Recently, many synthetic steroids were reported to be effective as progestational agents. Among these, 17α-methyl-19nortestosterone and 17α-ethynyl-19nortestosterone were the most useful agents for clinnical use. These two steroids, however, showed no progestational effects when they were directly applied in the uterus. And, in addition, apart from the progestational activity, these steroids have been proved to show androgenic and estrogenic activities. Although the effects of these steroids were suggested to be derived from the-metabolites generated in vivo, the metabolism of these steroids was yet unknown. In this experiment, metabolism of these steroids was studied in vivo and in vitro.
The 17α-methyl-19-nortestosterone and 17α-ethynyl-19-nortestostterone were labelled with tritium according to Wilzbach's method.
The labelled 17α-methyl-19-nortestosterone was incubated in vitro with female rat liver homogenate under aerobic conditions. Reduction of ring A was suggested by the decrease of UV absorbing material in the reaction mixture, and the reaction was strongly accelerated by the addition of NADPH in the incubation medium. The extract was chromatographied on paper, and two radioactive metabolites were separated on the paper chromatograph. One was compared with authentic 17α-methyl-19-norandrostane-17β-ol-3-one, and was identified by its mobility on paper, sulfuric acid chromogen spectrum and reactivity with Zimmermann reagent. The other metabolite showed a slightly larger Rf value than 17α-methyl-19-norandrostane-3β, 17β-diol was easily acetylated with acetic anhydride and pyridine. This compound was identified as 17α-methy1-19-norandrostane-3α, 17β-diol from the fact that the oxidized product of this material showed identical properties with the authentic 17α-methyl-19-norandrostane-17β-ol-3-one in the above-mentioned tests.
Similar experiments with 17α-ethynyl-19-nortestosterone showed the conversion of the steroid into 17α-ethynyl-19-norandrostane-17β-ol-3 one and into 17α-ethynyl-19-norandrostane-3α, 17β-diol.
Incubations of these steroids with rat kidndey homogenate showed similar conversion but apparently in a smaller extent than with liver homogenate, and no additional metabolites were obtained.
None of these metabolites showed progestational activity in intrauterine Clauberg assay.
From these data, it was suggested that 17α-methyl-19-nortestosterone and 17α-ethynyl-19-nortestosterone were first reduced in their 4-5 double bond to form 5α-3-ketone and were further reduced in their 3-ketone to form 3-hydroxysteroids. These metabolic fates of drugs were similar to that of testosterone since this compound was reported to be reduced its 4-5 double bond first and then reduced its 3-ketone. Similar conversion has been reported with 19-nortestosterone and 17α-methyl-testosterone.
Androgenic activities of these progestins might be, to some extent, related to their metabolites since the 5a-metabolites of these steroids were known as androgenic substance. But no conclusion could be drawn, from the metabolic fate, on the inefficacy of these drugs applied in utero.

