EFFECT OF NORDIHYDROGUAIARETIC ACID ON CEREBRAL BLOOD-FLOW AND METABOLISM DURING HYPOXIA IN NEWBORN PIGLETS

Nordihydroguaiaretic acid (NDGA), a lipoxygenase inhibitor, was invest igated for its effect on cerebral blood flow (CBF) and cortical oxygen consumption during hypoxia in 9 anesthetized, ventilated newborn pigl ets. CBF was measured by radioactive microspheres while brain cortical metabolism was evaluated by continuous P-31-NMR spectroscopy. Five pi glets were treated with NDGA (3 mg/kg i.v. in 50% ethanol as vehicle) prior to hypoxia and had CBF measured before NDGA (control), 15 min af ter NDGA (baseline) and then after 15 and 45 min of hypoxia following NDGA. Another 4 piglets were treated with vehicle (2 ml/kg 50% ethanol ) under the same protocol. In the NDGA-treated piglets, cerebral corti cal O-2 consumption for a given PCr/Pi was significantly increased (p < 0.05) compared to Leukotrienes non-NDGA. Since NDGA inhibits product ion of vasocon-stricting leukotrienes during hypoxia, cortical capilla ry beds Microspheres otherwise constricted may be perfused following N DGA, thus Cerebral metabolism increasing the O-2-consuming tissue area .