The insulin delivery rates were estimated in 8 normal and 8 diabetic subjects from the results of peripheral insulin response to a single bolus iv injection of glucose, taking account of fractionally removed insulin. The delivered insulin response to 0.5g/Kg body weight of glucose injection was biphasic in normal and diabetic subjects. In normal subjects, 1.7±0.3 U of insulin was delivered during the first phase (0-10min) and 5.6±1.6 U during the second phase (11-60 min). In diabetic subjects, 0.4±0.2 U of insulin was delivered during the first phase and 1.8±0.5U during the second phase. The amounts of delivered insulin during the first and second phases were significantly decreased in diabetics (p<0.01). The insulin delivery rates during the first and second phases fitted by the same line to the glucose concentration at each period. This suggests that a common glucoreceptor or glucosemediated signal of the insulin response might exist during both phases. The glucoseinsulin response curves in mild diabetics seemed to be similar to those in the normals, but shifted toward higher glucose levels. This finding suggests that the decreased glucose sensitivity of pancreatic beta cells in mild diabetics can be corrected by high glucose concentrations.

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Effects of somatostatin on extrapancreatic glucagon secretion in totally depancreatized dogs were examined. Somatostatin infusion at a rate of 3μg/min showed a rapid decrease of total glucagon-like immunoreactive materials (total GLI) measured by nonspecific antiserum, AGS 10, and gut glucagon immunoreactivity (gut GI) measured by specific antiserum, AGS 18, in systemic blood. Gut GLI calculated as the difference between total GLI and GI did not decrease significantly within 30min. No changes of blood glucose were noted. Significant decreases of all glucagon fractions were observed when the rate of somatostatin infusion was increased to 10μg/min and prolonged for 90min, whereas again blood glucose did not change at all. It is concluded that somatostatin inhibits both gut GI and GLI secretion, although gut GLI remains in circulation longer than gut GI. Suppression of gut GI is not effective for the reduction of blood glucose once an extreme hyperglycemia is brought about by insulin deficiency.

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The effect of calcitonin (CT) on the serum and liver calcium is examined in rats ligated the bile duct. The subcutaneous administration of CT (80 MRC mU/100g BW) significantly prevented the increase of serum calcium concentration after a single oral injection of calcium (50mg/100g BW) to sham-operated rats. But the ligation of bile duct prevented the hypocalcemic effect of CT. Meanwhile, CT significantly increased the liver calcium content after the calcium injection to sham-operated rats. However, the liver calcium content after CT administration was markedly elevated by the ligation of bile duct in comparison with that of sham-operated rats. The present results suggest that the liver calcium increased by CT administration secretes into the bile.

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Repeated treatments of the liver cytosol prelabeled with ³H-dexamethasone with DNA-cellulose followed by treatments with purified liver nuclei enabled us to assess the amount of two forms of dexamethasone-receptor complex, one binds only to nuclei and the other binds to DNA and nuclei. The comparable amount of these two forms of the receptor complex was detected in the dexamethasone-labeled liver cytosol, while only one form which binds only to nuclei was found in the liver cytosol labeled with antiglucocorticoid, cortexolone. The significant amount of receptor complex which binds to DNA and nuclei was not present in the cytosol from the ventral prostate preincubated with 3H-dihydrotestosterone.

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To clarify the function of ACTH receptors, the actions of ACTH on cyclic AMP formation, Ca²⁺-influx across cell membrane, and corticoidogenesis were examined using dispersed adrenocortical cells prepared from the rat adrenal gland.
1) There are two types of ACTH receptors from Scatchard analysis of ¹²⁵I-ACTH_1-24 binding to the cell, the one receptor is of high affinity and low capacity (dissociation constant (Kd₁)=2.6×10^-10M and 7, 350 sites per cell), and the other one is of low affinity and high capacity (dissociation constant (Kd₂)=7.1×10^-9M and 57, 400 sites per cell). 2) Both apparent dissociation constants derived from the effects of ACTH on corticoidogenesis and Ca²⁺-influx well correspond with Kd₁ of the high affinity receptor. 3) Apparent dissociation constant obtained from the effect of ACTH on cyclic AMP formation is in good agreement with Kd₂ of the low affinity receptor.
Thus it could be deduced from these data that the high affinity receptor is concerned with an increased Ca²⁺-influx to regulate corticoidogenesis at physiological levels of ACTH, whereas the low affinity receptor is coupled to adenylate cyclase at supraphysiological concentrations of ACTH.

