Effect of Fluoride on the Metabolic Activity of Thyroid Slices

Abstract

NaF added to beef thyroid slices increases the oxidation of glucose-l-C14 and glucose-6-C14 to C14O2 and the incorporation of P32-phosphate into phospholipid. NaF also increases the oxidation of glucose-1-C^^ to C14O2 in dog thyroid slices. In beef thyroid homogenates NaF stimulates the activity of adenyl cyclase. However, NaF fails to induce the formation of pseudopods or intracellular colloid droplets. The failure to induce droplets is not due to any inhibitory effect of fluoride since the response to TSH [thyrotropin] was unaffected by F . The significance of these findings in relation to the possible role of cyclic 3'',5''-AMP in controlling thyroid metabolism is discussed.