We compared the effects of dextrans with a molecular weight of 35 kDa oxidized by chemical (OD(ch)) and radiochemical (OD(r)) methods on oxidative and metabolic functions of peritoneal macrophages from BALB/c mice in vitro and in vivo. It was found that none type of dextrans exhibits chemiluminescent properties. In vitro study showed that OD(ch) had a priming effect on mouse peritoneal macrophages, while OD(r) did not potentiate the oxidative and metabolic response of cells to zymosan. Being injected intraperitoneally, OD(r) more markedly enhanced chemiluminescent response of mouse peritoneal macrophages and reduced their viability than OD(ch). Thus, both dextrans are biocompatible, but in OD(ch) this parameter is higher.