PT - JOURNAL ARTICLE AU - EM Pich AU - M Lorang AU - M Yeganeh AU - F Rodriguez de Fonseca AU - J Raber AU - GF Koob AU - F Weiss TI - Increase of extracellular corticotropin-releasing factor-like immunoreactivity levels in the amygdala of awake rats during restraint stress and ethanol withdrawal as measured by microdialysis AID - 10.1523/JNEUROSCI.15-08-05439.1995 DP - 1995 Aug 01 TA - The Journal of Neuroscience PG - 5439--5447 VI - 15 IP - 8 4099 - http://www.jneurosci.org/content/15/8/5439.short 4100 - http://www.jneurosci.org/content/15/8/5439.full SO - J. Neurosci.1995 Aug 01; 15 AB - Previous research has suggested a role for corticotropin-releasing factor (CRF) in the anxiogenic effects of stressful stimuli and ethanol withdrawal. This hypothesis was explored in a series of experiments using intracranial microdialysis to monitor CRF-like immunoreactivity (CRF-IR) in the extracellular compartment of the rat amygdala. The synaptic origin of CRF-IR release in the amygdala was determined in vitro by assessing the Ca2+ dependency of 4-aminopyridine stimulated CRF-IR release from tissue preparations of rat amygdala. In vivo experiments were performed in awake rats after the placement of microdialysis probes in the amygdala. In the first experiment, transient restraint stress (20 min) produced an increase of CRF-IR release (basal levels, 1.19 +/- 0.15 fmol/50 microliters; stress levels, 4.54 +/- 1.33 fmol/50 microliters; p < 0.05) that returned to basal values within 1 hr. When 4-aminopyridine (5 mM) was added to the perfusion medium, it consistently increased CRF-IR release (4.83 +/- 0.92 fmol/50 microliters, p < 0.05). In the second experiment, CRF-IR release was measured during ethanol withdrawal in rats previously maintained for 2–3 weeks on a liquid diet containing ethanol (8.5%). Basal CRF-IR levels were 2.10 +/- 0.43 fmol/50 microliters in ethanol exposed rats and 1.30 +/- 0.19 fmol/50 microliters in control rats. During withdrawal, a progressive increase of CRF-IR levels over time was observed, reaching peak values at 10–12 hr after the onset of withdrawal (10.65 +/- 0.49 fmol/50 microliters vs 1.15 +/- 0.30 fmol/50 microliters of control rats, p < 0.01).