Fig. 1.

Microinjection sites in the caudal subpostremal nucleus tractus solitarii (NTS) for all experiments. Schematic diagrams of transverse sections of the medulla oblongata from a rat brain. AP, area postrema; c, central canal; 10, dorsal motor nucleus of the vagus nerve; 12, nucleus of the hypoglossal nerve; Ts, tractus solitarius; Gr, gracile nucleus; Cu, cuneate nucleus. Scale is shown at the bottom; the no. on the left of the schematic diagram denotes the rostrocaudal position in mm of the section relative to the obex according to the atlas of the rat subpostremal NTS by Barraco et al. (1). Microinjection sites were marked with fluorescent dye and are denoted with the following symbols: A, microinjections of N⁶-cyclopentyladenosine (CPA) in intact animals (filled circles), after bilateral adrenalectomy (open triangles), and following β-adrenergic blockade (open circles); B, microinjections of CPA after V₁ vasopressin receptor blockade (open square), following bilateral sinoaortic denervation (open circle with dot), after combined adrenalectomy and V₁ vasopressin receptor blockade (filled square) and following combined sinoaortic denervation and adrenalectomy (plus symbol).