ER-Tracker Green dye is cell-permeant, live-cell stain that is highly selective for the endoplasmic reticulum (ER) that when stained using the protocol provided, the staining pattern is partially retained after fixation with formaldehyde. This stain consists of the green-fluorescent BODIPY FL dye and glibenclamide. Glibenclamide (glyburide) binds to the sulphonylurea receptors of ATP-sensitive K+ channels which are prominent on ER; the pharmacological activity of glibenclamide could potentially affect ER function. Variable expression of sulphonylurea receptors in some specialized cell types may result in non-ER labeling.