Regional and lobular variation in neuronal lipofuscinosis in rat cerebellum: influence of age and protein malnourishment.

Abstract

Various factors other than ageing influence lipofuscinosis in neurons and other cells. Protein malnutrition is one such factor that has been studied. In the present study 3 months old rats were subjected to protein malnutrition (PM) for 3, 6 and 12 months by feeding them with low protein diet (4% protein). An age matched control group of rats was also maintained on a normal diet with high protein content (20% protein). The cerebella from the PM and control group rats were processed for histochemical, biochemical and fluorescent microscopic studies. Quantitative analysis of lipofuscin revealed that PM caused an increase in lipofuscin accumulation in the Purkinje neurons. A similar study on the Purkinje neurons of rats belonging to various age groups i.e. 6, 9 and 15 months, showed an increase in lipofuscin accumulation with age. Further, the increase in lipofuscinosis in ageing and PM rats was found to be varying. The maximum lipofuscin accumulation with PM was in the neurons of the 5th and 7th (75% and 71%, respectively) lobule of vermian region. The maximum increase in lipofuscin accumulation with age was found to be in lobule III (105.8%) of vermian region. Such a variation occurred in the hemisphere region also. Moreover, taking the two regions of cerebellum as a whole, neurons of the hemisphere region accumulated more amount of lipofuscin than those of the vermis region. The authors feel that the regional specificity of lipofuscin accumulation is to be studied in terms of the functional role of the various regions of a particular tissue in question.