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Na-sulfacetylthiazole (SAT), 0.1g/kg body weight as 5% aqueous solution, was injected intraperitoneally to Wistar male rats weighing 200 to 300g, twice a week for 1, 2 and 4 months, while 1 α-hydroxy vitamin D₃ (1α-OH-D₃) was simultaneously administered orally to a half of the SAT-4 month-treated rats at a daily dose of 0.25αg/kg body weight for the last 19 days of the feeding period. Both blood urea nitrogen (BUN) and serum inorganic phosphorus concentrations were markedly increased and the histological examination of the kidneys of SAT-treated rats revealed interstitial nephritis. Serum calcium level was significantly decreased in the rats treated with SAT for 2 or 4 months. Serum parathyroid hormone (PTH) level as well as the wet weight of parathyroid glands was increased in SAT-treated rats, while simultaneous administration of la-OH-D₃ inhibited such increases. Serum 25-hydroxyvitamin D₃ (25-OH-D₃) was decreased in the rats treated with SAT for 2 months. The X-ray density and calcium content of the femurs of SAT-treated rats were decreased, while simultaneous administration of lα-OH-D₃ inhibited such decreases. Tetrachrome stain of the femurs of SAT-4 month-treated rats revealed a marked increase of osteoid contents in the bone cortex, while 1α-OH-D₃ inhibited such an increase in osteoid formation. These data indicate that 1α-OH-D₃ would be effective for the treatment of uremic renal osteodystrophy, although its detailed mechanism remains to be further clarified.

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In a previous experiment, differences in the binding affinity to dexamethasone (DEX) of the cytoplasmic receptor in the fetal and adult rats were observed. Therefore, the binding characteristics of cytoplasmic receptor, to DEX in livers of adult and fetal rats were further examined to throw insight into the mechanism of agerelated changes in responsiveness to glucocorticoids. Cytoplasmic DEX-receptor complexes in both adult and fetal livers were mainly precipitated with 35% saturation of (NH₄) ₂SO₄ and eluted immediately after a void volume from a Sephadex G-100 column. When the 35% ammonium sulfate fraction was applied to DEAE chromatography, two peaks of the radioactivity bound to protein, eluted with 50mM and 100 mM KCl, were observed in the adult liver. On the other hand, only one peak which was eluted with 50mM KCl was noticed in the fetal liver. Stability of the DEX-receptor complex during incubation at 0 or 23 °C was not significantly different in these two tissues. At least two DEX-binding components which exhibited RBPB 0.28 and RBPB 0.43 in polyacrylamide gel electrophoresis were demonstrated in the cytoplasm from the adult liver, while one clear peak with RBPB 0.25 was observed in thefetal liver. The binding in the adult cytosol to DEX was efficiently inhibited by addition of corticosterone and cortisol and the similar inhibition by these two steroids was observed in the binding of fetal cytosol but in the latter tissue, deoxycorticosterone and progesterone were also competed with DEX binding moderately. Two forms of DEX-receptor complex-one binds only to nuclei and the other binds to DNA and nuclei-were observed in the fetal liver cytosol as well as in the adult one. The binding capacity of these two forms of receptor was almost comparable in cytosols of two tissues examined. The nuclear binding of ³H-DEX in the isolated liver cells was also different in fetal and adult animals.

