Free and total lipid myo-inositol concentrations decrease with age in human brain.

An active transport system maintains myo-inositol in the brain at a much higher concentration than in the blood. Free and total lipid inositol has been analysed in samples of normal human anterior temporal cortex of different ages. At age 20 the concentration of inositol was 60 mumols/g protein, and it fell steadily to half that concentration at age 90. There was a similar fall with age in the total inositol lipid concentration.