Effect of terbutaline sulphate on ovarian, uterine and maternal placental blood flow in the anesthetized guinea pig.

The effect of terbutaline sulphage, a beta-adrenergic agonist, on uteroplacental blood flow was studied in the guinea pig during late pregnancy. Organ blood flows and cardiac output were assessed by the radioactive microsphere technique. Infusion of terbutaline at a rate of 2nmol min-1 kg-1 body weight caused a significant increase in cardiac output and in the perfusion of the uterus and ovaries, but there was no significant alteration in maternal placental blood flow. When the infusion rate was increased tenfold, there was also a significant rise in the blood supply to the bronchi, urinary bladder, kidneys, and adrenal glands. Maternal placental blood flow was not adversely affected even by this large dose of the drug, although there was a significant reduction in the placental share of the cardiac output.