Strontium ion (Sr²⁺)

Strontium ion (Sr²⁺) is the divalent cation form of the alkaline earth metal strontium, chemically similar to calcium and able to replace it in various biological processes[7][9]. In medicine, strontium ions are not themselves traditional therapeutic targets like receptors or enzymes but are used as pharmacologically active agents. Strontium-89 chloride, a radioactive isotope, is injected to relieve bone pain from metastases by localizing in actively remodeling bone and emitting therapeutic beta radiation[2]. Strontium ranelate, an oral drug, releases Sr²⁺ to promote osteoblast function and inhibit osteoclast differentiation, used for osteoporosis treatment[6][4], but carries significant cardiovascular risks. Both natural and synthetic strontium ions are studied in tissue engineering for bone regeneration, exploiting their osteogenic and angiogenic properties[8]. While Sr²⁺ is not a biological "target" per se, its effects arise from chemical mimicry of Ca²⁺ in mineralized tissues and signaling pathways. Clarification: Strontium ion (Sr²⁺) is not a receptor, transport protein, enzyme, or typical drug target, but an inorganic ion. Therefore, this entry is likely *incorrect or inappropriate* for traditional drug target databases or lists, though it remains pharmacologically relevant in therapeutic contexts as a component of drugs and biomaterials[7][6][8][2].

Other names

Strontium(2+) ionSR2+Sr²⁺

Strontium ranelate: Dual action—stimulates osteoblasts, inhibits osteoclast differentiation through OPG/RANKL pathway, and enhances bone formation markers. Strontium-89 chloride: Mimics calcium, localizes to bone and delivers beta-radiation for tumoricidal and analgesic effects.