The importance of the matrix has been widely recognized in the maintenance and expression of cellspecific functions in culture. In the previous study, we reported that cellular attachment to culture dishes could be controlled by coating the dishes with a polyelectrolyte complex (PEC), which was prepared by mixing equimolar polyanion with polycation. In the present study, we employed four PECs, PVBMA-PAA, PVBMA-COA, PVBMA-CLA and PVBMA-CSA, each with a different hydrophilic-lipophilic balance. PVBMA-PAA is the most lipophilic of the four PECs. Their hydrophilic property increases in the order given. Culture dishes were coated with PECs and their effects on the growth and insulin secretory capacity of RINr cells was investigated. RINr cells were inoculated into PEC-coated or non-coated dishes and cultured for seven days. The cells grew as monolayers in non-coated dishes, while cell aggregates of various sizes were formed according to the hydrophilic-lipophilic balance of the PECs. Large, freefloating aggregates were formed on PVBMA-PAA coated dishes, whereas cell sheets with small aggregates grew on PVBMA-CSA coated dishes. Growth of cells was retarded on PVBMA-PAA and PVBMA-COA coated dishes. The amounts of secreted and intracellular insulin in the PEC-coated groups increased significantly on a per cell basis in comparison with the non-coated control groups.
The application of PECs to culture dishes is of value in regulating the morphology and function of RINr cells in vitro.

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The present paper reports the culture of human microvascular endothelial cells under improved culture conditions. The cells were isolated from omental tissue obtained at abdominal surgery by Kern's method and were cultured in non-coated tissue culture dishes in either TC199 or MCDB131 medium supplemented with fetal bovine serum.
The cultured cells were identified as endothelial cells by immunofluorescence for Factor 1M-related antigen and by the ability to take up a acetylated LDL and to produce prostacyclin. Since the production of prostacyclin decreases with the number of transfers, it is desirable to use the cells from the second to the fourth transfer generations for the experiments. The cells were found to have the insulin receptor, and the number of receptors was calculated to be 10⁴ per cell. Growth and maintenance of the cells were better in the cells cultured with MCDB131 medium than with TCM199. This culture system provides a large number of pure human microvascular endothelial cells and is of great value for studying the pathogenesis of diabetic microangiopathy.

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In the present study, epinephrine (Epi)-and collagen (Col)-induced platelet aggregation and alpha-granule release reations in vitro in the presence or absence of three antiaggregatory agents, taurine (a native sulfur amion acid), OKY-046 (a thromboxane A2 sythetase inhibitor) and W-7 (1 Ca²⁺-calmodulin antagonist) in 48 non-insulin-dependent diabetics were compared with the results of these reactions in 30 normal controls. Oneμg/ml Epi-induced aggregation rates and beta-thromboglobulin (β-TG) release in diabetics were significantly higher than in the controls. Taurine (50mM), OKY-046 (2.5mM) and W-7 (50μM) significantly suppressed both reactions induced by Epi and Col in both controls and diabetics. However, the degree of suppression of the two reactions by the inhibitors in diabetics was weaker than in the controls. In the diabetic group, HbA₁ levels were significantly correlated with Epi-induced platelet aggregation rates in the presence of OKY-046. In 10 diabetics, Epi-and Col-induced reactions tended to be suppressed during one-month glycemic control with only diet therapy. These results indicated that platelets from diabetics may hyperfunction with respect to aggregation and the alpha-granule release reaction in vitro, in which thromboxane A₂, the Ca²+-calmodulin system and other factors might be involved, and that those disorders may be related to relatively long-term glycemic control.

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Effects of subcutaneously infused insulin on the kinetics of VLDL-triglyceride were compared with those of intraperitoneally infused insulin in sera of rats fed sucrose. The subcutaneous route delivered insulin primarily peripherally, i. e., extrahepatically whereas the intraperitoneal route delivered insulin intraportally, i. e., hepatically. Compared with intraperitoneally delivered insulin, subcutaneously delivered insulin was associated with higher peripheral insulin, lower serum glucose, lower serum FFA, lower serum triglyceride, higher adipose tissue lipoprotein lipase activity, similary increased portal insulin and similarly increased rates of triglyceride secretion. Compared with rats fed sucrose but receiving no exogenous insulin, sucrose-fed rats receiving intraperitoneal insulin had a significant decrease in serum FFA, minimal increases in peripheral insulin and adipose tissue lipoprotein lipase activity, no change in serum triglyceride or glucose, and a significant increase in rates of triglyceride secretion. These results indicate that subcutaneously delivered insulin stimulates triglyceride removal more than triglyceride secretion, and that intraperitoneally infused insulin stimulates removal and secretion of triglyceride equally. The different routes of insulin delivery can produce different insulin effects in hepatic and extrahepatic tissues which, in turn, are followed by alterations in the balance between triglyceride secretion into the circulation and triglyceride removal from the circulation. Exogenous insulin, regardless of the route of administration, produced no significant changes in plasma concentrations of glucagon, epinephrine, norepinephrine and dopamine, indicating that counter-regulatory hormones are not responsible for an increased rate of triglyceride secretion associated with exogenous hyperinsulinemia.

