ESCAPABLE AND INESCAPABLE STRESS DIFFERENTIALLY ALTER EXTRACELLULAR LEVELS OF 5-HT IN THE BASOLATERAL AMYGDALA OF THE RAT

The effects of escapable and yoked inescapable electric tailshocks on extracellular levels of serotonin (5-HT) in the basolateral amygdala w ere measured by in vivo microdialysis. Inescapable, but not escapable, shock increased extracellular 5-HT in the amygdala relative to restra ined controls. Basal levels of 5-HT were elevated 24 h after inescapab le shock, and previously inescapably shocked subjects exhibited an exa ggerated 5-HT response to two brief footshocks. Levels of extracellula r 5-HIAA did not follow any particular pattern and were not correlated with the changes in 5-HT. (C) 1998 Elsevier Science B.V. All rights r eserved.