Fig. 2.

Distribution of mCPP-induced FOS-IR in the NTS. (A–F) 0.9% saline or (G-L) 5.0 mg/kg mCPP were administered i.v. at the onset of the dark cycle and 2 h later, rats were euthanized, brains extracted, prepared, and processed for FOS-IR. Displayed are representative photomicrographs of the nucleus of the solitary tract (NTS). Distances from bregma are (A and G) −11.28 mm, (B and H) −12.24 mm, (C and I) −12.60 mm, (D and J) −13.56 mm, (E and K) −14.04 mm and (F and L) −15.00 mm. mCPP selectively induced FOS-IR in a discrete region of the NTS (distance from bregma −13.56 mm to −14.40 mm) corresponding to the level of the area postrema (AP). Scale bar panel L, 1 mm, applies to (A)–(L).