Subcellular Distribution of Ascorbic Acid in Rat Brain.

Abstract
A low concentration of L-ascorbic acid (5 .times. 10-6 M) induced a Ca2+-dependent (10-6-10-5 M) acetylcholine [ACh] release from isolated synaptic vesicles in the presence of ATP and Mg2+. Ascorbic acid apparently may be associated with the function of the nervous system, particularly with dynamic states of transmitters in the nerve terminals. Under physiological conditions, concentration of ascorbic acid in the brain was over 2 mM, such levels being sufficient for ACh release. Accordingly the ACh release from the vesicles is considered to be physiologically regulated by Ca2+.