Growth inhibition of cultured smooth muscle cells by corrosion products of316 L stainless steel wire

The potential cytotoxicity on vascular smooth muscle cells of corrosion pro ducts from 316 L stainless steel, one of most popular biomaterials, of intr avascular stents, has not been highlighted. In this investigation, 316 L st ainless steel wires were corroded in Dulbecco's modified eagle's medium wit h applied constant electrochemical breakdown voltage, and the supernatant a nd precipitates of corrosion products were prepared as culture media. The e ffects of different concentrations of corrosion products on the growth of r at aortic smooth muscle cells were conducted with the [H-3]thymidine uptake test and cell cycle sorter. Both the supernatant and precipitates of corro sion products were toxic to the primary culture of smooth muscle cells. The growth inhibition was correlated well with the increased nickel ions in th e corrosion products when nickel concentration was above 11.7 ppm. The corr osion products also changed cell morphology and induced cell necrosis. The cell growth inhibition occurred at the G0/G1 to S transition phase. Similar to our recent study of nitinol stent wire, the present investigation also demonstrated the cytotoxicity of corrosion products of 316 L stainless stee l stent wire on smooth muscle cells, which might affect the poststenting va scular response. (C) 2001 John Wiley & Sons, Inc.