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GOITRE COMMITTEE. STUDIES ON THE THYKOID: I. Chapter I.—lntroduction. A Goitre Committee has been set up under the auspices of the Medical Research Council with its headquarters in the Otago Medical School in Dunedin. Researches on thyroid problems which have been in progress in the Medical School for many years are in large measure being carried on by this Committee and this report by C. E. Hercus, N. Edson, T. H. Kennedy, and H. D. Purves constitutes the first official publication from the Council on thyroid problems Further investigations on the role which iodine-lack plays in the production of goitre are presented, particularly as regards the level of iodine metabolism as measured by the urinary excretion correlated with the incidence m goitre in various districts in New Zealand and in certain other countries which have been accessible to us One of the objectives of the investigation has been to detect and delme the part which factors other than iodine-lack are playing in the production of goitre. It has also been the ami to determine with more precision the manner in which iodine-lack produces thyroid derangement. The study also presents the „i t f (.pi-tain experiments in goitre prophylaxis. In addition to the financial assistance provided by i. embodied in .hi, stud, which ™> earned o»t before the advent of the Council, and was made possible by financial aid from the Sir John Roberts fund for Medical Research. Chapter 11. Thyroid Physiology and Experimental Goitre. (a) Hercus and Purves (1936) reported results of investigation of goitrogenic activity in Brassicae species in New Zealand. They showed that the seeds of various Brassicae when fed to rats caused hyperplasia hypertrophy, and loss of colloid and iodine from the thyroids 7P Furthei tests have been made with these materials. The diets employed were made up as foUows . Ground seed, 45 ; skim milk, 30 ; maize-meal, 20 ; marmite, 3 ; cod-liver oil, 1 ; sodium chloride, . total the°iodine content of such diets averaged 270 micrograms per kilo, equivalent to approximately 67 micrograms per 1,000 calories. Such a diet is a comparatively iodine-rich one. The duration of each experiment was thirty-days.

Table I.

Table I shows the results obtained. , ~ ~ Of the two seeds not previously tested, one, radish, proved almost inactive, while the other turnip showed the highest activity yet found m this group, producing an enlargement of the thyroid Jo four times the normal size in thirty days. The experience with cabbage-seed shows that there is floss of activity on storage. This loss was almost complete after two years storage. The steaming experiments are interesting since Webster (1932) recorded that steaming enhanced the activity of clbbige-l eaves. Our results show for the seeds a considerable loss of activity from ten minutes' steaming though turnip still retained a moderate activity after steaming. It is proposed to continue these investigations by testing the effect of water, ether and alcohol extracts of active seeds. If active extracts are obtained it is proposed to attempt the isolation of the active substance.

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r)iet J Weight of Thyroid. Activity. Mg. («) S 01^ 1 j 14 Slight. Radish-seed .. . • • • ■ • • • ' jg Old cabbage-seed Ma r ke d. Fresh cabbage-seed .. • • • • • • • • Turnip-seed.. 25 Moderate. (6) Steamed white mustard ••••., " " u Slight Steamed mustard, ether and alcohol extracted .. • • Marked (c) Turnip-seed •• u Sligllt . ' Turnip-seed and iodide • ■ • • Weight of Thyroid. Activity of Diet. | , Steamed Diet. Diet Diet unsteamed. steamed. Mg. Mg. , 24 12 Inactive. (d) Rape-seed .. •• |g \ Activity greatly Cabbage-see . . • • • 21 J reduced. Turnip-seed .. •• •• •• •• J