Serotonin Modulation of Sensory Inputs to the Lateral Amygdala: Dependency on Corticosterone

摘要: The lateral nucleus of the amygdala (LA) receives excitatory (glutamatergic) inputs from thalamic and cortical sensory processing areas is believed to be involved in evaluation affective significance events. We examined whether serotonin (5-HT) affects transmission auditory afferents LA and, if so, this modulation regulated by stress hormone corticosterone (CORT). Neuronal activity was elicited via iontophoretic ejection L-glutamate or synaptically electrical stimulation afferent pathways. In intact rat, iontophoretically applied 5-HT inhibited both glutamate-evoked action potentials most neurons examined. However, after adrenalectomy (ADX), which eliminates endogenous CORT, no longer evoked LA. High-CORT doses given ADX animals reinstated inhibition 5-HT, whereas low-CORT had little effect. Immunocytochemical labeling glucocorticoid receptor rat demonstrated nuclear staining throughout several regions, including ADX, visible. With a high replacement dose CORT (5 10 mg) dense returned, but with low (1 mg/kg), there only light staining. Thus, ability modulate glutamatergic pathways dependent on presence possibly activation. Via mechanism, modulates information within thus may regulate amygdala-related functions.