We investigated whether indomethacin, a prostaglandin (PG) synthesis inhibitor, modulates the effect of norepinephrine on the autoregulation of the renal blood flow(RBF) in anesthetized dogs. A silastic inflatable occluder was placed around the aorta ...
We investigated whether indomethacin, a prostaglandin (PG) synthesis inhibitor, modulates the effect of norepinephrine on the autoregulation of the renal blood flow(RBF) in anesthetized dogs. A silastic inflatable occluder was placed around the aorta cephalad to the bifurcation of thee renal artery, and an electromagnetic flow probe was placed around the renal artery for the measurement of RBF.
RBF autoregulatory curves were determined during intravenous infusion of NE(0.3 & 0.8 ㎍/㎏/min) before and after the blockade of PG synthesis with indomethacin(1-2 ㎎/㎏).
During control, we observed a precise autoregulation of RBF until RAP decreased to 69±3mmHg. The higher dose(0.8 ㎍/㎏/min) of NE shifted the curve to the right increasing the lower limit of RBF autoregulation to 79±5 mmHg while the lower dose had no effect on the curve. Inhibition of PG synthesis with indomethacin decreased RBF 8-10% during basal condition. However, the autoregulatory curves determind after the inhibition of PG synthesis were not significantly different from those determined before the inhibition.
These data indicate that PG does not modulate the effect of norepinephrine on the autoregulation of RBF.