Metabolism of eicosanoids and their action on renal function during ischaemia and reperfusion: the effect of alprostadil.
Eicosanoids, active metabolites of arachidonic acid (AA), play an important role in the regulation of renal haemodynamics and glomerular filtration. Our study verified the hypothesis on the positive action of exogenously administered PGE(1) on renal function during an operation with temporary ischaemia of the lower half of the body. Also the effect of alprostadil (prostaglandin E(1) analogue) administered during the operation of an abdominal aorta aneurysm on the postoperative systemic metabolism of AA and the glomerular filtration rate (GFR) was investigated. The study included 42 patients with a diagnosed abdominal aorta aneurysm who have been qualified for the operation of implantation of the aortic prosthesis. The patients were randomly assigned to two groups: the study group (I) receiving alprostadil and the control group (II) without alprostadil. The levels of hydroxyeicosatetraenoic acids (15-HETE, 12-HETE, 5-HETE) were determined by RP-HPLC and the level of thromboxane B(2) (TxB(2)) was determined by ELISA in the plasma of the blood drawn from vena cava superior immediately before aortic clamping (A) and 5 min after aortic declamping (B). The administration of PGE(1) affects the metabolism of 15-HETE in a manner dependent on the baseline value of GFR but does not significantly change the postoperative renal function. The metabolism of 15-HETE is affected by the baseline value of GFR1 and a longer period of ischaemia is correlated with lower concentrations of 5-HETE during reperfusion. The results of our studies indicate that TxB(2) influences the postoperative function of kidneys.