Effect of PKCβ inhibition on basal and AMPH-induced DAT trafficking in
WT mice. Striatal synaptosomes from WT mice were pretreated with either the
PKCβ-specific inhibitor LY (100 nM) or V for 1 h at 37°C. Surface DAT
expression was determined by biotinylation and quantified as described under
Materials and Methods. Data were expressed as percentage of DAT
surface expression (biotinylated DAT/lysate DAT) relative to control. A,
incubation with 100 nM LY for 1 h at 37°C significantly reduced basal
surface DAT expression compared with Veh treatment (LY versus V, paired
Student's t test, p < 0.05, n = 9). B, striatal
synaptosomes from WT mice were preincubated with 100 nM LY379196, then
challenged with 10 μM A or V for either 0.5 or 60 min. Short-term (0.5 min)
AMPH exposure resulted in a significant reduction in surface DAT expression
compared with Veh exposure (LY + V versus LY + 30-sec AMPH, paired Student's
t test, p < 0.05, n = 4), mimicking short-term
AMPH-induced DAT trafficking in KO mice. Conversely, long-term AMPH treatment
(60 min) increased surface DAT expression compared with Veh controls (LY + V
versus LY + 60-min AMPH, paired Student's t test, p <
0.01, n = 6), a similar pattern to KO mice. Data are represented as
mean ± S.E.M.