title: Role of the amygdala in the coordination of behavioral, neuroendocrine, and prefrontal cortical monoamine responses to psychological stress in the rat.
abstract: Exposure to mild stress is known to activate dopamine (DA), serotonin (5-HT), and norepinephrine (NE) metabolism in the anteromedial prefrontal cortex (m-PFC). Neuroanatomical site(s) providing afferent control of the stress activation of the m-PFC monoaminergic systems is at present unknown. The present study used a conditioned stress model in which rats were trained to fear a substartle-threshold tone paired previously with footshock and assessed for behavioral, neuroendocrine, and neurochemical stress responses. Bilateral NMDA-induced excitotoxic lesioning of the basolateral and central nuclei of the amygdala was performed before or after training. Pretraining amygdala lesions blocked stress-induced freezing behavior, ultrasonic vocalizations, adrenocortical activation, and dopaminergic metabolic activation in the m-PFC. Post-training amygdala lesions blocked stress-induced m-PFC DA, 5-HT, and NE metabolic activation. Post-training amygdala lesions also blocked stress-induced freezing and defecation, and greatly attenuated adrenocortical activation. These data provide evidence of amygdalar control of stress-induced metabolic activation of the monoaminergic systems in the m-PFC, as well as amygdalar integration of behavioral and neuroendocrine components of the rat stress response. These results are discussed in terms of possible relevance to stress-induced exacerbation of schizophrenic symptoms and the pathophysiology of posttraumatic stress disorder.
authors.affiliation: Interdepartmental Program in the Neurosciences, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
authors.forename: L E
authors.initials: LE
authors.lastname: Goldstein
authors.forename: A M
authors.initials: AM
authors.lastname: Rasmusson
authors.forename: B S
authors.initials: BS
authors.lastname: Bunney
authors.forename: R H
authors.initials: RH
authors.lastname: Roth
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000679:Amygdala / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D015306:Biogenic Monoamines / Q000378:metabolism*; D003345:Corticosterone / Q000378:metabolism; D008297:Male; D017397:Prefrontal Cortex / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013315:Stress, Psychological / Q000378:metabolism / Q000503:physiopathology*
chemical_list: D015306:Biogenic Monoamines; D015102:3,4-Dihydroxyphenylacetic Acid; D003345:Corticosterone