Effect of pregnenolone 16α Carbonitrile on the activity of the thyroid gland and of the anterior lobe of the hypophysis of the rat; [EFFET DE LA PREGNENOLONE 16α CARBONITRILE SUR L'ACTIVITE DE LA GLANDE THYROIDE ET L'ANTEHYPOPHYSE DU RAT]

Abstract

Pregnenolone 16α carbonitrile (PCN), in daily doses of 20 mg/100 g body weight, exerted a marked stimulative effect on the rat thyroid. The uptake of radioiodine in animals receiving PCN was increased. Chromatographic investigations showed that in PCN treated animals the biosynthesis of thyroid hormones was accelerated. There is evidence of histophysiological activation of the TSH cells of the adenohypophysis. It was concluded that there was no inhibition of the synthesis of thyroid hormones and that activation of the pituitary thyroid axis under the influence of PCN, resulted from alteration of the peripheral metabolism of thyroxin.