Difference in the age-related accumulation of lipopigments in the adrenergic and nonadrenergic peripheral neurons in the male rat.

The age-related accumulation of lipopigments was determined in the adrenergic and nonadrenergic peripheral neurons of the rat using a microspectrofluorometric method and electron microscopy, 3-, 12- and 30-month-old rats were used. The rate of lipopigment accumulation was greater in nonadrenergic than adrenergic neurons. The nonadrenergic neurons showed an emission maximum at 500 nm, while the emission maximum of adrenergic neurons was at 515-520 nm. Electron microscopy revealed a neuromelanin-like component in the pigment bodies of adrenergic neurons but not in nonadrenergic neurons. The results indicate that age-related lipopigment accumulation has a differential and selective pattern also in the peripheral nervous system.