Tolbutamide has been shown to be an uncoupler of oxidative phosphorylation of liver mitochondria. Previous reports demonstrated that its uncoupling action was greatly accelerated by Ca²⁺ and partially restored by EGTA. The present authors investigated the accelerating effect of Ca²⁺ on the uncoupling action of tolbutamide more precisely, using rat liver mitochondria. The following results were obtained.
(1) The uncoupling action of tolbutamide was accelerated with increase in concentration of Ca²⁺ in the range of 0.1-0.4 mM.
(2) Five mM or 10 mM carnitine, in proportion to its concentration, accelerated the action of tolbutamide.
(3) Decrease in the substrate concentration from 10 mM to 1 mM resulted in an acceleration of the action of tolbutamide.
(4) Under conditions which accelerated the action of tolbutamide, the presence of 10 mM carnitine and 1 mM substrate, further addition of 50μM Ca²⁺ resulted in a strong acceleration of the action of tolbutamide: only 1 mg% tolbutamide caused significant uncoupling and 10 mg% tolbutamide caused complete uncoupling.
(5) Seven mg% tolbutamide demonstrated complete uncoupling in the presence of 50μM Ca²⁺ and 1 mM substrate using aged mitochondria.
The above findings suggest that Ca²⁺ has an intimate relation to the uncouplig action of tolbutamide. Previous results showing that tolbutamide changed the permeability of Ca²⁺ through the mitochondrial membrane seem to be in good accord with the present study.

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Several hypothetical mechanisms (i.e. insufficiency of glucagon secretion, malabsorption due to pancreatic insufficiency, and an inhibitory effect of ethanol on glycogenesis of the liver in patients with alcoholic pancreatitis) have been postulated to account for the proneness to develop severe, sometimes fatal, hypoglycemic attacks in patients with pancreatic diabetes. However, the possible changes in secretory profiles of anti-insulinogenic hormones associated with such a hypoglycemic state in patients with pancreatic diabetes, have not yet been investigated insofar as we are aware.
In order to gain some insight into this intriguing problem, we examined the responses of glucagon, cortisol, growth hormone, TSH, T₃, T₄ and C-peptide to insulin-induced hypoglycemia (MC-actrapid insulin, O.1U/kg, iv) in 5 control subjects, 4 patients with IDDM and 9 patients with calcifying pancreatitis complicated by pancreatic diabetes.
The recovery of the plasma glucose following insulin-induced hypoglycemia was slower in the diabetics compared to the controls, and the nadir of blood glucose was also reached later in the diabetics (C: 30 min 20±3.5mg/dl, DM: 45min 42±5, and CP: 45min 28±2.2). The plasma glucagon began to rise 30 min after insulin administration and reached a peak value at 45 min in both the control and IDDM groups (262±20pg/ml, and 177±34, respectively), whereas that in the patients with pancreatic diabetes was significantly lower than that in controls in terms of the peak. Although the peak levels of plasma cortisol in the patients with pancreatic diabetes were obtained at 60 min after insulin administration as in controls, significantly lower responses were observed at each of 15, 30 and 45 min in this group compared to the controls. In view of the substantial increments of glucagon and cortisol produced by insulin-induced hypoglycemia, which were calculated by subtracting the basal value from each one obtained thereafter, bothΣΔglucagonand ΣΔ cortisol in the patients with pancreatic diabetes were signihcantly smaller than those in the controls (P<0.01) and IDDM patients (P<0.05). Although the peak plasma GH value in the 2 groups of patients was apparently lower than that in the controls, no statistically significant difference was observed among them possibly due to the widely varying values obtained in the controls. The plasma level of C-peptide after insulin administration decreased significantly from the basal value in controls, but no significant change was noted in the 2 groups of patients. There were no observed changes of thyroid hormones with the insulin loading test in any of the present groups.
The above results suggest that the relative proneness to develop severe hypoglycemic attacks in patients with chronic pancreatitis under insulin therapy may be explained, at least in part, by combined secretory insufficiency of glucagon and cortisol.

