Cell Line | Condition | Specific l-Norepinephrine Uptake | |
---|---|---|---|
Km (nM) | Vmax (× 1018mol/cell/min) | ||
HEK-hNET | Vehicle | 587 ± 133 | 10.53 ± 0.88 |
β-PMA | 367 ± 168 | 6.14 ± 0.961-a | |
LLC-hNET | Vehicle | 680 ± 106 | 15.29 ± 2.32 |
β-PMA | 785 ± 128 | 11.31 ± 1.251-a | |
COS-7 (transient) | Vehicle | 880 ± 126 | 3.79 ± 1.11 |
β-PMA | 858 ± 118 | 2.35 ± 0.761-a |
Km and Vmax of l-NE transport was determined from saturation plots. Cells were incubated with either vehicle or β-PMA (1 μM) for 20 min before uptake assays with l-NE (10 min). Data are presented as means ± S.E.M. of three experiments performed in triplicate.
↵1-a Indicates P < .05 (Student’s unpaired ttest) as compared vehicle-treated cells. β-PMA induced decrease in Vmax of l-NE uptake as percent of vehicle-treated cells are presented in parentheses.