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In order to evaluate the luteotropic effect of human chorionic gonadotropin (HCG) on the human corpus luteum, HCG was administered at the menstrual luteal phase and early gestation. Serum progesterone (P) and estradiol (E₂) levels were compared after determination by radioimmunoassay.
At the mid-luteal phase, although E2 secretion did not increase significantly, Psecre tion showed a significant increase and peaked 6-8 hr after intravenous injection of 20, 000 IU HCG. Three intramuscular injections of 5, 000 IU HCG were administered every other day. An increase in sex steroid production and prolongation of luteal span occurred when HCG was administered in the+7 to+11 day period (following LH peak), rather than the+3 to+7 day period. During early pregnancy (from 5 to 10 weeks' gestation) in threatened abortion cases followed by either normal continuation of pregnancy or abortion, neither a single high dosage of HCG (20, 000 to 100, 000 IU) nor 20, 000 IU per day for 7 days produced any significant change in sex steroid secretion.
From these observations, it is likely that exogenous HCG shows a luteotropic effect on the human corpus luteum during menstruation, but not during gestation.

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The cross-sectional study was undertaken to investigate the correlation of serum gonadotropin levels with physical signs of puberty and also to assess the role of genetic factors in the onset and progression of puberty. Serum concentrations of FSH, LH and prolactin were measured by double antibody radioimmunoassay in 195 monozygotic and 59 dizygotic twin pairs during the years of puberty (12 to 15 years). In boys, serum FSH, LH and prolactin concentrations showed a tendency to increase steadily alone with bone ages (9 to 17 years). The size of testis correlated fairly well with serum LH levels and to some extent with FSH. In the pubic hair stage, a significant difference was observed in serum FSH and LH levels between the groups of PH 1-2 and PH 3<. In girls, serum FSH levels significantly increased in the early phase of puberty and no further increase occurred thereafter, while serum LH and prolactin levels showed an increasing trend with the advance of bone ages to adult levels. As to breast development, serum LH levels alone increased during the early stages of development. When a comparison was made between pre-and postmenarchial groups or between pubic hair stages, a significant difference was present only in LH levels in either comparison.
From a viewpoint of twin zygosity, the intrapair differences of serum gonadotropin levels were compared between monozygotic and dizygotic pairs of twins. Serum LH levels in both sexes and serum FSH in girls of monozygotic pairs of twins showed a significant within-pair similarity compared with dizygotic pairs of twins. Since serum LH levels appeared to have a close relationship with the advancement of puberty in both sexes, these findings suggest that genetic factors play an important role in the onset and progression of individual puberty.

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Urinary kallikrein in a patient with Bartter's syndrome was remarkably higher than normal. Indomethacin treatments increased serum potassium concentration and urinary Na/K ratio, and improved the response of blood pressure to angiotensin II infusion, while it decreased plasma renin activity, plasma aldosterone and urinary kallikrein.
The purified urinary kallikrein had one component of the iso-electric point 4.3 by isoelectric focusing using Ampholine system, and its molecular weight was 4.2×10⁴, which was greater than those of three components of normal human urinary kallikreins (normal HUK). Also Km values with TAME and BAME of urinary kallikrein in our patient with Bartter's syndrome did not correspond to those of normal HUK. Thus it can be said that urinary kallikrein in our patient with Bartter's syndrome was qualitatively different from normal HUK. The present observation might be a reflection of renal tubular dysfunction in this patient with Bartter's syndrome.

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Effect of vasopressin on intracranial pressure (ICP) was examined by an intraventricular administration of the hormone to a rabbit. ICP was determined at the cisterna magna with a manometer and recorded automatically with a recorder. An injection of over 150 μU of vasopressin lowered ICP, but there was no clear doseresponse relationship of the effect of vasopressin on ICP. When vasopressin was injected intraventricularly after lowering ICP by an intravenous injection of acetazolamide which inhibits the production of cerebrospinal fluid (CSF), an additive effect of the hormone on ICP was observed. The effect of vasopressin on excretion of water in CSF was examined by the determination of drainage of tritiated water injected into the lateral ventricle of a rabbit. Drainage of radioactive water into vein was measured by collection of blood at the internal jugular vein and radioactivity of the plasma was counted. Vasopressin accelerated excretion of tritiated water into vein. These results indicate that vasopressin facilitated drainage of CSF into vein to lower ICP.