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The fasting serum elastase I concentrations in 74 normal subjects and 183 diabetics, 107 of which had various other diseases, were determined by radioimmunoassay using double antibody methods (DAINABOT).
The following results were obtained.
1) The mean serum immunoreactive elastase I (=IRE₁) level in 74 normal subjects was 233.5±65.7ng/dl. The serumIRE1 levels tended to be higher with increasingage. Subjects in their fifties had significantly higher levels than subjects in their twenties (p<0.05).
2) The serumIRE1 levels in IDDM were 142.2±24.0ng/dl. These levels were lower than those in the patients with other diseases.
3) The fasting serum glucose concentrations were not correlated with the serumIRE1 levels. On the other hand, as theHbA₁ concentrations became higher, so the serumIRE1 levels became lower (p<0.001).
4) The serumIRE₁ levels were not related to diabetic duration, therapy or diabetic retinopathy.
5) The highest serumIRE1 levels were in patents with acute pancreatics (1175.7±26.0ng/dl) and renalinsufficiency (446±108.0ng/dl).

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Since one of the major aims in the treatment of pregnant diabetics is the delivery of normal newborns, we investigated how pregnant diabetics could gain weight in a manner with enabled them to deliver normal infants.
The subjects comprised 52 pregnant diabetics (62 deliveries) whodelivered after 38 weeks of gestation. Almost all subjects received insulin therapy.
The women were mainly given a diet proposed by committee membersof the nutritional department of the Welfare Ministry in 1975. Maternal weight gainwas defined as the maximum weight difference between prepregnancy and predelivery.The maternal weight gain was found to be 3.5 to 15 kg (mean, 8.2±2.7 kg), which correlated posmaxmatsuctheitively with the birth weights of the newborns (p<0.05).This gain was not correlated with the imum insulin dosage or control of blood glucose during pregnancy. We estimated the adequate ernal weight gain to be 6 to 8 kg, since the birth weight of newborns (mean 3188±502 g) in h women was almost the same as the birth weights of normal newborns, and complications in newborns were minimal.
It is concluded therefore that diet therapy which prevents excess maternal weight gain is an important factor in the delivery of normal newborns in diabetic women.

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We previously reported that an increase of column chromatographically measured hemoglobin AI (HbAI) levels in chronic renal failure (CRF) was caused by an increase of the cyanate-hemoglobin adducts (carbamylated hemoglobin). In the present study, we investigated the effects of CRF on Hb Ai levels measured by a spectrophotometric method using phytic acid. Phytic acid, one of the 2, 3-DPG analogs, is known to bind to hemoglobin at its 2, 3-DPG pocket, and therefore the binding of phytic acid on glycosylated hemoglobin is sterically inhibited.
Hb Ai levels were measured in 20 CRF patients without diabetes, whose serum creatinine levels were above 1.5mg/dl. The HbAi values were correlated significantly with BUN (r=0.68, p<0.001, Y=0.04X+4.37, X=BUNmg/dl, Y=-Hb AI%), but did not with FBS (r=0.30, N. S.).
Red blood cells, drawn from a normal subject, were incubated for 3 days in media containing 100, 500 and 1000 mg/dl of urea N, and the HbAI levels were determined by the phytic acid-spectrophotometric method. The concentrations of cyanate, which is in equilibrium with urea in aqueous solution, were 1.25, 3.44 and 7.25 mg/dl, respectively. The Hb Ai levels were elevated with increasing concentrations of cyanate, and the HbAI levels in each medium were 5.7±1.0, 33.7±2.8 and 55.8±3.8%(M±SD, N=4), respectively.
These results suggest that the increase of HbAi levels measured by the phytic acid-spectrophotometric method in CRF can be attributed to an increase of carbamylation, but not glycosylation of hemoglobin, and that cyanate binds to hemoglobin at its 2, 3-DPG pocket.

