Goiter In Rats Research Articles

The effect of certain anions upon the accumulation and retention of iodide by the thyroid gland.

THE goitrogenic action of thiocyanate has been known since 1936 when Barker reported the occurrence of goiter in patients receiving thiocyanate therapy for hypertension and the correction of such goiter by the administration of desiccated thyroid. Astwood later (1943) produced goiter in rats with thiocyanate, but found no goitrogenic effect when iodide was given simultaneously. The action of thiocyanate was poorly understood until Franklin, Chaikoff and Lerner (1944) demonstrated that it interfered with thyroidal accumulation of iodine, in contrast to thiouracil which blocked the organic incorporation of iodine but did not inhibit its collection by the thyroid. In this way the process of iodine accumulation was clearly distinguished from that of hormone synthesis. Vanderlaan and Vanderlaan (1947) and Taurog, Chaikoff and Feller (1947) showed that iodine accumulated by animals treated with propylthiouracil was held in the form of the iodide ion.

THE ACCUMULATION OF RADIOACTIVE IODIDE BY THE THYROID GLAND IN NORMAL AND THYROTOXIC SUBJECTS AND THE EFFECT OF THIOCYANATE ON ITS DISCHARGE1

Interest in the effects of thiocyanate on the thyroid gland followed the observation that goiter occurred in 11 of 246 patients treated with the material for long periods of time for hypertension (Barker, 1936; Barker, Lindberg, and Wald, 1941). Both the thyroid enlargement and the accompanying manifestations of hypothyroidism were relieved by thyroid administration. It was later postulated that the action of thiocyanate in producing goiter in rats differed from that of the thiouracil derivatives (Astwood, 1943). With the former the thyroid effect was much slower to develop and was completely abolished by added iodide, which did not modify the thyroid response to compounds of the thiouracil series. From studies of the accumulation of I131 by surviving thyroid slices from sheep, Franklin, Chaikoff, and Lerner (1944) showed that the iodide-concentrating capacity was inhibited by thiocyanate. Other goitrogens did not significantly diminish the accumulation of iodide by the tissue but prevented its conversion...

THE USE OF THIOURACIL IN THE TREATMENT OF PATIENTS WITH HYPERTHYROIDISM

Excerpt HISTORICAL REVIEW The origin of the use of thiouracil in the treatment of hyperthyroidism stems from the past studies of the mechanism of the production of experimental goiter. During the c...

Production of Goiter in Rats with Raw and with Treated Soy Bean Flour

A diet composed of unprocessed soy bean flour, yeast, sugar, butterfat, sodium chloride and calcium carbonate, when fed to rats, produces thyroid enlargement of four times normal in an experimental period of 7 weeks. The minimum iodine requirement of rats fed the goiterogenic diet is two times normal or approximately 50 μg. per 100 calories of food. The optimum iodine requirement is approximately 200 μg per 1000 calories which is also twice normal. Unprocessed soy bean flour contains a positive goiterogenic property that is removed or destroyed by fat solvents (ether or acetone) or by steam.

THE EFFECTS OF DIETARY DEFICIENCY OF IODIN UPON THE THYROID AND PARATHYROID GLANDS IN THE RAT

There is still difference of opinion concerning the relation between goiter and dietary deficiency of iodin. The literature on the question has been reviewed by Jackson (1, 2) and more recently by Hellwig (3, 4). The production of goiter in rats by low-iodin diets has been claimed by Hayden, Wenner and Rucker (5), Tanabe (6), and Krauss and Monroe (7). On the other hand, Hellwig (3, 4) has recently obtained only negative results. Further study of the question therefore appears desirable. The present experiments extended over a considerable period of time, with careful attention to the diet and to the technique of determining the effects upon the size and structure of the thyroid gland. Observations were made also upon the parathyroid glands.

Production of Goiter in Rats by Restricted Iodin Feeding

Production of Goiter in Rats by Restricted Iodin Feeding

Production of goiter in rats by restricted iodin feeding.

Two litters of white rats were divided, half of each being placed in a separate cage. They were all fed the following diet: 53 parts oats, 25 parts patent flour, 20 parts linseed meal, one part calcium phosphate and one part sodium chloride. In one cage the rats were given distilled water to drink, and the other, water containing 0.1 mg. of iodine per liter. Two rats on each diet were killed after 4 weeks and the weighing of the thyroid completed within 7 minutes after death. This process was repeated every 2 weeks until all had been killed. The following table shows the thyroids to be doubled in size in rats not receiving iodine: