Abstract
It is known that catecholamine has an important role to regulate function of the brain. The sedation caused by reserpine, accompanying a decrease in the content of catecholamine in brain, is restored by administration of dopa (1-4). These results suggest that dopa is a precursor of catecholamine in brain and taken up into brain tissue from circulation system, through blood brain barrier and cell membrane, though catecholamine is considered to be difficult to permeate the blood brain barrier. Therefore, transport process of dopa into brain cell through cell membrane may have physiological meanings.
On the other hand, transport process at cell membrane is one of the most attractive biological problems. Active accumulation of amino acid in brain slices against concentration gradient has been known since a report of Stern (5), but the mechanism is remained in unclear. We examined transport of dopa into brain slices to get a clue to clarify mechanism of active transport of amino acid.
