In order to elucidate the glucoreceptor mechanism involved in insulin release and the character of insulin release under various cationic environments, we have studied the dynamics of insulin release from the rat pancreas perfused with K+, Rb+ and Li+ media (6.2, 24.8 mM) in the presence of glucose and in its absence. The results are as follows.
1. Perfusion in K+, Li-free medium and, 6.2 mM K+, Rb+ or Li+ medium: Insulin release in the second phase occurred in K+, Lit-free, and 6.2 mM Li+ media without glucose, but infusion of 6.2 mM K+ or Rb+ medium did not induce insulin release. Insulin response to infusion of K+, Li-free medium containing 10 mM theophylline was 3 times as large as that of the control in the absence of glucose, but 10 mM theophylline did not affect insulin release in a 6.2 mM Li+ medium. Analysis of Hill plots of rates of insulin release induced with glucose in various media showed that Km, n (Hill constant) and log K (equilibrium constant between glucoreceptor and glucose) were 6.5mM, 1.4, and -1.1 (K+, Li-free), 5.4 mM, 1.4, and -1.0 (6.2 mM Lit), 8.9 mM, 2.4, and -2.3 (6.2mM K+), and 8.7 mM, 2.3, and -2.1 (6.2 mM Rb+), respectively.
2. Perfusion in 24.8 mM K+, Rb+ or Li+ medium: Infusion of 24.8 mM K+ or Rb+ medium provoked a transient insulin release, but that of 24.8 mM Li+ medium did not induce insulin release. The amount of insulin release due to 24.8 mM K+ stimulation following preperfusion with a 12.4mM Li+ plus 6.2 mM K+ medium decreased to 47% of that of the control.
3. Insulin responses due to 16.7 mM α-and β-D-glucose in 6.2 mM K, Rb+ and Li+ media switched from 6.2 mM K+ medium: The average rate of insulin release and the maximal values were 76+10μU/ml/min and 127±30 itU/ml (the α anomer), and (74±8μU/mlmin) and 120±13μU /ml (the β anomer) in a 6.2 mM K+ medium, 34±14μU/ml/min and 57±18μU/ml (the a anomer), and 33μ±10μU/ml and 69±23 tiU/ml at 6 min (the β anomer), in a 6.2 mM Rb+ medium, 41±13μU/ml/min and 72±19μU/ml (the a anomer), and 121±29μU/ml/min and 193±49μU/ml (the β anomer), respectively.
We conclude that Li+ increased in affinity of the glucoreceptor for glucose to cause more enhanced insulin release than those in 6.2 mM K+ or Rb+ medium, and diminished insulin release as compared to that in a K+, Li-free medium through stabilization of the B cell plasma membrane, and moreover provided a greater stimulation of the β anomer than of the a anomer through a conformational change of the glucoreceptor.

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Changes in serum IRI, CPR and glucose were determined in 18 healthy adults after spraying of porcine crystallin insulin to nasal or sublingual mucous membrane. Ten, 30 or 50 U porcine crystallin insulin was dissolved in 0.1 ml 0.9% NaCl containing 1 % sodium glycocholate ph 7.6. When it was applied to nasal mucous membrane, there were significant decreases in serum glucose and CPR levels. There was a positive correlation between the peak serum IRI levels and doses of insulin applied. However, when it was applied to the sublingual mucous membrane, there were no measurable increases in serum IRI levels.
When sodium glycocholate was omitted, no measurable increas in serum IRI levels was observed. Substitution of sodiun glycocholate with other surface activating agents such as lysozyme chloride, HCO-60, Byco-E, did not facilitate the absorption of insulin at all. Ursodeoxycolate was effective in facilitating absorption of insulin from nasal mucous membrane, but this agent was associated with marked local irritation.
The results showed that significant amount of insulin was absorbed from nasal mucous membrane when it was dissolved in a solution contaning sodium glycocholate. This route of administration of insulin may be useful under certain clinical circumstances.

