[Phosphoinositide metabolism in sections of the cortex of the large hemisphere of the brain in anoxia].

Depolarization (an increased concentration of KCL in the medium) has been investigated for its effect on the content and turnover rate of phospholipid phosphorus from the rat brain cortex slice under normal oxygen supply and under anoxia. It is shown that anoxia results in a small increase of phosphatidyl-inositol-4.5-bisphosphate (PIP2) and phosphatidylinositol-4-phosphate (PIP) content and in the depression of the turnover rate of all the phosphoinositides. Depolarization leads to a decrease in PIP2 concentration with a simultaneous increase in their turnover rate, these results being more expressed under anoxia. The development of depolarization by the 5th min. of anoxia in vivo leads, most probably, to the enhanced PIP2 breakdown, that is to a progressive decrease in their content.