The effects of genistein and erbstatin analogue, inhibitors of tyrosine kinase, on Ca2+ mobilization evoked by thapsigargin (TG) were examined in rat glioma C6 cells. Genistein and erbstatin analogue inhibited the Ca2+ release from intracellular pools as well as Ca2+ entry from extracellular medium evoked by TG in a dose-dependent manner. However, they did not affect a Ca2+ entry due to leakage of Ca2+ from extracellular medium into cells. The present results suggest that tyrosine kinase inhibitors inhibit capacitative Ca2+ entry due to the inhibition of both Ca2+ entry itself and Ca-2+ release in rat glioma C6 cells. (C) 1998 Elsevier Science Inc.