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Binding of ¹²⁵I-insulin was detected by the polyethylene glycol method in three patients with Hashimoto's thyroiditis, who had very high titers of anti-thyroglobulin and anti-thyroid microsome antibodies. The specificity of this binding was analyzed. In contrast to serum of an insulin-treated diabetic patient which bound only ¹²⁵Iinsulin, these sera bound various ¹²⁵I-labelled peptides (insulin, C-peptide, gastrin, GH, prolactin and TSH) more than normal. The binding of ¹²⁵I-insulin by serum of the insulin-treated patient was inhibited by insulin and iodinated insulin. On the other hand, ¹²⁵I-insulin binding by sera of thyroiditis patients was decreased by the addition of iodinated insulin, iodinated albumin, thyroglobulin, MIT and DIT, but not by unlabelled insulin. Immunization of guinea pigs with thyroglobulin resulted in the production of antisera which bound ¹²⁵I-insulin, and this binding was inhibited by iodinated peptides, MIT and DIT, but not by unlabelled insulin. Binding of ¹²⁵I-insulin by sera of thyroiditis patients was not clearly demonstrated by gel filtration or paper hydrodynamic flow methods, suggesting the weakness of the binding.
These findings suggest that serum ¹²⁵I-insulin binding in Hashimoto's thyroiditis is not due to insulin antibody but due to some other factor, possibly to anti-thyroglobulin antibody with binding specificity to iodotyrosine residues. Such a binding could be a pitfall for the detection of hormone antibodies using radioiodinated hormones, as well as a source of error in some radioimmunoassays.
Serum of a patient with Graves' disease also bound ¹²⁵I-insulin but not the other iodinated peptides and the binding was inhibited to some extent both by unlabelled insulin and by iodinated compounds. The nature of this binding remains obscure.

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In order to investigate the sequence of events concerning gonadotropin surge, serum LH, FSH and estradiol concentrations were measured during the rat estrous cycle as well as hypothalamic and blood levels of LH-RH in the preovulatory stage. Normally cyclic female Wistar rats kept on 12 hr light (from 22.00 hr to 10.00 hr) and 12 hr dark were killed at different times of day during each stage of the cycle. The hypothalamus was quickly dissected out, divided into 3 portions (the anterior, middle and posterior) and extracted in 90% methanol. Blood LH-RH was extracted by affinity chromatography prior to radioimmunoassay. The content of LH-RH in the anterior and middle hypothalamus started to decrease between 1.00hr-3.00hr, reached its nadir at 6.00hr on proestrus and recovered to its previous values on estrus. Almost simultaneously blood LH-RH concentration showed an increase of 18.3 pg/ml- 8.8 pg/ml between 1.00hr-3.00hr, and then fell to<1.0pg/ml at 6.00 hr. On the other hand, serum estradiol level began to elevate on diestrus II followed by its peak at 6.00hr on proestrus, while the peaks of serum LH and FSH were observed at 8.00 hr and 10.00hr, respectively. These studies indicate that the elevation of serum estradiol was followed by the release of LH-RH from the hypothalamus and the LH-RH may be responsible for the preovulatory discharge of gonadotropin.

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In order to examine the dexamethasone suppressibility of plasma pregnenolone, 9 a.m. and overnight suppression tests were performed in normal adult subjects and plasma pregnenolone levels were radioimmunoassayed. The results were as follows: 1) In the 9 a.m. test, plasma pregnenolone was suppressed to the lowest level at the time between 30min and 2 hr after dexamethasone; 2) there was no significant difference in dexamethasone suppressibility of plasma pregnenolone between the 9 a.m. test and overnight test; 3) there was no significant difference from each other among the plasma pregnenolone levels after dexamethasone administration (0.5mg to 3mg) in both tests; 4) after dexamethasone administration, plasma pregnenolone was not suppressed below 40% of the basal level in both tests; 5) discussions were made about the results, comparing with those of the suppressibility of cortisol which were previously reported from this laboratory.

