Oxygen consumption and phosphorylation of beef thyroid slices were determined in vitro in the presence of thiocyanate at concentrations ranging from 10^-2M to 10^-7M. Iodide uptake and its organic binding were also measured under similar experimental conditions.
Thiocyanate increased oxygen consumption and decreased phosphorylation and rate of oxidative phosphorylation of the thyroid at concentrations above 10^-4M. In the same concentration range, thiocvanate depressed the uptake of I¹³¹ by the thyroid.
From the evidence presented, it was inferred that thiocyanate exerted its action of depressing iodide concentration of the thyroid through energetical mechanism, that is, through depression of much, if not all, of the energy supplied by highenergy phosphate bonds for the active transfer and maintenance of concentration gradient of inorganic iodide by the thyroid tissue.

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The case represented in this paper is a sixty years old diabetic patient whose retinopathy appeared after the administration of insulin although his diabetic symptoms disappeared. We think this manifestation of diabetic retinopathy after insulin treatment is due to the increased release of corticosteroids, reacting to the hypoglycemia induced by overdosage of insulin.

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In order to investigate the hypothalamic control of lactation, bilateral electrolytic lesions were given stereotaxically in the hypothalamus of lactating rats.
Lactational performance of these rats bearing hypothalamic lesions were estimated mainly by litter growth curves.
The animals recovered quickly from the operation and were in good condition and they were divided into the following 2 groups on the basis of the location of the lesions: 1. animals with anterior hypothalamic lesions (Group A), 2. animals with lesions of the medial part of the hypothalami (Group M). Each group was classified into 2 subgroups according to their ability to rear their young. The regression coefficient of the growth curve of the litters of the animals which reared their young in both Groups A and M was significantly lower than those of the normal and sham operated groups.
The litters, of the animals which failed to rear their young, lost their weight gradually and died within 7 days after the operation and no milk was found in their stomachs in spite of their vigorous suckling;however, milk could be squeezed from the mother's teats even 10 days after the operation.
A lactational vaginal smear was obtained whenever suckling lasted, and after cessation of the suckling stimulus an oestrous smear reappeared within a few days.
These findings imply the possibility of selective impairment of the part of the hypothalamus, which is linked to the secretion of oxytocin.

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1. The oxygen consumption of beef thyroid slices in Krebs-Ringer phosphate solution containing carrier free Nal¹³¹ was measured. After incubation, thyroid slices were digested and iodine fractions of hydrolysate were determined by paperchromatography.
2. Estradiol suppressed oxygen consumption, inorganic I¹³¹ uptake and organic binding of iodide of thyroid slices at the higher concentration, 10^-4M. While, at the lower concentration, around 10^-6M, the hormone slightly stimulated hormonogenesis.
3. Progesterone showed an inhibiting effect on hormonogenesis of thyroid slices at higher concentrations, 10^-3 and 10^-4M but not so profoundly as estradiol, when both effects were compared in same molar concentration. At the lower concentration, 10^-6M, the inhibiting effect was absent.
4. Cholesterol at the concentration of 10^-4M, used as a control substance of steroid compound, had no effect on hormonogenesis of thyroid slices.
5. Estradiol and progesterone at concentrations of 10^-4 and 10^-6M did not show significant effect on oxidative phosphorylation of thyroid slices.
6. From the data obtained in this study, the role of the hormones in the physiology of the thyroid gland is discussed in view of the results obtained in in vivo experiments.

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(1) After placing the lesions in the anterior, middle and posterior hypothalamus of rats with the Krieg's stereotaxic machine, and the apparatus devised by the Brain Research Institute of Tokyo University, MTU or TRF was administered for 3 and 5 consecutive weeks, and the weight of pituitary and thyroid, I¹³¹ uptake of the thyroid, T/S ratio of I¹³¹ concentration and the histological changes in thyroid and hypophysis were investigated.
(2) When the lesions extended from the rostrum of the median eminence to the frontal area in the hypothalamus, both the thyroid and the pituitary weight decreased, the thyroidal function was slightly depressed, and the goitrogenic response to MTU was prevented. However, when TRF was given, the weight and function of the thyroid remarkably increased.
(3) When the lesions were placed in the middle and posterior hypothalamus, scarcely any depression was observed either morphologically or functionally. Depression was seen only when the lesions involved the median eminence. The goitrogenic effect of MTU was evidently observed. The administration of TRF produced both morphological and functional activation of the thyroid together with enlargement of the hypophysis.
(4) A minute (0.2cc), small (0.5cc), medium (1.0cc) and large dose (2.0cc) of TRF were given to both intact rats and those with effective lesions in the anterior hypothalamus. In the case of the minute and small dose a remarkable increase was not seen in the weight of the thyroid and the uptake of the thyroid, but the increase was observed only in the case of the medium and the large dose. By contrast, T/S I¹³¹ accumulation ratio was evidently increased by the minute dose, and the increase became still more pronounced when larger doses were given.
(5) It was discussed that the regulatory factor of TSH secretion would be TRF, a neurohumor elaborated in the anterior hypothalamus and excreted in urine.

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Effects of MAD on rats under various conditions, particulary on thyroidectomized ones, were studied with special reference to the difference in growth between males and females.
1) When administration of 0.4mg/kg of MAD was started at 48 hrs. interval at the 4th week of age, simultaneously with thyroidectomy, depression of the growth of male rat and the acceleration of growth in the female were observed.
2) When the treatment of MAD had been commenced at the 1st week of age prior to the thyroidectomy conducted at the 4th week of age, the depression of male growth could not be observed, although the enhancement of female growth remained similar. Cessation of MAD administration at the 4th week of age did not bring an essential change to these results.
3) MAD treatment by itself did not exert a significant influence on the growth of intact rats, when given in a dose of 0.4mg/kg at 48 hrs, interval. In a does of 4 ing/kg, however, MAD decreased the male growth but increased the female growth.
4) The effect of MAD on castrated rat, in which the superiority of male to female in body weight had already been reduced considerably, was also similar to that on the intact rat, i. e., the difference between male and female became still smaller, if such a higher dose as 4mg/kg was administered.
5) MAD in a dose of 4 mg/kg at 48 hrs. interval, commenced simultaneously with hypophysectomy, showed a marked increase in growth of hypophysectomized rats, irrespective of sex, if operation was conducted at the 5th week of age, whereas no significant effect was observed in those operated at the 7th week of age.
In conclusion, MAD showed an inhibitory effect on male growth and a stimulating effect on female growth. The absence of thyroid gland and/or reproductive organ, especially the former, seemed to enhance this trend.

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Using I¹³¹-labeled casein as substrate, the presence of proteolytic activity in human saliva was demonstrated, by measuring the increase of the radioactivity in the non-protein fraction of the incubation mixture and also by employing the so-called quantitative radio-paperchromatography.
This proteolytic activity of saliva had its optimal pH between 6 and 8. It was fairly stable at pH 7.2 and 37°C, but was completely inactivated by heating the saliva in boiling water for 30 mins.
Besides the proteolytic activity, human saliva was found to possess the activity to prevent the precipitation of relatively small amounts of easily precipitable protein by TCA (“anti-TCA activity”), for which salivary mucoid or its related substanc was presumed to be responsible.
Considerably large variations in proteolytic and anti-TCA activities of saliva were observed from person to person as well as from day to day.

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