Fig. 1.

Dose-related Fos-ir induction in response to central CRF. Bright-field photomicrographs are of immunoperoxidase preparations to show Fos-ir expression in the piriform cortex (PIR) and adjoining regions of saline-treated controls, and rats given icv injections of 1 or 10 μg CRF 2 hr before they were killed. Relative to low levels of expression seen in vehicle-treated animals, 1 μg CRF provokes Fos-ir in piriform cortex, the endopiriform nucleus (EPd), and the nucleus of the lateral olfactory tract (NLOT); substantially more robust responses of similar topography are seen in rats receiving 10 μg doses of peptide. Amyg, Amygdala. All photomicrographs 30× magnification.