| Abstract: | Cholecystokinin (CCK) and substance P (SP) concentrations were measured in discrete brain areas of adult male and diestrous female rats. Significant sex differences in CCK concentration were found in the ventromedial hypothalamic area, medial and lateral preoptic area, nucleus of the diagonal band of Broca, ventral tegmental area, entorhinal and in several cortical areas. No sex differences in SP concentrations were observed in any of these areas. However, significant sex differences in SP concentration were found in the amygdala. These data indicate that the CCK and to some extent the SP systems are sexually differentiated in certain brain areas. |