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Glucose homeostasis is one of the most typical feedback control system. Therefore, the understanding of the individual homeostasis is very important to diagnose its glucose tolerance. This study was designed to investigate the universal and quantitative relationship between glucose tolerance and the dynamic property of insulin secretion.
0.3 g per Kg body weight of glucose as a 40 per cent solution in distilled water were administered intravenously in three minutes into 99 normal subjects, 56 borderline cases and 82 diabetics classified according to 50 g oral glucose tolerance test results. The relationship between blood glucose and insulin concentrations were analyzed with the aid of control theory.
The following results were obtained;
1) It has been accepted that when blood glucose or glucose excess values were plotted semilogarithmically against time on a linear axis, a straight line relationship was obtained during IVGTT. This meant that the glucose disposal rate (k) had been considered to be constant regardless of time. But in 111 cases, when blood glucose excess values were plotted on the same manner as mentioned before, the slope of lines got steeper in course of time and in each time intervals k values were high enough. This means that the glucose disposal rate (k) in normal glucose tolerance is not a constant regardless of time, but gets larger and larger with time.
In 126 cases whose glucose tolerance revealed to be abnormal, the change in glucose disposal rate with time was very small.
From these results the glucose disposal rate should be regarded as a function of time and following equation should be used to diagnose glucose tolerance;
where X (t), X (0) is the blood glucose concentration at time t, pre-stimulated, respectively.
2) The dynamic property of glucose-induced insulin secretion was expressed as the transfer function of a proportional and derivative action to blood glucose concentration, and weighting function was calculated from the blood glucose concentration as an input and plasma insulin concentration as an output by the deconvolution method. This weighting function reflects the insulin secretion amount per unit of changing rate of glucose concentration in blood. It was clearly shown that the gain in the weighting function was small and the response was slow even in the individual whose glucose tolerance was slightly abnormal.
Furthermore, the time course of weighting function revealed that the larger the weightng function, the larger the change in glucose disposal rate with time, showing that glucose tolerance was controlled by the insulin secreted based on the change in glucose concentration in blood.
This method which permits quantitation of insulin response against unit of changing rate in blood glucose level is considered to be effective for the diagnosis of early stage and even before manifestation of diabetes mellitus, and also useful method for the follow-up study of diabetics.

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The relationships between serum triglyceride level (TG) and other metabolic derangements of 606 Japanese adults were examined with multiple regression analysis (stepwise forward selecting method) by computer system.
All of those 606 subjects were divided into three subgroups according to insulinogenic index (II) and to degree of glucose intolerance. The relationships between TG level and other metabolic derangements, such as basal insulin level (IRI), percentages to ideal body weight for scaling of obesity, and fasting blood sugar level (FBS) were examined in three subgroups as follows;(A) 98 subjects with lower-II (II<0.4) of normal glucose tolerance, (B) 196 subjects with hyper-II (II≥0.8) of normal glucose tolerance, and (C) 69 subjects with lower-II (II<0.4) of abnorma glucose tolerance.
In order to help explain the mechanism leading to the metabolic abnormalities of hyper-TG, hyper-IRI, and hyper-FBS, stepwise forward selecting regression analysis was carried out with computer, and its results suggested that the Mechanism of carbohydrate and lipid metabolism are quite different in above three groups. The subjects of group (A) have little possibilityof becoming hyper-FBS, but, those of (B) possibly become hyper-IRI and hyper-FBS when they become obese, and those of (C) were considered to be in insulin insensitivity because of hyper-IRI and hyper-FBS in spite of normal weight.
More striking findings were that the increase in fasting serum triglyceride level possibly could be a parameter of insulin insensitivity.

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Clinical investigation with diabetics was made whether biological potency and duration of action of highly-purified monocomponent (MC) Lente insulin are different from conventional insulin or not. Diurnal variation in blood sugar of 30 insulin-dependent diabetics was measured once a week by cross-over method and statistical consideration was made on the mean blood sugar level of both groups. As a result, no statistically significant difference was recognized as to the mean blood sugar level either in diurnal variation of both MC Lente and conventional Lente (p>0.05) or in M-value, a blood sugar control indicator advanced by Schlichtkrull and modified by Goto et al. The highest correlation of blood sugar level with M-value was seen at the time of peak blood sugar in a day (r=0.937), while that with fasting blood sugar level seen both at noon (r=0.864), at 16: 00 (r=0.795) and at 7: 00 (r=0.491) in said order. The result suggests that assessing diabetic control only with morning fasting blood sugar level may not always be dependable.

