The effects of hypoglycin-A on thyroid activity (abstract only)

ABSTRACT

The effects of hypoglycin-A (L-a-amino-á-methylene cyclopropane propprionic acid) the active principle of the fruit blighia sapida, ("ackee"), on the thyroid function of the rat have been studied. At the end of twenty-four hours hypoglycin-A (5-40 mg/kg. body weight) depressed the level of the protein bound iodine (PBI) in the plasma. With doses of hypoglycin-A in the range of 5-10 mg/kg body weight, there is some increase in the urinary excretion of radioactive iodine (131I), while larger doses (20-40 mg/kg) definitely decreased the urinary excretion of 131I. It is assumed the at hypoglycin-A acts on the thyroid function like sodium salycylate in causing an acute decrease in the level of the PBI, and like thiouracil, by causing a decrease deiodination by the liver and the thyroid gland. In a time course study, the effect of hypoglycin-A, 10 mg/kg on injected 131I, there appear to be two active metabolic components of hypoglycin-A, which cause depression of the uptake 131I by the thyroid, kidney and liver, one having an effect within one hour, the other acting four hours after administration. The effect of hypoglycin-A on thyroid function appears not to be specific, but a part of its general antimetabolic action (AU)