐dihydroxy‐6‐nitro‐7‐sulphamoyl‐benzo(f)quinoxaline (NBQX), blocked expression of conditioned activity, and prevented the increase in c‐fos expression in mPFC, implicating mPFC AMPAergic transmission in the conditioned component of behavioural sensitization to amphetamine. NBQX failed to block the expression of amphetamine‐conditioned place preference, a measure of conditioned reward, or conditioned c‐fos expression in the amygdala, an area implicated in the expression of conditioned place preference. These findings indicate that the conditioned components of behavioural sensitization depend on AMPA‐receptor‐mediated activation in mPFC, but that conditioned reward does not.