The authors study mechanisms of nephrotoxic action of high osmolar rad
iopaque substance (RPS) and the role of endothelin-1, hormonal endothe
lial factor, in these mechanisms in patients with different variants o
f chronic glomerulonephritis. Endothelin-1 is a potent endogenic vasoc
onstrictor participating in regulation of intrarenal hemodynamics and
renal function the synthesis of which is related to Ca metabolism. Mec
hanisms of nephrotoxic action of RPS involve disturbances of Ca metabo
lism (hypercalciemia), high concentration of blood endothelin-1 which
directly correlated with baseline creatinine in the serum and deterior
ation of renal function after RPS introduction. Ca ions antagonists (c
orinfar) contribute to prevention of changes in endothelin-1 synthesis
and relevant renal dysfunction induced by RPS.