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Application of synthetic human calcitonin analogue ([Asu^{1, 7}]-hCT) was attempted, since it is chemically more stable than native hCT.[Asu^{1, 7}]-hCT was successfully labeled with ¹²⁵I to a specific activity ranging from 410 to 540μCi/μg.
Sensitivity, recovery and reproducibility of the assay system using ¹²⁵I-labeled [Asu^{l, 7}]-hCT analogue, standard synthetic hCT and its antibodies, were 49pg/ml, 99.8±4%, and 7.95%(C. V. within assay) or 21.9%(C. V. between assays), respectively. The dilution curve of the sera obtained from patients with medullary carcinoma paralled well with the standard curve. ¹²⁵I-labeled [Asu^{l, 7}]-hCT analogue can be used for routine radioimmunoassay of hCT.

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A 57-year old woman with thyroid carcinoma manifesting overt thyrotoxicosis is presented. After the patient had been made euthyroid with propylthiouracil, right lobectomy and lymph node dissection were performed. Permanent paraffin sections revealed follicular adenocarcinoma with capsular and vascular invasion. Metastases to the right humerus, both femurs, the skull and pleural cavity became prominent with the recurrence of thyrotoxicosis and the patient died 2 years and 3 months after operation. The clinical evidence indicates that thyrotoxicosis in the present case is caused by the excessive secretion of thyroid hormone by both the original carcinoma and the secondary deposits. Twenty three similar cases reported in the English and Japanese literatures are summarized.

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A female patient with classical gonadal dysgenesis associated with Graves' disease is reported. The karyotype was mosaicism of 45, X/46, X, i (Xq). The relationship among Graves' disease, Hashimoto's thyroiditis and Turner's syndrome is discussed along with a review of the reported cases.

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A comparison was made between the thyrotropin (TSH) response to 500 μg thyrotropin-releasing hormone (TRH) in summer and that in winter in ten healthy normal adults living in Supporo. The serum resin triiodothyronine (T₃) uptake (RT3U), thyroxine (T₄) and T₃ levels were also measured. While the TSH response to TRH in summer was similar to that in winter, serum T3 concentration and free T₃ index were significantly higher in winter than in summer, associated with the similar values in RT3U and T₄ levels in serum. Independently measured 86 specimens (43 in summer and 43 in winter) from normal adults living in the same district also showed a significant increase in serum free T₃ index as well as a slight elevation of serum T₃ concentration in winter but not in serum T₄ level. These results indicate that the primary change in cold winter would be the stimulation of peripheral conversion of T₄ to T₃ rather than the activation of hypothalamo-pituitary-thyroid axis. The relevance of this interpretation was discussed.

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The role of thyrotropin-releasing hormone (TRH) in the secretion of TSH from the anterior pituitary was investigated in rats by active and passive immunization with TRH.
The plasma TSH response to propylthiouracil (PTU) in TRH-bovine serum albumin (BSA)-immunized rats was significantly lower than that of BSA-immunized or non-immunized rats. Similarly, the increased plasma TSH level following PTU treatment was significantly suppressed after iv injection of antiserum to TRH. However, the decline in plasma TSH levels was not complete.
The results of the present study indicate, at least in part, the physiological significance of endogenous TRH in the regulation of pituitary TSH secretion.

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Oral glucose tolerance test with 50g glucose was carried out with and without simultaneous oral administration of 3g calcium lactate. Blood sugar and serum immunoreactive insulin (IRI) were measured before and 30, 60, 90 and 120min after glucose load in 11 diabetics and 11 non-diabetics. Similar oral glucose tolerance test was performed with and without intravenous administration of 10ml 8.5% calcium gluconate in 6 diabetics and 6 non-diabetics. Maximum serum level after glucose load (Max IRI), maximum rise of serum IRI following glucose load (Max ΔIRI), maximumΔIRI/ΔBS following oralglu cose load (Max ΔIRI/ΔBS), the area surrounded by the ΔIRI curve and the abscissa (ΣΔIRI) and the area surrounded by the ΔIRI/ΔBS curve and the atscissa (ΣΔIRI/ΔBS) significantly increased in diabetics but not in non-diabetics after oral calcium load, whereas intravenous calcium load failed to influence any of these values. Oral calcium load thus appears to augment glucose-induced insulin secretion only in diabetics, suggesting some abnormality in the mechanism of insulin secretion with reference to calcium in diabetes mellitus.

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