Alzheimer's disease: distribution of changes in intraneuronal lipopigment in the frontal cortex

Brains from 22 patients with Alzheimer's disease (AD) and 20 non-diseased subjects were examined. Intraneuronal lipopigment in 2,440 nucleolated neurons throughout the depth of cortex was identified by fluorescence microscopy. In the AD brains, the mean total area per neuron of the outlines of lipopigment was significantly increased in the region adjacent to the brain surface (sixths 1-3), and analysis of variance showed a significant interaction between depth of cortex (in sixths) and AD for this lipopigment variable (p = 0.012). After relating this lipopigment variable to the size of neuronal bodies, the results indicate that this change occurs in pyramidal neurons, although other neuronal types may also be affected. At least one of three AD-related changes in lipopigment was found in each sixth of the depth of cortex.