Amygdala regulation of nucleus accumbens dopamine output is governed by the prefrontal cortex.
A dynamic interaction between the prefrontal cortex (PFC), amygdala, and nucleus accumbens (NAc) may be fundamental to regulation of goal-directed behavior by affective and cognitive processes. This study demonstrates that a mechanism for this triadic relationship is an inhibitory control by prefrontal cortex on accumbal dopamine release during amygdala activation. In freely moving rats, microstimulation of basolateral amygdala at intensities that produced mild behavioral activation produced an expected rapid increase in glutamate efflux in the prefrontal cortex and the nucleus accumbens shell region of the ventral striatum. However, during the stimulation, dopamine release increased only in the prefrontal cortex, not in the nucleus accumbens. An increase in accumbal dopamine release was observed during the stimulation if glutamate activation in the prefrontal cortex was inhibited at either presynaptic or postsynaptic levels. Some behaviors expressed during the stimulation were intensified in animals in which prefrontal cortex glutamate activation was blocked. In addition, these animals continued to express stimulus-induced behaviors after the termination of stimulation, whereas normal poststimulus behaviors such as ambulation and grooming were not displayed as frequently. Considering that dopamine neurotransmission in the nucleus accumbens is thought to play an integral role in goal-directed motor behavior, these findings suggest that the prefrontal cortex influences the behavioral impact of amygdala activation via a concomitant active suppression of accumbal dopamine release. Absence of this cortical influence appears to result in an aberrant pattern of behavioral expression in response to amygdala activation, including behavioral perseveration after stimulus termination.
Jackson
M E
ME
Department of Psychiatry, Yale University School of Medicine, West Haven, Connecticut 06516, USA.
Moghaddam
B
B
D000679:Amygdala / Q000502:physiology*; D000818:Animals; D001070:Appetitive Behavior / Q000187:drug effects / Q000502:physiology; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D001643:Bridged Bicyclo Compounds / Q000008:administration & dosage; D004298:Dopamine / Q000378:metabolism*; D004558:Electric Stimulation; D004567:Electrodes, Implanted; D018690:Excitatory Amino Acid Agonists / Q000008:administration & dosage; D018698:Glutamic Acid / Q000378:metabolism; D007546:Isoquinolines / Q000008:administration & dosage; D008297:Male; D017551:Microdialysis; D008845:Microinjections; D009714:Nucleus Accumbens / Q000378:metabolism*; D017397:Prefrontal Cortex / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors; D013239:Stereotyped Behavior / Q000187:drug effects / Q000502:physiology; D013777:Tetrazoles / Q000008:administration & dosage; D014851:Wakefulness
D001643:Bridged Bicyclo Compounds; D018690:Excitatory Amino Acid Agonists; D007546:Isoquinolines; D018091:Receptors, AMPA; D013777:Tetrazoles; D018698:Glutamic Acid; C082309:tezampanel; C104753:eglumetad; D004298:Dopamine