Increase in Exogenous Choline Fails to Elevate the Content or Turnover Rate of Cortical, Striatal, or Hippocampal Acetylcholine

Abstract

The present experiments were designed to test whether increasing the availability of choline to rat brain increases the rate of acetylcholine synthesis in that organ. The content of choline and acetylcholine and the turnover rate of acetylcholine in striatum, hippocampus, and cerebral cortex were measured following changes in dietary choline, intraperitoneal choline, or intravenous infusion of choline. Increasing plasma choline caused some increase in tissue choline but did not increase acetylcholine levels nor acetylcholine turn-over rate in any of the areas of brain studied. Indeed, in hippocampus, choline decreased the turnover rate of acetylcholine.