EFFECTS OF ISCHEMIA-HYPOXIA INDUCED BY INTERRUPTION OF UTERINE BLOOD-FLOW ON FETAL-RAT LIVER AND BRAIN ENZYME-ACTIVITIES AND OFFSPRING BEHAVIOR

The effects of acute perinatal ischemia-hypoxia on fetal liver and bra in energy metabolism, fetal brain total free fatty acid concentration and subsequent offspring behavior were investigated in rats. Ischemia- hypoxia was induced at term either by ligation of the uterine blood ve ssels or submersion of the entire uterine horn in warmed saline. Fetus es of the adjacent horn served as within-dam controls for all assessme nts and fetuses of dams which had not undergone the surgical stress se rved as independent controls for enzyme assays. Ischemia-hypoxia was a ssociated with reduced activity of fatty acid synthase in the liver an d brain. Total free fatty acid concentration significantly increased i n the fetal hypoxic brain. Pups not used for enzyme analyses were cros s-fostered for behavioral assessments. Relative to the enzymatic alter ations, there were few behavioral alterations associated with ischemia -hypoxia. At postnatal day 30, rats made hypoxic by ligation of the ut erine blood vessels had decreased caudate nucleus and brain stem weigh ts relative to within-dam controls. At postnatal day 85, rats made hyp oxic by submersion of the uterine horn had decreased olfactory bulb we ight. The results of this study indicate an initial acute response to a brief period of ischemia-hypoxia at term pregnancy in the fetal rat brain and liver.