‘Dark’ type Purkinje cells and neuronal ageing

Abstract

Eighty Wistar rats from age-groups of 3, 12 and 36 months were selected at random from the inbred colony. Ten animals from each group were treated with the ageingreversal drug, centrophenoxine (lOO mg/kg/day, intraperitoneally for 10 weeks). The Purkinje cell population of the brain of these animals were scanned histopathologically to record the impact of chronological age on the rate of conversion of 'light' into 'dark' type. The population of 'dark' cells increased by 52% from 3-36 months. The 'dark' neurons, even in the 3 month-old animals had substantial amount of histochemically detectable and autofluorescent age-pigment. While centrophenoxine could remove most of the pigment present in the 'light' type Purkinje neurons it failed to influence the pigment in any way in the 'dark' cells. The drug could not also influence the conversion of the 'light' cells into 'dark' type.

Simultaneous Demonstration of Microscopic Anatomy of Brainstem, Nissl Substance, Lipofuscin and Cytological Changes Using a Combination Method.

“…The fluorescence emitted by the pigment was similar to what was observed before pyronin staining or in the unstained preparations of the same tissue. This step also helped in demonstrating cytological changes associated with aging like chromatolysis and increased appearance of `dark' cells [15].…”

“…Some of the other prominent cytological changes in senile neurons are chromatolysis, pyroninophobe vacuolar spaces in both cytoplasm and nucleus, and loss of Nissl [13] as well as an increased population of `dark' cells [5,15].…”