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Methamphetamine and amphetamine influence biophysical properties of dopamine transporter in a phosphorylation – dependent manner
Author(s) -
Davari Paran,
Villarroel Laura,
Saha Kaustuv,
Cartier Etienne,
Khoshbouei Habibeh
Publication year - 2013
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.27.1_supplement.885.3
Subject(s) - meth , dopamine transporter , methamphetamine , chemistry , dopamine , amphetamine , fluorescence recovery after photobleaching , phosphorylation , transporter , biophysics , pharmacology , biochemistry , endocrinology , biology , membrane , monomer , organic chemistry , acrylate , gene , polymer
The psychostimulants amphetamine (AMPH) & methamphetamine (METH) increase synaptic dopamine (DA) by competing with DA uptake and stimulating the reverse transport of DA via dopamine transporter (DAT). At maximally effective concentrations, METH releases twice as much [Ca 2+ ] in from internal stores as AMPH. [Ca 2+ ] in responses to both drugs were inhibited by DAT antagonists. We have shown that the intact N‐terminal phosphorylation sites on DAT molecule is required for the enhanced effects of METH on [Ca 2+ ] in mobilization. We used discontinuous sucrose gradient centrifugation and Fluorescence Recovery After Photobleaching (FRAP) to examine the microdomain distribution, diffusion rate (D) and mobile fraction (Mf) of Yellow Fluorescent Protein (YFP)‐tagged DAT (YFP‐DAT), in Chinese Hamster Ovarian cells and mice neurons before and after METH exposure. METH exposure (10μM/10min) increases DAT levels in the raft fraction & slows the lateral mobility of YFP‐DAT at the surface membrane. METH exposure significantly decreased the D and Mf of YFP‐DAT as compared to vehicle control (p < 0.05, n= 15–23 cells). Our ongoing studies examine the hypothesis that METH‐regulation of DAT mobility is due to METH‐induced increase in [Ca 2+ ] in and is dependent on Nphosphorylation of DAT. Funding was provided by DA026947/DA/NIDA and NS071122/NS/NINDS