Isoxsuprine infusion in the rat: alterations in maternal, fetal and neonatal glucose homeostasis.
To determine the mechanism of alteration in glucose homeostasis associated with maternal isoxsuprine administration, isoxsuprine or 0.04 M saline was administered intravenously for 3 hours to term pregnant and age-matched virgin rats. Isoxsuprine infusion significantly increased plasma glucose and insulin concentrations and decreased hepatic glycogen stores in both. Compared to rat pups of saline infused mothers, pups of isoxsuprine infused mothers had significantly elevated plasma glucose concentrations for the first 4 hours of life and plasma insulin concentrations for the first two. Plasma glucose concentrations for the offspring of isoxsuprine treated mothers then decreased significantly and remained so until 16 hours of age. Hepatic glycogen concentrations were significantly less in rat pups of isoxsuprine treated mothers at birth and for the first 4 hours of life. In a limited number of studies, isoxsuprine was present at birth in substantial quantities (80-85% of maternal levels) in the plasma of rat pups of isoxsuprine infused mothers. These data suggest that maternal isoxsuprine therapy mobilizes hepatic glycogen and results in maternal hyperlgycemia. Maternal isoxsuprine infusion may directly deplete fetal hepatic glycogen and result in transient fetal and neonatal hyperglycemia. the in utero depletion of glycogen and possibly, the early stimulation of insulin production may be responsible for the later significant decreases in plasma glucose in the offspring of isoxsuprine treated mothers.
D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism; D001786:Blood Glucose / Q000032:analysis / Q000378:metabolism*; D005260:Female; D005333:Fetus / Q000032:analysis; D006706:Homeostasis; D007328:Insulin / Q000097:blood; D007556:Isoxsuprine / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D008112:Liver Glycogen / Q000032:analysis; D011247:Pregnancy; D051381:Rats
D001786:Blood Glucose; D007328:Insulin; D008112:Liver Glycogen; D007556:Isoxsuprine