CYTOCHROME-OXIDASE ACTIVITY IN THE LATERAL GENICULATE-NUCLEUS OF POSTNATAL RATS

We have studied the cytochrome oxidase activity and its pattern of dis tribution in the dorsal lateral geniculate nucleus of the rat during p ostnatal development. Between the Ist and the 8th postnatal days, the geniculate nucleus is seen to have a homogeneous enzymatic pattern wit h high neuronal density and moderately reactive neuropil. On the 15th postnatal day, different levels of neuronal enzymatic activity are fou nd, and adult morphology is attained as of the 21st. The densitometric study has revealed that moderate and lightly reactive neurons are pre dominant between the Ist and the 8th postnatal days, whereas dark neur ons are more numerous and optical density maximum on the 15th postnata l day. No variation in the enzymatic pattern was observed between the 21st and the 42nd days.