[Sexual dimorphism in human medial raphe nuclei. Preliminary study with the Golgi cox method]

Brains from a female and a male newborn who died from an asphictic syndrome were examined to study the cytoarchitecture of the median raphe nucleus using the Golgi-Cox and morphometric methods. This nucleus is part of the serotonergic system. The morphometric analysis showed in the female newborn a significant increase of neurons. Also she had a higher proportion of ovoid and multipolar cells and a lower proportion of fusiform cells than the newborn male. Our findings suggest that this neuronal distribution may be the anatomical substrate for a serotonergic specific system in each sex.