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Excess mortality from diabetes mellitus during epidemics of influenza was studied with the purpose of assessing the impact of influenza infection on diabetic patients.
Monthly mortality rates for the period 1961 to 1974 were taken from Monthly Report of Vital Statistics published by the Ministry of Health and Welfare, Japan. Expected mortality rates were obtained by the method of Serfling, i. e. from the regression equation, y=a+bt+csin (πt/6-θ), where coeffitients a, b and c were computed by the least square method. Relative intensity (excess mortality rate/standard deviation) was used as a measure of the statistical significance of excess mortality.
Large peaks of excess mortality due to respiratory diseases (pnuemonia, bronchitis and influenza) appeared during seven epidemic periods, defined by statistics based on reported cases of influenza. Mortality from diabetes mellitus increased significantly during three epidemics and nearly signif icantly during one epidemic out of seven epidemics of influenza. Fasting blood sugar levels were elevated in about 70% of diabetic patients during influenza-like illness in the winter of 1975-1976, at which time influenza A was prevalent.
Because of the increased risk of influenza associated death, the protection of patients from influenza is important in the management and control of diabetes.

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In a series of twenty-five children (0-14 years) born of diabetic mothers, the congenital abnormalities, the bone development, the neuropsychological development and the glucose tolerance were studied. The results are summarized as follows.
(1) Eighteen of the 25 children showed normal weight andheight of their age, 4 overweight with normal height, 2 normal weight with low height, and one underweight and low height.
(2) No congenital major abnormalities were observed, however minor ones were observed in eleven children (44%)
(3) Nineteen of twenty-two children showed normal development of the bones, and three delayed.
(4) None showed mental retardation.
(5) Fifteen of twenty-one children showed normal findings of EEGs, 4 borderline ones, and 2 abnormal ones.
(6) One-hundred gram-OGTT was examined in thirteen children. Eleven of them showed normal blood glucose patterns, and two borderline ones.
Four of them showed low insulin responses, one delayed response, 2 hyperresponses, and 6 normal responses.

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The procoagulant from human urine (urine factor, UF) was purified by the method of von Kaulla and Aoki. Subjects were divided into four groups. A: eight normal volunteers, B: eleven diabetics associated with arteriosclerotic complication, C: ten diabetics with diabetic microangiopathy and D: eight patients with secondary diabetes induced by adrenocortical hormone The mean level of UF in A, B, C and D were 3.51, 3.73, 1.62 and 4.05 mg/day respectively. The negative correlation between UF excretion and duration of diabetes mellitus was observed (r=-0.38, p<0.05). The correlation between UF excretion and creatinine clearance was also observed (r=0.419, p<0.05). The UF levels of some patients in group C decreased during warfarin treatment.
It is concluded that UF levels increased in the early stage of diabetes mellitus which seems to reflect the active intraglomerular coagulation, on the other hand it decreased in the later stage which seems to reflect the inactive state.

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Spontaneous hypoglycemia has been observed on rare occasions in renal failure. We observed episodes of spontaneous hypoglycemia in nondiabetic subject with renal failure.
A fourty-two-year old housewife was admitted because of dyspnea of sudden onset on Nov. 10, 1975. She had the history of acute glomerulonephritis and toxemia gravidarum. Her BUN was 137mg/dl, Na 137 mEq/L, K 5.5 mEq/L, Cl 105 mEq/L, creatinine 21.4mg/dl. s-GOT s-GPT and bilirubin levels were normal. s-cortisol, s-ACTH and h-GH levels were above normal. Thyroid function was normal. She undewent hemodialysis with gradual clinical improvement,
However early in the morning on Jan. 14, 1976 she developed severe hypoglycemia, less than 10mg/dl, with loss of consciousness and positive Babinski reflex of the left site, without hemiparesis. Intravenous glucose infusion resulted in gradual clearing of her mentsl ssatus and complete disappearance of abnormal neurological findings. The hypoglycemia was preceded three weeks by a transient rise of s-GOT (574 U), s-GPT (230 U) and al-P (32.6 K-AU) without icterus. However hepatic hypoglycemia was unlikely Hypoglycemia developed in the beginning and middle of February, and the beginning of April also. She died on April 20, 1976 because of heart failure. At autopsy, pancreatic adenoma could not be found, and liver cell glycogen centent was low in some part on PAS stain. The thyroid, the adrenal gland and the pancreas was morphologically normal.
Glucose tolerance test with fifty gram oral glucose revealed borderline blood sugar curve with maximal blood sugar level 156mg/dl at 120 minutes, and fair, delayed IRI response and paradoxical rise of h-GH. The IRI response was in the normal range during tolbutamide infusion, however blood sugar drop was only 8% at 20 minutes and blood sugar remained low even at 120 minutes. This might suggest some disturbances in recovery mechanism from hypoglycemia. Hypoglycemia developed fifteen hours after tolbutamide infusion. Blood sugar response to intravenous glucagon was poor; only 23mg/dl rise at 20 and 60 minutes. Glycogen deficiency in the liver cell must be the major cause of her hypoglycemia, whether it was resulted from renal failure itself or impaired caloric intake. Insulin tolerance test showed slightly prolonged half time disappearance of insulin (12 minutes) with slight blood sugar drop and rather high basal IRG. The first hypoglycemia on Jan, 14 did not seem to reflect increased insulin secretion, high insulin sensitivity or impaired caloric intake.
These results were essentially consistent with those of usual renal failure except for poor blood sugar response to glucagon. Probable glycogen deficiency in the liver cell might be the cause of hypoglycemia, and some disturbances in the recovery mechanism from hypoglycemia could be also. But these could not be adequate explanation for her hypoglycemia. Some unknown factor (s) in renal failure might be also responsible for hypoglycemia.