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Serum concentrations of thyroxine (T₄), triiodothyronine (T₃), reverse triiodothyronine (rT₃), free thyroxine (FT₄), thyroxine-binding globulin (TBG) and thyroid stimulating hormone (TSH) were measured in 50 patients with uncontrolled diabetes mellitus.
In 2 patients, both the T₃ and T₄ levels were below the normal range, and one of them proved to be primary hypothyroidism due to a low free thyroxine level and high concentration of thyroid stimulating hormone. The other patient showed normal levels of FT₄ and TSH but a low TBG concentration.
The remaining 48 cases revealed a normal T₄ concentration, and 17 of them had a subnormal concentration of T₃, so being referred to low T₃ syndrome.
The concentrations of T₄ and TBG were significantly lower in the patients with low T₃ syndrome than in those with a normal concentration of T₃. The concentration of rT₃ was also lower, but not significantly in the patients with low T₃ syndrome than in those with a normal level of T₃. The concentrations of FT₄ and TSH were normal and not different between the groups.
The above data suggest that low T₃ syndrome in uncontrolled diabetes mellitus is due to a decrease of TBG concentration. The levels of fasting blood sugar was higher in the patients with low T₃ syndrome and they were less obese than those with a normal T₃ concentration.
The frequency of complicaing nephropathy or liver cirrhosis was similar in both groups. The decrease of TBG concentration in the patients with low T₃ syndrome could not therefore be attributed to excretion as urinary protein or to impaired synthesis in the liver.

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Increasing numbers of diabetics with coronary atherosclerosis have undergone coronary artery operations. Clinical use of an extracorporeal circulation with moderate hypothermia in cardiac operations has been reported to lead to severe hyperglycemia, even in healthy subjects.Blood glucose regulation is not easy under such special conditions.
We studied the glucose disappearance rate, insulin secretion in response to iv glucose load, and the effect of exogenously given insulin on glucose disappearance during cardiac operations. The following series of experiments were performed in9 non-diabetics:
1) An intravenous glucose (22.5g) tolerance test (iv GTT) before the operation,
2) An intravenous tolerance test with glucose and8units of Actrapid Insulin (I.8-iv GTT) before the operation,
3) An intravenous tolerance test with glucose and16units of Actrapid Insulin (I.16-iv GTT) during the operation.
The glucose disappearance rates (K-values, %/min) were calculated according to Hamilton et al.
The mean (±SD) K-value at iv GTT before the operation was2.21±0.45 (n=4).However, it became0.15±0.66 (n=4), and no insulin secretion in response to hyperglycemia was observed during the cardiac operation.Even when the serum insulin levels were increased more than500μU/ml by I.16-iv GTT during the operation, the K-value was not significantly increased in5patients (1.10±0.88), compared to that of I. 8-iv GTT (3.10±0.69).
As a control, in 4 patients who underwent gastrectomy, the same kinds of tests were performed. It was found that a significant increase in K-value was observed by iv GTT with 8U of Actrapid Insulin during the operation.
These data suggest that both glucose disposal and insulin secretion were extremely impaired during cardiac operation using an extracorporeal circulation with moderate hypothermia.Also, a high level of insulin added exogenously failed to improve the glucose disappearance rate in such a condition.

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It has been postulated that long-term physical training can improve glucose tolerance and insulin sensitivity. The aim of the present study was to estimate the training effects quantitatively. Tissue sensitivity to insulin was evaluated in 5 trained athletes and 6 untrained controls. Insulin sensitivity was determined by the euglycemic insulin clamp technique (insulin infusion plus a variable glucose infusion). The amount of glucose infused is a measure of the overall tissue sensitivity to insulin.
During the insulin clamp study, comparable plasma glucose (80-90 mg/dl) and insulin (70-100μU/ml) were achieved in both groups. However, the glucose infusion rate in the athletes (10.12±0.38 mg/kg/min) was significantly higher than that in the controls (7.20±0.34 mg/kg/min)(p<0.001). During the euglycemic insulin clamp, FFA decreased rapidly by approximately 80% in both groups, while glycerol decreased gradually in both groups and showed only a 20% reduction over a 120-min period. The urinary catecholamine concentrations in the athletes were similar to those in the controls. Also, these levels did not change during the insulin clamp.
Based on these results, it can be concluded that tissue sensitivity to exogenous insulin is about 40 % higher in trained athletes, and physical training can reduce the insulin requirements in insulin-dependent diabetic patients in addition to being beneficial to non-insulin-dependent diabetic patients.

