the barbiturates ( amytal , pentothal ) , whilst having no significant effects on labelled acetylcholine synthesis in unstimulated brain except at high concentration ( 1mm ) , diminished or abolished ( at 0.25 or 0.5mm ) the enhanced release of acetylcholine , due to high k ( + ) or lack of ca ( 2+ ) .
C0006104
brain
C0086045
concentration