BUY Thapsigargin

An intracellular Ca²⁺ immobilizer


Thapsigargin, derived from the plant genus Thapsia is an extremely tight-binding inhibitor of intracellular Ca²⁺�pumps. It was initially described as a tumor promoting agent which induces rapid Ca²⁺�release from intracellular stores by inhibition of the sarcoplasmic/endoplasmic reticulm Ca²⁺-dependent ATPase pump without inositol phosphate formation. The thapsigargin induced depletion of Ca²⁺�stores causes apoptosis in most cell lines. It has also been shown to cause histamine secretion from rat mast cells, and to stimulate arachidonic acid metabolism in macrophages. Its tumour-promoting function probably results, at least partly, from cytotoxicity, causing a wound response in skin. The tumorogenic activity of thapsigargin might be due to its activation of protein kinase B (Akt) which subsequently stimulates MAP kinase signaling via Src and Raf-1. Cell Signaling Activators and Inhibitors; Apoptosis Inducers, Cell Ca²⁺ Signaling > Intracellular Ca²⁺ Mobilizers