THE DIFFERENCE IN AUTOFLUORESCENCE FEATURES OF LIPOFUSCIN BETWEEN BRAIN AND ADRENAL

Lipofuscin is the autofluorescent material, which accumulates with agi ng in the cells of various tissues. However, its autofluorescence char acteristics are different among tissues. In the present study, the aut ofluorescence features of lipofuscin in the brain and adrenal were com pared. In 18-21-month-old rats, the brain lipofuscin was granular and its autofluorescence was bright whitish-yellow to bright orange. On th e contrary, the adrenal lipofuscin was not demarkated as granules, and its autofluorescence was subdued orange. The emission maximum of the bright whitish-yellow brain lipofuscin was 540 nm to 570 nm and that o f the adrenal lipofuscin was 640 nm to 660 nm, when excited at 330 nm to 380 nm. When the spectra were drawn after correcting the wavelength -dependent bias of microspectrofluorometer, the autofluorescence spect ra were consistent with microscopically observable tint. To conclude, the present results showed that the autofluorescence features of the b right whitish-yellow brain lipofuscin and the adrenal lipofuscin were quite different.