Digitalis lactone and a triple-repeating sugar called a glycoside. Digitalis works by inhibiting sodium-potassium ATPase. This results in an increased intracellular concentration of sodium ions and thus a decreased concentration gradient across the cell membrane. This increase in intracellular sodium causes the Na/Ca exchanger to reverse potential, i.e., transition from pumping sodium into the cell in exchange for pumping calcium out of the cell, to pumping sodium out of the cell in exchange for pumping calcium into the cell. This leads to an increase in cytoplasmic calcium concentration, which improves cardiac contractility. Under normal physiological conditions, the cytoplasmic calcium used in
Radioactive contamination from the Rocky Flats Plant tests." As noted by Carl Johnson in Ambio, "Exposures of a large population in the Denver area to plutonium and other radionuclides in the exhaust plumes from the plant date back to 1953." Weapons production at the plant was halted after a combined FBI and EPA raid in 1989 and years of protests. The plant has since been shut down, with its buildings demolished and completely removed from the site. The Rocky Flats Plant was declared a Superfund site in 1989 and began its transformation to a cleanup site in February 1992. Removal of the plant and surface contamination was