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Recently radioimmunoassay of insulin in the human blood has been developed and reported. In this paper the author has tried to establish an improved method of the radioimmunoassay of insulin in the human serum by using resin, to contribute for routine clinical use in the study of pathophysiology of diabetes mellitus. After a thorough examination of the standard condition, the following assay system was established. Method
To each 10×1.5 cm test tube was added 1.0 ml of increasing dilution of standard insulin or twice-diluted serum, 0.5 ml of 1-131 insulin (17μu) with low specific activity (5 mc/ mg insulin) diluted in 1% albumin solution and 0.5 ml of 1 : 1000 diluted guinea pig antiinsulin serum, making up a total volume of 2 ml. These test tubes were incubated at 2-4°C for 48 hours. After incubation tubes were counted for radioactivity with a well type scintillation counter. This first count was shown as (a). Then a dose of 200 mg of OH-type CG 400 resin was added to each tube, and the test tube was well shaken in a metabiolc shaker at 25°C, 180 cycle/m. for 1 hour. Parafilm was used to cover the test tube. After centrifugation 1.0 ml of supernatant was pipetted and counted for radioactivity. This second count was shown as (b). B/F was obtained from the following formula :
(b) ×2/ (a) - (b) ×2;
where B means immunologically bound insulin and F means free insulin.
Standard curve was drawn from this B/F as vertical and insulin unit (μu) as horizontal indicator. The following methodological studies were carried out in indibidually.
1) Species specificity
Regarding the sensitivity, the method was most sensitive for the assay of beef insulin, because of the use of antiserum for beef insulin and it was followed by human, *porcine, sperm whale and crude human insulin.
2) Dilution of serum
The serum should be diluted 1 : 2 or 1 : 4. But more diluted serum can be used if 1-131 insulin of high specific activity or 1-125 insulin is available.
3) Recovery test was done between 4μu to 70 μu. The amount of 1-131 insulin added was 17 μu. The amount of 4 and 8/tu of insulin added was not recovered but added insulin above 17 pu showed a satisfactory recovery.
4) Reproducibiluty
Some differences were noticed in 6 standard curves drawn in the first 3 months. This indicates that standard curve should be drawn at each experiment.
5) To assure this assay system insulin disappearance test in the dog, cross immunity examinations with other peptide hormones like M.S.H., oxytocin, vasopressin, bovine G.H., ovine lutenizing hormone, thyrotropin, glucagon and porcine ACTH, and insulin destroying test were done, each with satisfactory results. Clinical application of the method was triedon normal subjects and diabetics. The mean fasting insulin of normal human subjects by this method was 29 μu/ml in 20 cases. The variation of serum insulin level in the glucose tolerance test was fairly well paralelled with blood glucose level in normal subjects, whereas delayed insulin secretion in diabetic subjects and almost no insulin secretion in severe diabetics were observed. The principles of the whole method follows the procedure described by Mead and Klitgaard. The important modification and further studies made in the above described method are as follows.
1. An amount of only 0.5 ml of serum was used in each subject to determine the insulin level.
2. The serum should be used in dilution of 1 : 2 or 1 : 4, in this assay system.
3. The precision index of the standard curve was 0.15-0.09.
4. The incubation time of guinea pig antiinsulin serum and insulin was 48 hours.
5. There were some degrees of species specificity proved on account of antiinsulin serum used.
6. The measuring substance was proved to be insulin by 3 experiments.
7. As a conclusion, the author believes this is a simple and convenient insulin assay,

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In the present study the fate of intravenously administered ¹³¹I-human serum albumin has been followed up, and the albumin metabolism in normal subjects, various endocrine disorders, liver diseases and renal diseases were dynamically observed and compared.
Following intravenous administration of 100μC of ¹³¹I-human serum albumin, observations of serum and urinary ¹³¹I were made for 14 to 21 days. Serum volume, rate of intravascular ¹³¹I-human serum albumin, total exchangeable albumin, intravascular and extravascular albumin, degradation rate and synthetic rate of albumin were calculated according to Berson's method.
1). The mean half-life of albumin turnover was 12.5 days in young adults and 12.3 days in middle-aged subjects. But, in elderly subjects it was 16.7 days-a significant prolongation. Albumin synthesis and degradation in elderly subjects were decreased to 65.5% and 63.9% of the values in young adults, respectively.
2.) Acceleration of albumin turnover, that is, an increase in albumin degradation as well as synthesis, in the patients with hyperthyroidism and Cushing's syndrome. In the patients with Cushing's syndrome the decrease in total exchangeable albumin was seen, and this was considered as the result of increase in albumin degradation.
3). In hypothyroidism and Addison's disease the decrease in albumin synthesis and degradation indicative of retaridaton of the albumin turnover were demonstrated. Increase in total exchangeable albumin associated with the increase in extravascular albumin was observed.
4). In acromegaly, total exchangeable albumin was increased consequent on accleration of albumin synthesis.
5). Retardation of albumin turnover in anorexia nervosa was considered to have closely participated in reduced protein or caloric intake.
6). In the cases of chronic hepatitis, synthesis and degradation of albumin and total exchangeable albumin were decreased and it was disclosed that the liver plays an important role in albumin metabolism.
7). The deficiency of albumin in the patients with nephrotic syndrome was due to an increased fractional rate of catabolism of albumin in association with renal losses.

