Magnesium lithospermate B improves renal function via the kallikrein-prostaglandin system in rats with renal failure.

The effect of magnesium lithospermate B on the renal responses of rats with renal failure was investigated in the presence and absence of pretreatment with the kallikrein inhibitor, aprotinin. Magnesium lithospermate B caused a marked increase in the levels of the renal functional parameters (glomerular filtration rate, renal plasma flow and renal blood flow), accompanied by significant increases in urinary prostaglandin excretion (increases of prostaglandin E2 and 6-keto-prostaglandin F1 alpha excretion by 82% and 36%, respectively). The urinary excretion of kallikrein was also increased following magnesium lithospermate B administration. However, pretreatment with aprotinin abolished the renal function-facilitating action of magnesium lithospermate B concomitantly with a markedly increased urinary excretion of prostaglandin E2, 6-keto-prostaglandin F1 alpha and kallikrein. These results suggest that the kallikrein-kinin-prostaglandin B.