Histochemical patterns of succinic semialdehyde dehydrogenase activity within the Purkinje cell population during rat cerebellar histogenesis.

The histochemical detection of SSADH activity corroborates some crucial steps of the maturation of Purkinje neurons in rat cerebellum. The SSADH-specific activity seems to appear early, within the first week of postnatal life, in a few Purkinje cells. Around the 12th day most cells were SSADH positive, even if some were still negative. This period is an important step of postnatal histogenesis when many histological and physiological data show important neuronal changes. At the end of cerebellar histogenesis the SSADH activity showed the same pattern as in adult rats. Our findings suggest that in the Purkinje cell population the maturation does not occur simultaneously thus confirming the concept of "heterogeneity" (different functional states).