Sixty minute's maltose infusion was carried out in normal subjects and diabetics who were diagnosed using the 50 g oral glucose tolerance test. Infusion was performed at the rate of 15 mg/kg/min using 10% maltose solution.
The serum maltose level was gradually increase after the start of the infusion, but no changes in blood sugar, serum IRI or NEFA in both normal subjects and diabetics during the infusion were found.
Serum immunoreactive growth hormone was increased in normal subjects but there was no change in the diabetics.
Results indicated that maltose infusion has no influence on blood sugar, serum IRI and NEFA in diabetics.
Further studies on the effect of maltose to serum GH will be carried out.

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The auther compared the secretory behavoir of hCS with that of hGH in every trimester of pregnancy, before and after delivery. The response of the secretion of hCS and hGH to arginine, insulin, glucose or FFA was also studied.
Serum hCS concentrations were measured by hCS-Kobe radioimmunoassay (double antibodies method) and serum hGH concentrations were detected by hGH radioimmunoassay kit (Dainabot).
Some workers have noted that hCS may interfere with the radioimmunoassay method for estimating serum hGH in pregnant subjects. Therefore, in the preliminary experiment, the standard hCS (hCS-Kobe) or hGH (provided by Dr. Wilhelmi and National Pituitary Agency) was applied to hCS-Kobe double antibodies radioimmunoassay system or hGH double antibodies radioimmunoassay system and the rate of crossreaction at various concentration of both hormones was tested.
The result showed that hCS did not interfere with the hGH-RIA system even at very high concentration such as 10 μg/ml, nor did hGH interfere with the hCS-RIA system at the concentration between 2 ng/ml and 100 ng/ml.
Thus, serum hCS and hGH was measured under various conditions using the hCS-RIA and hGH-RIA systems.
1. Serum hCS and hGH concentrations during pregnancy
Fifty normal pregnant women of every period of gestation or post partum volunteered for this study. Blood samples were obtained at 8 : 00 am. after an overnight fast. HGH concentration remained almost unchanged through the course of pregnancy, but hCS concentration increased along with the progress of pregnancy.
2. Serum hCS and hGH concentrations during labor and in the early period of puerperium
Serum hGH concentrations increased during labor in some cases, but there were no significant changes in other cases. Serum hCS concentrations scarcely changed until the placentae were delivered in all cases. After the placental delivery, the hCS level fell rapidly, and 60 minutes after delivery, its concentration became 1/10 of the value just before delivery.
The half life of hCS was very short (tl/2 =15-19 minutes).
3. Circadian rhythm of hCS and hGH during pregnancy As to the circadian rhythm during pregnancy, hGH showed an apparent peak at 2 : 00 a.m., as was seen in the non-pregnant subjects. HCS, however, showed no definite pattern.
4. Effect of loading test on the concentrations of serum hCS or hGH.
These studies were initiated at 8 : 00 a.m. after an overnight fast. The volunteers in the 2nd and 3rd trimester of pregnancy were placed at bed rest in a quiet room. An antecubital vein was incised and kept open with a slow drip of normal saline. Blood samples weer obtained at 15-30 minutes intervals for a total period of 3 hours before, during and after the stimuli.
A. Arginine loading test
L-arginine infusion of 0.5 gram per kilogram of body weight over a 30 minute period was initiated after one hour baseline studies. The hGH concentration increased at 30 to 45 minutes after arginine infusion. This response was markedly lower than that of non-pregnant subjects. During the arginine loading test there was no significant change in hCS concentration.
B. Insulin loading test
Regular insulin was given intravenously in a dose of 0.1 IU per kilogram of body weight. There was a peak level of hGH at 45 to 90 minutes after insulin loading, but there was no significant change in hCS concentration.
C. Glucose loading test
50 grams of glucose was given per os. HGH concentration decreased from 90 to 120 minutes after glucose loading, but there was no significant change in hCS concentration. D. FFA loading test
250 ml of Intrafat (FFA complex) was given intravenously over a period of 90 minutes. Serum hCS and hGH concentrations increased in some cases, but there were no remarkable changes in other cases.
To summarize, hCS and hGH have some similar characteristics biologically, immunologically and immunochemically,