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Clinical evaluation was done in cases with transsphenoidal hypophysectomy by embedding radonseed for the treatment of proliferative diabetic retinopathy, comparing pre and post-operative states.
Four cases with severe proliferative type retinopathy associated with vascularization at peripapillary area as well as at the main vessels were analyzed. Following results were obtained; 1) Disappearance of vascularization was noted in three cases, to whom the surgery was performed in the early stage of development of vascularization. The cessation of the vascularization appeared at the 3rd post-operative month in the earliest, and no progression was seen even in these cases with the period of five years after the operation. In a patient in whom preexisting vascularization was found at the first examination, a slight reduction of vascularization was noted after operation, however, a severe bleeding into vitreous body was observed at the 10th month after the operation.
2) Out of three cases mentioned above, one showed no response of HGH following arginine administration. There was low degree response to FSH as well as LH in LH-RH test. The remaining two cases showed slightly inhibited response of HGH to arginine infusion, and one case demonstrated an inhibitory effect of the TSH reaction to TRH test. In all of these three cases, pituitaryadrenal function was proved to be normal. In one case in whom the progression of diabetic retinopathy was seen, the response of HGH after arginine load was prominently elevated preoperatively, which was slightly inhibited after the operation.
The effect of hypophysectomy seemed not to depend upon the grade of hypophysectomy. It was effective even in case with slight hormonal suppression.
There findings indicate that in the cases with new-vessel formed in the area around the opticdisc or front of the optic disc, disappearance of neovascularization would occur if followed by the surgery in the early stage. Based on these findings, hypophysectomy appears to be an effective method if it is done in the cases with proliferative retinopathy associated with vascularization.

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A case of insulinoma whose serum showed 125I-insulin binding presumably due to insulin autoantibody is reported. A 60-year old male was admitted because of morning disorientation and convulsion attacks, and was proven to have hypoglycemia and high serum insulin values at fasting. There was no history suggesting the injection of insulin in the past. Serum IRI values increased moderately after various stimulation tests. Binding of 125I-insulin to serum was demonstrated by polyethylene glycol method, gel filtration and hydrodynamic flow on a filter paper. This binding was inhibited by the addition of enough amount of unlabeled insulin. The precipitation experiments with anti-human immunoglobulin fractions suggested that insulin antibody is probably responsible;or this binding. Dilution test, recovery test and extraction of the serum suggested that the interference with IRI assay by this binding was negligible. By laparotomy, an adenoma, 1.3 cm in diameter was found in the tail of the pancreas. The tumor was rich in capillaries and contained a few scattered cells with the staining characteristics of B-cells by aldehyde-fuchsin and immunofluorescent methods. Electron microscopy revealed that most cells were agranular but a few cells contained secretory granules resembling those in normal B-cells. Insulin content of the tumor was2.6U/g and lower than that in the adjacent normal pancreas tissue (4.6U/g). Hypoglycemic symptoms and 125I-insulin binding of serum disappeared after the operation. The coexistence of insulinoma and “insulin autoantibody” such as found in this patient casts a new problem on the diagnosis of insulin autoimmune syndrome, although the causal relationships of the tumor and “antibody” remain unsolved.

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