Effect of Potassium Iodide on Basal Metabolism in Guinea Pigs

Abstract

Marine, Deutsch, and Cipra, using an open circuit respiratory calorimeter of the Haldane type, found that KI feeding to 18 normal rabbits caused a drop in the metabolic rate in 5, a slight increase in rate in 2, and no appreciable change in 11. Employing the same apparatus, Webster and Chesney found, following the first dose of Lugol's solution, a decrease in basal metabolism in rabbits, which attained a maximum on the third day, with a subsequent tendency to a return to normal. Cordonnier in our laboratory, using an apparatus devised by Foster and Sundstroem, found that oral administration of KI over a 30 day period produced no appreciable effect on the average basal metabolic rate in 10 normal guinea pigs, though there were individual variations both above and below the normal averages. Loeb, Loeb and Gray, and Rabinovitch, have studied the effects of KI feeding upon compensatory hypertrophy and upon the structure of the thyroid gland in guinea pigs. They found that there is a marked increase in the number of mitotic figures and a slight softening of the colloid, with a slight increase in the height of the epithelium at a certain time during the period of feeding. Inasmuch as the apparatus used by Cordonnier gave somewhat variable results we decided to repeat the study of the effect of KI on basal metabolism in guinea pigs using the Haldane apparatus, which gives much less variable results in control animals. In 8 control guinea pigs weighing between 340 and 500 gm., we found that the basal rate of metabolism of the individual animal, recorded in calories per kilo per hour, varied within ±7.5% of the average rate for that animal.