Effects of the nootropic AWD 52-39 on the blood-brain transfer of leucine, choline and glucose in rats after 14-d exposure to ethanol

Abstract

The transport of the neutral amino acid L-leucine as well as of choline and D-glucose across the blood-brain barrier (BBB) of male Wistar rats was studied after 14-day exposure to ethanol and treatment with the nootropic drug AWD 52-39 (1). After ethanol exposure the half-saturation constant (Km) and the maximum velocity of transport (Vmax) declined in the majority of the investigated brain regions. Also, the treatment elicited a regionally different increase of the permeability-surface area (PS) product of choline (between 10% and 33%) and glucose (between 12% and 27%). The changes in the blood-brain transfer of the three compounds were diminished or prevented by additional application of 1. The cerebral blood flow was increased by the exposure to ethanol by maximally 44%. After additional administration of 1 the changes were reversed and the blood flow reached control values. In addition, the activity of the enzyme acetylcholine esterase was determined in the striatum and the hippocampus. After ethanol exposure the enzyme activity declined by 32%. It was less diminished after treatment with 1. The latter effects let assume that the changes of the BBB permeability elicited by ethanol and 1 are related to alterations of brain metabolism.