Glomerular Prostaglandin and Thromboxane Synthesis in Rat Nephrotoxic Serum Nephritis EFFECTS ON RENAL HEMODYNAMICS

ation by isolated rat glomeruli was assessed in vitro in antiglomerular basement membrane (anti-GBM) an-tibody-induced glomerulonephritis by radioimmu-noassay for prostaglandins (PG) and thromboxane. After a single intravenous injection of rabbit anti-rat GBM serum, we observed enhancement of glomerular thromboxane B2 (TxB2) synthesis as early as 2 to 3 h with smaller increments in PGF2a, PGE2 and 6-keto-PGFIa synthetic rates. On day 2 of the disease, the glomerular synthesis of TxB2 and, to a lesser extent, PGF20 and PGE2 remained enhanced, whereas on days 8, 11, and 14, TxB2 was the only prostanoid synthesized at increased rates. Glomerular TxB2 synthesis corre-lated with the presacrifice 24-h protein excretion. 60 min after intravenous infusion of anti-GMB serum, glomerular filtration rate (GFR) decreased (0.66±0.04 to 0.44±0.03 ml/min per 100 g, P < 0.05), without a significant change in renal plasma flow (RPF): 1.97±0.23 to 1.80±0.23 ml/min per 100 g) and without a change in glomerular PG synthetic rates. At 2 h, GFR and RPF reached a nadir (0.25±0.04 and 1.3±0.1 ml/ min per 100 g, respectively) coinciding with a fivefold increment in glomerular TxB2. By 3 h GFR and RPF partially recovered to 0.43±0.07 and 1.77±0.20 ml