[MORPHOLOGICAL BASES OF REORGANIZATION OF THE RAT CEREBELLAR CORTEX IN SENESCENCE]

A histological and immunohistochemical study of the cerebellar cortex of senescent Wistar rats (36-month-old) was performed in comparison to young rats (36-month-old).The cerebellar cortex of senescent animals typically showed degeneration of the Purkinje cells accompanied by immunochemically determined loss of the calcium-binding protein calbindin. These results suggest that presence of calbindin in the Purkinje cells is a criterion of functional activity of these neurons. The Purkinje cells degeneration is accompanied by lesion of the synaptophysin-containing basket cell networks, which is an indication of impaired function of inhibitory (GABAergic) axo-axonal synapses. During senescence significant rear-rangement is observed in the glomeruli of the granular layer of the cerebellum, which are the structures where primary afferent animals disintegrate suggesting of alteration in the transmission of information from the cerebrum to the cerebellum.