Effects of prolonged infusion of beta-adrenergic agonists on uterine and umbilical blood flow in pregnant sheep.
We have extended our evaluation of the effects of three beta-adrenergic agents in near-term pregnant sheep to include a period of infusion three times longer than previously studied. This extension has provided the following information: (1) Initial depression of uterine blood flow and mean arterial pressure associated with administration of ritodrine or salbutamol abate with time despite continued drug infusion; (2) the uterine hyperemia associated with salbutamol and fenoterol are drug-related rather than postinfusion-related phenomena; (3) increased uterine vascular resistance is found with ritodrine, and decreased uterine vascular resistance occurs with salbutamol and fenoterol.
D000318:Adrenergic beta-Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D000420:Albuterol / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D001769:Blood; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D002245:Carbon Dioxide / Q000097:blood; D005260:Female; D005280:Fenoterol / Q000008:administration & dosage / Q000494:pharmacology; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006863:Hydrogen-Ion Concentration; D007263:Infusions, Parenteral; D008431:Maternal-Fetal Exchange / Q000187:drug effects; D010100:Oxygen / Q000097:blood; D011247:Pregnancy; D012039:Regional Blood Flow / Q000187:drug effects; D012312:Ritodrine / Q000008:administration & dosage / Q000494:pharmacology; D012756:Sheep; D014471:Umbilical Veins / Q000502:physiology*; D014599:Uterus / Q000098:blood supply*
D000318:Adrenergic beta-Agonists; D001786:Blood Glucose; D002245:Carbon Dioxide; D005280:Fenoterol; D012312:Ritodrine; D000420:Albuterol; D010100:Oxygen