Extracellular ATP promotes cellular growth of glomerular mesangial cells mediated via phospholipase C

The present study was undertaken to determine whether extracellular ATP promotes cellular growth of glomerular mesangial cells. ATP increased inositol 1,4,5-trisphosphate (IP3) production and cellular free calcium concentration ([Ca2+]i) in a dose-dependent manner. None of ADP, AMP or adenosine caused an increase in IP3 production or [Ca2+]i mobilization. Also, ATP activated mitogen-activated protein (MAP) kinase and 3H-thymidine incorporation and increased the absorbance by colorimetric assay in a dose-dependent manner. Again, either of ADP, AMP or adenosine had no effect. These results indicate that extracellular ATP binds to P2 purinergic receptors and activates phospholipase C in glomerular mesangial cells. Such a signal transduction promotes cellular growth of mesangium.