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Buckle and Jones reported that γ-guanidinobutytamide had a hypoglycemic action. The role of γ-guanidinobutyramide in a metabolic pathway involving arginine was studied by Beeson et al. A stimulatory effect of arginine on insulin and glucagon secretion in a presence of glucose was demonstrated by many authors. In the present paper, an experimental effect of γ-guanidinobutyramide was studied in comparison with that of arginine on insulin and glucagon secretion from the perfused rat pancreas.
Male Wistar-albino rats (weighing between 200 and 250g) were fasted for 20 hours before operation. The preparation of the isolated pancreas was made by the modified method of Grodsky. After Nembutal anesthesia, the stomach and spleen were re-moved. One block of the pancreas and the proximal portion of duodenum was taken out. A cannula was inserted into the celiac artery of the preparation. Effluent from the portal vein was collected in test tubes. Krebs-Ringer bicarbonate buffer containing 4.5% dextran was used as the perfusate. The buffer was equilibrated with 95% O₂ and 5% CO₂. The flow rate was adjusted to two ml per minute under a pressure of 50 to 100 mmHg. The temperature of the perfusate was 3° to 38°C. Arginine and γ-guanidinobutyramide was infused via a side arm at a rate of 0.2 ml per minute with a constant infusion pump. Insulin was measured by the method of Morgan and Lazarow. Glucagon was estimated by the method of Buchanan, i.e., ¹²⁵I-glucagon binding to antibody was separated from free ¹²⁵I-glucagon by dextran coated charcoal.
Infusion of arginine at a rate of 1 mg per minute in combination with glucose (50 mg%) produced both insulin and glucagon secretion. The peak of insulin was 32.4±3.2 ng/ml at two minute and that of glucagon 2062±106 pg/ml at the same time. The patterns of insulin and glucagon secretion were monophasic. In the presence of glucoose (150 mg%), arginine produced insulin and glucagon secretion and they reached peak values with 39.0±3.3 ng/ml and 3433±127 pg/ml, respectively. The patterns of insulin and glucagon secretion were diphasic. Oh the contrary, infusion of γ-guanidinobutyramide at a rate of 200 μg per minute in combination with glucose (50 mg%) produced a continuous secretion of insulin over 60 minutes. The secretion of insulin induced by γ-guanidinobutyramide was inhibited by an infusion of adrenergic beta-blocking agent (propranolol, 1 μg per minute). The result suggested that γ-guanidinobutyarmide-induced insulin secretion was modulated by adrenergic beta-receptor. Insulin secretion induced by glucose (150 mg%) was enhanced, when γ-guanidinobutyramide was infused at a rate of 200 μg per minute in combination with glucose (150 mg%). Glucagon secretion was inhibited by γ-guanidinobutyramide in the presence of glucose (50 mg%). However, in thr presence of glucose (150 mg%) γ-guanidinobutyramide did not have any influence on glucagon secretion. In summary, γ-guanidinobutyramide has a stimulatory effect on insulin secretion but an inhibitory effect on glucagon secretion, and this effect is different from that of arginine. Further experimental research is necessary for the explanation of the different actions of arginine and γ-guanidinobutyramide.

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We designed to develope TRH radioimmunoassay for unextracted human urine. Anti-TRH antibody was produced by immunization of rabbit with TRH-bis-diazotizedbovine serum albumin conjugate. The antibody had no crossreactivity with TRH analogues, amino acids or pituitary hormones, but L or DL-Aze3-TRH. TRH radioiodinized by Greenwood-Hunter's method followed by purification procedure on Sephadex G-10.
Inactivation of TRH by serum was well documented. We found urine gave the same kinds of inactivation of TRH which was prevented by acidification of urine or keeping urine below 4C.
All assay procedure was performed in 0.01 M phosphate buffer with 0.15 M NaCl (pH 7.5) at 4C. Free and bound form were separated with second antibody system. In this system, sensitivity was 0.01 ng/tube, recovery was approximately 100%, intraassay reproducibility was 3.2% and interassay variation was 9.8%.
TRH levels in urine measured with this system were undetectable to 9.0 ng/ml in normal subjects, undetectable in hyperthyroid patients or a tertiary hypothyroid patient and 13 to 24 ng/ml in primary hypothyroid patients.
Approximately 6 percent of intravenously administrated TRH was excreted into urine within 12 hours following administration in a normal subject.
From these data this assay system renders attractive for clinical determination and for research application as well.

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The effects of glucagon, NaF, DBcAMP or theophyllin on the insulin-binding capacity were studied with I (125) iodoinsulin, which was shown to be a valid tracer of native insulin. At the same time, the binding of insulin to the various cellular fractions was measured by the decrease in the immunoreactive insulin content of 0.5 ml. of incubation medium following the addition of approximately 1 mg. of cellular protein. The binding of insulin to isolated fat cells was approximately 5 microunts/100 mg when the concentration of insulin in the incubation medium was 100 microunits per ml. The initial step of the insulin receptor interaction followed the law of mass action and it showed suturation process. In the presence of glucagon (100 microgram per ml), the initial step of the insulin receptor interaction showed a time lag of 1 or 2 minutes. The association constant was increased in the presense of DBcAMP (0.25 mM), NaF and glucagon, especially in the presense of NaF (10.7 × 10⁹/M/sec) which was 3.1 × 10⁹/M/sec in control. The maximum binding capacity of fat cells was 56000 molecules of insulin to one cell which was not significantly altered in the presence or absence of glucagon, NaF, DBcAMP or theophyllin, and from these reasons it appears that glucagon, NaF and DBcAMP (0.25 mM) render the insulin receptor system to increase the affinity to insulin.
Insulin binds selectively to the plasma membrane fraction of isolated fat cells, and the binding of insulin to the “microsomal fraction” probably indicates that this fraction contains small particles of plasma membrane origin.

