Regional CNS Levels of Acetylcholine and Choline During Hypoglycemic Stupor and Recovery

Abstract
During insulin stupor in mice, acetylcholine levels in cerebral cortex, cerebellum, brainstem, striatum and hippocampus were unchanged from control values despite brain glucose concentrations 3-10% of normal. Choline levels rose 2.4- to 3.6-fold in all 5 CNS regions. Brain acetylcholine and choline levels did not change during recovery following glucose injection. In hypoglycemic stupor, the overall rates of acetylcholine synthesis and degradation apparently remain balanced within each of the CNS regions; the biochemical mechanism that elevates brain choline levels is probably not related only to cholinergic synaptic processes; and brain choline levels need not rise for stupor to occur.