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We analyzed data for a 7-year study on home blood glucose monitoring, and clarified the limitations of the effectiveness of home monitoring.The subjects cmprised 63 diabetics (IDDM 38, NIDDM 25) who began home monitoring with a meter (n=46) or visual inspection (n=17) from 1976 to 1981.The protocol for home monitoring was as follows: 1) fasting blood glucose: daily, 2) diurnal profile: twice per month, and 3) spot checks at hypoglycemic attacks, etc.HbA, determinations were performed monthly at the hospital visit and used as an indicator of glycemic control.
The glycemic control of the 63 patients in terms of HbAi was excellent in 5 (13%) of the 38 IDDM cases and 13 (52%) of the 25 NIDDM cases, with a value of less than 9%.After beginning home monitoring, the yearly average HbAi improved significantly from 12.4±2.0% to 10.5±2.2% in IDDM and 10.1±1.8 to 8.4±1.6% in NIDDM (p<0.01).The HbA, level reached the lowest within a year of the start of home monitoring and remained at a similar level thereafter. In diabetic pregnancies, statisfactory values were obtained at 8.2±0.7% in IDDM and 7.4±0.7% in NIDDM.The improvement was observed regardless of the device used.As for the insulin regimen, the type, timing and/or mixture of insulin rather than the total dose were altered.100% of IDDM and 74% of NIDDM undertook multiple insulin injection after home monitoring.
The results revealed that home monitoring of blood glucose can be highly effective both in IDDM and NIDDM.However, the data were still unsatisfactory since our target was to achieve normalization of the blood glucose.To overcome the limitations, a tailor-made insulin regimen, the patient's strict adherence to diet control, and patient education which involves measures to alleviate the psychological burden may be vital.

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The first case of hypoglycemia caused by adenocarcinoma of the gallbladder is reported. An 82 year-old woman was admitted in July 1980, with a history of recurrent hypoglycemic attacks for one year.
The blood glucose levels and plasma insulin levels during the hypoglycemia were less than 40 mg/dl and less than 5 μU/ml, respectively. The insulin responses during the tolbutamide test etc. were very low. Serum human growth hormone responsed little to glucagon-propranolol load, but responsed well to reattack of hypoglycemia. No other endocrine insufficiencies were recognized. Insulinlike activity as estimated by ¹⁴C-glucose oxidation using epididymal fat pad was 1, 050 μU/ml (normal control serum level, less tlan 57 μU/ml). Liver scintigraphy revealed a small defect, which was recognized as a small hypervascular nodule at the distal portion of the cystic artery branches by celiac angiography. At operation, the tumor was located on the base of the gallbladder with two small metastatic nodules in the normal liver. A specimen of this tumor revealed well-differentiated adenocarcinoma of the bile duct type with abundant fibrotic stroma. The electron microscopic findings showed secretory granules in the tumor cells. The hypoglycemic attacks subsided completely after removal of the tumor. The amount of resected tumor was estimated to be about 150 g, and was too small to consume the 200 g/day of glucose which was needed to prevent hypoglycemia of this patient.
All these findings support the view that this patient's hypoglycemia was caused by insulinlike activity originating from the adenocarcinoma of the gallbladder.

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Insulin binding was studied using erythrocytes obtained from two homozygotes of familial partial deficiency of plasma lecithin: cholesterol acyltransferase (LCAT). Both patients revealed corneal opacity, plasma LCAT activity with 14-15% of the normal value, target cells and abnormalities of plasma lipoprotein composition with a reduced ester ratio of cholesterol. In addition, abnormalities of lipid composition of red cell ghosts were observed: cells obtained from both patient showed increased amounts of cholesterol and lecithin and an increase in the lecithin/sphingomyelin ratio.
Insulin binding to the red cells was also increased, mainly due to an increase in binding affinity without a significant change in receptor number. Further studies are needed to confirm whether the increase in binding affinity is due to the change in lipid composition of the red cell membrane.

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