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To clarify the mechanism of anabolic steroid action upon protein metabolism in human subjects dynamic observations of human protein metabolism were made using ¹³¹I-human serum albumin. Healthy subjects, patients with various endocrine disorders, liver diseases and renal diseases were studied. Following intravenous administration of 100μC of ¹³¹I-human serum albumin, observations of serum and urinary ¹³¹I were made for a control period of from 14 to 21 days and anabolic steroids, thyroid hormone or glucocorticoids treatment were begun. One week and six weeks after the beginning of the treatment, patients were restudied by the same loadings and determinations.
1). The patients with normal liver function responded to anabolic steroid treatment with an increase of extravascular as well as total exchangeable albumin, but no change in albumin degradation.
2). In the patients with liver dysfunction, extravascular and total exchangeable albumin did not increase by anabolic steroid treatment and no change was observed in the albumin degradation.
3). The response to anabolic steroid in elderly men was significantly lower than that in young men. From these experiments it may be concluded that anabolic steroid do not inhibit protein catabolism but accelerate synthesis of protein and that the integrity of liver function plays an important role in the acceleration of protein synthesis in the body by anabolic steroids. And moreover, it was suggested that the rate of protein synthesis by anabolic steroids was closely related to caloric intake and dietary protein as the sources of body protein.

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The various types of ”Triiodothyronine (T₃) Suppression Test” were performed on 576 patients (160 with ”Nontoxic Diffuse Goiterh, 205 with”Toxic Diffuse Goiter” and 221 with ”Treated Hyperthyroidismh which consisted of 86 clearly euthyroid, 41 quesionable, 76 clearly hyperthyroid and 8 hypothyroid state).
T₃ was administered orally at a dose of 50 μg. or 100 μg daily. Thyroidal I¹³¹-uptake at 24 hours was evaluated before and on the 3rd, 6th, or 13th day during T₃ administration. The effect of each type of T₄ administration on thyroidal I-¹³¹uptake is expressed as the suppressibility which was calculated by the following formula :
S (%) =U₁-U₂/U₁×100
S : suppressibility
U₁ : thyroidal I¹³¹ uptake before T₃ administration
U₂ : thyroidal I¹³¹ uptake during T₄ administration
1) In the patients with ”Nontoxic Diffuse Goiter”, the mean value of suppressibility was 65.1 % on the 6th day during T₄ administration of 50 μg/day, 48.6% on the 3rd day, 74.0% on the 6th day and 91.4% on the 13th day during T₃ daministration of 100 μg/day, respectively, with the lower limit of normal suppressibility, which was calculated as lower rejection limit of suppressibility, of 15.9% on the 6th day during T₃ administration of 50μg /day, -9.0% on the 3rd day, 35.9% on the 6th day and 73.5% on the 13th day during T₃ administration of 100μg./day which incresed in accordance with an increase of either daily doses or duration of T₃ administration.
2) In the patients with”Toxic Diffuse Goiter”, the mean value of suppressibility in each type of T₃ administration was-3.9% on the 6th day during T₃ administration of 50 μg/day, -16.8% on the 3rd day, 0.3% on the 6th day and 4.0% on the 13th day during T₃ administration of 100/2g./day, respectively, showing low value. In some cases, however, the normal suppressibility was obtained in each group, e.p. 11.1% on the 6th day during T₃ administration of 50 μg. /day, 60.0% on the 3rd day, and 0.9%, on the 6th day during T₃ administration of 100 μg./day, but none on the 13th day during T₃ administration 100 μg./day.
3) In ”Treated Hyperthyroid” patients who were in the clearly euthyroid state, 66.7% of them on the 6th day during T₃ administration of 50 μg. /day 80.0% of them on the 3rd day, 45.4% on the 6th day and 16.0% on the 13th day during T, administration of 100 μg./day revealed the normal suppressibility. There were however, some cases which revealed the normal suppressibility in the patients who were still clearly in the hyperthyroid state, e.p. 27.3% of them on the 6th day during T₃ administration of 50 μg./day, 100% of them in the 3rd day and 2.0% of them on the 6th day during T₃ administration of 100 iig/.day, but none on the 13th day during T₃adminstration of 100 μg. /day. On the 6th day during T₃ administration of 50 μg. /day and on the 6th day during that of 100 μg/day, a case revealed the normal suppressibility only 4 months after the treatment for hyperthy-roidism while there were no cases which revealed the normal suppressibility within 5 years after treatment for hyperthyroidism on the 13th day during T₃ administration of 100 μg./ day.
It seems that the “Triiodothyronine Suppression Test” by giving T₃100 μg./day orally for 14 days is more reliable index of evaluation for the relationship between the hypophysis and thyroid gland than by any other type of T₃ administration employed in this experiment.

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