Amygdala β-noradrenergic receptors modulate delayed downregulation of dopamine activity following restraint.
Stress, which involves a heightened arousal and excitability, triggers important adaptive responses to maintain homeostasis and prepare a response. In the current studies, we administered a psychological stressor of 2 h acute restraint on rats, and found that 24 h after the cessation of the restraint session, there was a significant decrease in ventral tegmental area dopaminergic (DA) neuron population activity and a significant attenuation in amphetamine-induced locomotor activity. Systemic or intra-basolateral nuclei of the amygdala administration of the β-noradrenergic receptor antagonist, propranolol, reversed the decrease, suggesting that the delayed attenuation of DA neuron firing following a stressor depends on a noradrenaline-mediated mechanism. This alteration in DA activity may adaptively prepare the individual to avoid the stressor, or in the extreme, may be a factor that contributes to pathological changes in behavior or physiological responses.
Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA. changch@pitt.edu
Chun-hui
CH
Chang
Anthony A
AA
Grace
D059331:Adrenergic Neurons / Q000378:metabolism*; D000679:Amygdala / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D004298:Dopamine / Q000378:metabolism*; D015536:Down-Regulation; D004594:Electrophysiology; D007150:Immunohistochemistry; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012149:Restraint, Physical; D013315:Stress, Psychological / Q000378:metabolism*
D004298:Dopamine