Carbon Dioxide → Desipramine

Participants

Reaction Steps

On day 1, cells were plated at 3,000 cells/well in growth medium and maintained in a cell incubator (37° C., 5% CO2). On day 2, growth medium was replaced with 200 μl of assay buffer (25 mM HEPES; 120 mM NaCl; 5 mM KCl; 2.5 mM CaCl2; 1.2 mM MgSO4; 2 mg/ml glucose (pH 7.4, 37° C.)) containing 0.2 mg/ml ascorbic acid and 10 μM pargyline. Plates containing cells with 200 μl of assay buffer were equilibrated for 10 minutes at 37° C. prior to addition of compounds. A stock solution of desipramine was prepared in DMSO (10 mM) and delivered to triplicate wells containing cells for a final test concentration of 1 μM. Data from these wells were used to define non-specific NE uptake (minimum NE uptake). Test compounds were prepared in DMSO (10 mM) and diluted in assay buffer according to test range (1 to 10,000 nM). Twenty-five microliters of assay buffer (maximum NE uptake) or test compound were added directly to triplicate wells containing cells in 200 μl of assay buffer. The cells in assay buffer with test compounds were incubated for 20 minutes at 37° C. To initiate the NE uptake, [3H]NE diluted in assay buffer (120 nM final assay concentration) was delivered in 25 μl aliquots to each well and the plates were incubated for 5 minutes (37° C.). The reaction was terminated by decanting the supernatant from the plate. The plates containing cells were washed twice with 200 μl assay buffer (37° C.) to remove free radioligand. The plates were then inverted, left to dry for 2 minutes, then reinverted and air-dried for an additional 10 minutes. The cells were lysed in 25 μl of 0.25 N NaOH solution (4° C.), placed on a shake table and vigorously shaken for 5 minutes. After cell lysis, 75 μl of scintillation cocktail was added to each well and the plates were sealed with film tape. The plates were returned to the shake table and vigorously shaken for a minimum of 10 minutes to ensure adequate partitioning of organic and aqueous solutions. The plates were counted in a Wallac Microbeta counter (PerkinElmer) to collect the raw cpm data.

Provenance & Evidence