Tasisulam (LY573636) is an apoptosis inducer and an antitumor agent via the intrinsic pathway.

Electrophysiology: The human IKCa1 is cloned and expressed in COS-7 cells. Cells are studied in the whole-cell configuration of the patch-clamp technique. The holding potential is 280 mV. The internal pipette solution contains: 145 mM K+ aspartate, 2 mM MgCl2, 10 mM Hepes, 10 mM K2EGTA, and 8.5 mM CaCl2 (1 μM free Ca2+), pH 7.2, 290-310 mOsm. To reduce currents from the native chloride channels in COS-7 cells, Na+ aspartate Ringer is used as an external solution: 160 mM Na+ aspartatey/4.5 mM KCl/2 mM CaCl2/1 mM MgCl2/5 mM Hepes, pH 7.4/290-310 mOsm. IKCa currents in COS-7 cells are elicited by 200-ms voltage ramps from -120 mV to 40 mV applied every 10 seconds and the reduction of slope conductance at -80 mV by TRAM-34 taken as a measure of channel block.

Cells are treated with various concentrations of LY573636. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay is performed. Briefly, MTT is dissolved in phosphate-buffered saline (PBS) at 5 mg/mL. Approximately 1,000 cells per well are incubated in culture medium for 96 hours in 96-well plates; and then, 10 μL of the MTT solution is added. After a 4-hour incubation, 100 μL of solubilization solution (20 % sodium dodecyl sulfate [SDS]) is added, and the mixture was incubated at 37 °C for 16 hours. In this assay, MTT is cleaved to an orange formazan dye by metabolically active cells; and the absorbance of the formazan product is measured with an enzyme-linked immunoabsorbent assay (ELISA) reader at 540 nm. (Only for Reference)

他司磺胺, LY573636

Ethanol: 77 mg/mL (185.49 mM), Sonication is recommended.

DMSO: 77 mg/mL (185.49 mM), Sonication is recommended.

H2O: < 1 mg/mL (insoluble or slightly soluble)

10% DMSO+40% PEG300+5% Tween 80+45% Saline: 2 mg/mL (4.82 mM), Sonication is recommended.