myo-inositol: a newly identified nonnitrogenous osmoregulatory molecule in mammalian brain

Pediatr Res. 1989 Nov;26(5):482-5. doi: 10.1203/00006450-198911000-00024.


Sugar alcohols have been found to play an important osmoregulatory role both in unicellular organisms and, more recently, in multicellular organisms, including mammals. This study shows that myo-inositol accumulates in the brains of chronically hypernatremic mice, as had been earlier found in rats, and demonstrates for the first time a profound decrease of myo-inositol in the brains of chronically hyponatremic mice. Together with decreases in better known cerebral osmoles (amino acids and related nitrogenous compounds), the decrease in myo-inositol apparently allows the brain to balance its intracellular osmolality with that of the plasma, permitting a normal brain water content (no edema) despite profound hyponatremia.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adaptation, Physiological
  • Animals
  • Brain / metabolism*
  • Hypernatremia / metabolism
  • Hyponatremia / metabolism
  • Inositol / metabolism*
  • Mice
  • Water-Electrolyte Balance


  • Inositol