Autoradiographic distribution of [125I]-HPP-Senktide binding sites in the midbrain of SHR (A,B) and WKY (C,D). Total binding measured with 0.7 nM [125I]-HPP-Senktide is shown in panels A and C while the non-specific binding in the presence of 1 μM HPP-Senktide is shown in panels B and D. The areas under study are delimited by a white line. Abbreviations: SN, substantia nigra; VTA, ventral tegmental area; Hipp, hippocampus; A, amygdala.