Structural dimorphism in the mammillary bodies of the rat.

Diverse structures of the CNS show sexual differences in the anatomical and functional organization. In particular, many dimorphic nuclei have been found in the hypothalamus: the preoptic area, suprachiasmatic nucleus and ventromedial hypothalamus. Our investigation has shown a statistically significant difference in relation to volume of the medial mammillary and left lateral nuclei, and the number of glial cells of the medial mammillary nucleus. The volume and glial cell population is greater in the male than in the female. Thus, the existence of dimorphic functions in which this structure could be involved are discussed herein.