Z. Kristofikova et al., EFFECTS OF K-DEPOLARIZATION, ARACHIDONIC-ACID, ETHANOL, AND AGING ON THE HIGH-AFFINITY CHOLINE TRANSPORT IN RAT HIPPOCAMPUS(), Neurochemical research, 23(7), 1998, pp. 923-929
The Na+-dependent high-affinity choline uptake (HACU) transport and th
e [H-3]hemicholinium-3 ([H-3]HC-3) specific binding were measured on h
ippocampal synaptosomes of young (3-6 months) and old (22 months) Wist
ar rats. In vitro effects of 100-300 mu M arachidonic acid (PLA) and o
f 5% ethanol were tested under basal as well as stimulated (55 mM KCl)
conditions. The influence of AA (an irreversible decrease of HACU and
a reversible increase of [H-3]HC-3 binding) was more marked under sti
mulated rather than basal conditions in brain tissue of young rats. Th
e increased K+-depolarization effect on HACU and the decreased influen
ce of AA on [H-3]HC-3 binding were estimated in brain tissue of old co
mpared to young rats. Results suggest the involvement of different poo
ls of the high-affinity choline carrier and marked changes due to agin
g in the regulation of the HACU transport.