Role of intracellular signalling pathways in hydrogen peroxide-induced injury to rat glomerular mesangial cells.

1. Brief exposure of cultured rat glomerular mesangial cells (GMC) to H2O2 in nominally bicarbonate-free solution induced a rapid dose dependent, dantrolene-inhibitable increase in intracellular free Ca2+ from 65 +/- 6 to 203 +/- 14 nmol/L and a prolonged release of [14C]-arachidonic acid [14C]-AA which preceded the onset of cell membrane damage assessed by trypan-blue uptake. 2.

Inhibition of rat glomerular mesangial cell sodium/hydrogen exchange by hydrogen peroxide.

1. pHi regulation in glomerular mesangial cells (GMC) includes both Na+/H+ and Cl-/HCO3-exchange. As a fall in pHi may protect against H2O2-mediated GMC damage during ischaemia-reperfusion, the involvement of these mechanisms in the GMC pH1 response to H2O2 was assessed using confluent GMC grown in RPMI medium with 20% fetal calf serum (10-15 passages).