PMID- 11514069
OWN - NLM
STAT- MEDLINE
DCOM- 20011204
LR  - 20190701
IS  - 0304-3940 (Print)
IS  - 0304-3940 (Linking)
VI  - 309
IP  - 3
DP  - 2001 Aug 31
TI  - Substantial loss of substrate by diffusion during uptake in HEK-293 cells 
      expressing neurotransmitter transporters.
PG  - 173-6
AB  - Human embryonic kidney 293 (HEK-293) cells stably transfected with the human 
      serotonin (5-HT) or dopamine transporter (hSERT, hDAT), or the rat GABA 
      transporter GAT-1 were incubated with saturating concentrations of transporter 
      substrates (hSERT: [(3)H]5-HT, [(3)H]N-methyl-phenyl-pyridinium (MPP+); hDAT: 
      [(3)H]dopamine, [(3)H]MPP(+); rGAT: [(3)H]GABA). Uptake velocities decreased 
      significantly over time for [(3)H]5-HT and [(3)H]dopamine (already visible at 1 
      min), but not for [(3)H]MPP(+) or [(3)H]GABA. In efflux experiments cells were 
      preloaded and substrate diffusion into the medium was studied following the 
      addition of appropriate uptake inhibitors. Fractional effluxes were (% min(-1)) 
      1.27, 0.72, 0.27 and 0.08 for [(3)H]5-HT, [(3)H]dopamine, [(3)H]MPP(+) and 
      [(3)H]GABA, respectively. The results suggest that in uptake experiments the more 
      lipophilic substrates [(3)H]5-HT and [(3)H]dopamine leave the cells by diffusion 
      already after a short time (1 min) of accumulation.
FAU - Scholze, P
AU  - Scholze P
AD  - Pharmacological Institute, University of Vienna, Waehringer Strasse 13a, 1090 
      Vienna, Austria. petra.scholze@univie.ac.at
FAU - Sitte, H H
AU  - Sitte HH
FAU - Singer, E A
AU  - Singer EA
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Ireland
TA  - Neurosci Lett
JT  - Neuroscience letters
JID - 7600130
RN  - 0 (Carrier Proteins)
RN  - 0 (Dopamine Plasma Membrane Transport Proteins)
RN  - 0 (GABA Plasma Membrane Transport Proteins)
RN  - 0 (Membrane Glycoproteins)
RN  - 0 (Membrane Proteins)
RN  - 0 (Membrane Transport Proteins)
RN  - 0 (Nerve Tissue Proteins)
RN  - 0 (Neurotransmitter Uptake Inhibitors)
RN  - 0 (Organic Anion Transporters)
RN  - 0 (SLC6A1 protein, human)
RN  - 0 (SLC6A4 protein, human)
RN  - 0 (Serotonin Plasma Membrane Transport Proteins)
RN  - 0 (Slc6a1 protein, rat)
RN  - 0 (Slc6a4 protein, rat)
RN  - 333DO1RDJY (Serotonin)
RN  - 56-12-2 (gamma-Aminobutyric Acid)
RN  - R865A5OY8J (1-Methyl-4-phenylpyridinium)
RN  - VTD58H1Z2X (Dopamine)
SB  - IM
MH  - 1-Methyl-4-phenylpyridinium/metabolism
MH  - Animals
MH  - Carrier Proteins/*biosynthesis
MH  - Cell Line/*metabolism
MH  - Diffusion
MH  - Dopamine/metabolism
MH  - Dopamine Plasma Membrane Transport Proteins
MH  - GABA Plasma Membrane Transport Proteins
MH  - Humans
MH  - Kidney
MH  - Membrane Glycoproteins/*biosynthesis
MH  - Membrane Proteins/*biosynthesis
MH  - Membrane Transport Proteins/*biosynthesis
MH  - *Nerve Tissue Proteins
MH  - Neurotransmitter Uptake Inhibitors/*metabolism
MH  - *Organic Anion Transporters
MH  - Rats
MH  - Serotonin/metabolism
MH  - Serotonin Plasma Membrane Transport Proteins
MH  - gamma-Aminobutyric Acid/metabolism
EDAT- 2001/08/22 10:00
MHDA- 2002/01/05 10:01
CRDT- 2001/08/22 10:00
PHST- 2001/08/22 10:00 [pubmed]
PHST- 2002/01/05 10:01 [medline]
PHST- 2001/08/22 10:00 [entrez]
AID - S0304394001020584 [pii]
AID - 10.1016/s0304-3940(01)02058-4 [doi]
PST - ppublish
SO  - Neurosci Lett. 2001 Aug 31;309(3):173-6. doi: 10.1016/s0304-3940(01)02058-4.