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The effect of thyroid hormone on the secretion of human growth hormone (HGH) was assessed by radioimmunoassay in patients with thyroid disorders and in normal males treated with triiodothyronine (T3), prednisolone (CS) and both drugs. To provoke the release of HGH, two tests; ITT (intravenous injection of 0.1 U./kg b.w. of crystalline insulin) and ATT (infusion of 0, 5 g/kg b.w. of 1-arginine monohydrochioride over a 30-minute period), were employed. To induce a state of factitious hyperthyroidism, 150 μg/d. of T3 were administered for 10 days in normal males, and plasma HGH responses to arginine were evaluated before and after the treatment in comparison with the results obtained by the same studies with prednisolone ((30 mg/d.) and prednisolone plus T3.
Results were as follows :
1) In 8 patients with primary hypothyroidism and 11 thyrotoxic patients, the mean max. levels of HGH in ITT were 3.3, 6.7 μg/ml, respectively, and were significantly lower compared with 14.6 mpg/ml in normal controls. No significant difference was observed in the degree of insulin-induced decrease of blood sugar between the patients and normal controls. In 11 patients with hypothyroidism and 16 thyrotoxic patients, the mean max. levels of HGH in ATT were 3.2, 8.1 μg/ml, respectively, and were also significantly lower compared with 18.6 μg/ml in normal controls. When euthyroid states were brought about with treatment in both hypothyroidism and hyperthyroidism, the HGH responses to arginine improved to the mean max. levels 14.2, 13.9 μg/ml, respectively, but these values were still considerably lower than those in normal controls. Five thyrotoxic patients with glucose intolerance showed higher response to insulin-induced hypoglycemia and lower one to arginine than the thyrotoxics with normal glucose tolerance.
2) In thyrotoxic patients, max. level and max. increment of HGH in ITT and ATT were not correlated with serum thyroxine levels, degree of clinical severity, and duration of the illness and other laboratory data.
3) After treatment with T3 in 11 male subjects, the mean max. level and mean max. increment of HGH response to arginine were significantly suppressed (p<0.01), being 61% and 64% of those in control studies, respectively.
On CS administration, the same degree of suppressive effect on HGH responses to arginine was demonstrated.
The combined administration of T3 and CS showed the most suppressive effect on HGH responses to arginine.
4) From these results it was suggested that, under the conditions employed in this study, T3 induced the decrease in the HGH response to arginine probably through a direct action on the pituitary or a higher regulating mechanism of HGH secretion.
An additional factor other than the above-mentioned direct mechanism for the defective secretion of HGH in hyperthyroidism, there is a possibility that long-standing excess of thyroid hormone affects metabolic homeostasis and in turn the regulatory mechanism of HGH including the central nervous system.

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The existence of a relationship between the propionate metabolism and TCA cycle the influence of starvation and alloxan treatment on the propionate metabolism, and the relationships between the propionate metabolism and glycolysis changed by alloxan treatment in the liver slices of ruminants is reported. Further study was designed to elucidate the relationship between the propionate metabolism and TCA cycle, and how this relationship was influenced by the starvation and alloxan treatment in liver, slices of sheep. The following results were obtained in a study on the influence of citrate or succinate on the ¹⁴C-propionate metabolism and of propionate on the metabolism ¹⁴C-citrate or ¹⁴C-succinate in the liver slices of normally fed, starved and alloxan diabetic sheep.
In the liver slices of normally fed and starved sheep, the transfer of ¹⁴C from ¹⁴C-1-propionate and ¹⁴C-2-propionate (¹⁴C-propionate) into CO₂, cholesterol, triglyceride and phospholipid was increased and the formation of ¹⁴C-glucose and ¹⁴C-NEFA from ¹⁴C-propionate was decrased by the addition of citrate and succinate, and the transfer of ¹⁴C form ¹⁴C-1, 5-citrate (¹⁴C-cirtate) or ¹⁴C-1, 4-succinate (¹⁴C-succinate) into CO₂, ketone bodies and cholesterol was decreased. The formation of ¹⁴C-NEFA and ¹⁴C-phospholipid from ¹⁴C-citrate or ¹⁴C-succinate was increased by the addition of propionate.
Furthermore, the citrate effects on the propionate metabolism and the propionate effects on the citrate metabolism disappeared with the alloxan treatment. However the succinate effects on the propionate metabolism and the propionate effects on the succinate metabolism were observed in the liver slices of alloxan diabetic animals.
As mentioned above, there were some relationships between the propionate metabolism and TCA cycle, and these relationships were changed by the alloxan treatment in the liver slices of sheep.

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