Reduced Phosphoinositide Concentrations in Anterior Temporal Cortex of Alzheimer‐Diseased Brains

: Samples of brain anterior temporal cortex from 17 patients with Alzheimer's disease and 18 age‐matched controls have been analysed for myo‐inositol and the three phosphoinositides. There was significantly less phosphati‐dylinositol in the Alzheimer samples (1.36 μmol/g wet weight) than in the controls (2.28 μmol/g). The concentrations of phosphatidylinositol 4‐phosphate and phosphati‐dylinositol 4,5‐bisphosphate were also lower in Alzheimer cortex, but differences from the control group were not statistically significant. Free myo‐inositol concentrations were 5.11 μmol/g (Alzheimer) and 4.44 μmol/g (control) and again the difference was not significant. The lack of phosphoinositides in Alzheimer temporal cortex may impair receptor function.