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Two diabetic patients with gas-producing non-clostridial infections are reported below.
Case 1, a 73-year-old woman, who had suffered from poorly controlled diabetes for 8 years, was admitted because of cholelithiasis. After admission, infection was diagnosed in the area of the lower back. Two months later, subcutaneous emphysema was observed in the same site. The abscess, with its subcutaneous gas production, was cured by surgical drainage, debridment, antibiotics, control of plasma glucose with insulin, and improved nutrition.
Case 2, a 45-year-old man, who had had decompensated liver cirrhosis and diabetes mellitis treated with an oral hypoglycemic drug, was admitted because of swelling and pain in the left hip. The day after admission, massive subcutaneous gas production was found in the hip and thigh, and he fell into septic shock with disseminated intravascular coagulation. Despite prompt surgical drainage and intensive medical care, he died the same day.
The 73 cases reported in the Japanese literature, including our 2 cases, were reviewed to elucidate the differences between the 34 fatal and 38 non-fatal (1 unknown) cases, and the results were as follows:
1) Plasma glucose was poorly controlled in most cases in both groups.
2) A short incubation period and poor nutritional parameters appeared to indicate poor prognosis.
3) All six diabetic cases complicated by liver cirrhosis were fatal.
4) Control of plasma glucose, sufficient surgical treatment, and improved nutrition were considered to be important for the treatment of diabetic cases with gas-producing non-clostridial infection.

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An 84-year-old woman underwent an operation for an inguinal incarcerated hernia. After the operation she had heart failure and paroxysmal atrial tachycardia and was administered 300 mg of disopyramide per day for eight months. She had syncopal attacks three times during that period. At each attack the ECG showed no marked change, but the plasma glucose levels were 29, 25 and 29 mg/dl, respectively. She recovered immediately from each attack after intravenous injection of glucose.
After cessation disopyramide administration, hypoglycemic attacks did not occur during the observation period of several years. The values of IRI and IRG at the third attack were 46.2 μU/ml and lower than 20pg/ml, respectively. After 72-hr fasting with administration of disopyramide the plasma glucose and serum IRI were 52 mg/dl and 41 μU/ml, respectively, but a hypoglycemic attack was not induced. Euglycemic glucose clamping showed decreased tissue sensitivity to insulin after oral administration of 300 mg of disopyramide. These results suggest that the mechanism of disopyramide-induced hypoglycemia has some relation to the increased serum level of IRI and the decreased serum level of IRG, but there is no evidence that disopyramide increased tissue sensitivity to insulin.

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Hyper-HDL-(α)-cholesterolemia was observed in a 34-year-old female diabetic patient. Her diabetes mellitus was diagnosed in 1986. She was treated initially with an oral hypoglycemic agent. Insulin treatment was started in 1987. However, diabetic control was not satisfactory and she was admitted to Kanazawa Medical University Hospital in 1988. Her HbA_1c and serum fructosamine were 11.4% and 6.5 mmol/l, respectively. She had no obvious diabetic complications. Plasma concentrations of cholesterol and triglyceride were 216 and 71 mg/d/, respectively, while HDL-cholesterol (111 mg/d/) was extremely high. Cholesterol concentrations in HDL-subfractions fractionated by ultracentrifugation showed and increase in HDL2. Lipid concentrations as VLDL, IDL and LDL were within normal ranges. The plasma level of apo A-I (163.1 mg/dl), a major apolipoprotein in HDL, was increased. LCAT activity was normal. The cholesterol ester transferase activity (CETA) was decreased to 18.9% compared with normal controls (31.2±4.0%). De creased CETA may be responsible in part for hyper-HDL-(α)-cholesterolemia in the present patient.

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The effect of long-term administration of 15-deoxyspergualin (DSG) on glucose tolerance was investigated in mice.
DSG (6 mg/kg body weight/day) was given intraperitoneally in thirteen ICR adult mice for six months. The control group (n=12) was given saline only. Pancreatic endocrine function was determined by intraperitoneal glucose tolerance test (IP-GTT, 1 g/kg body weight) before and after DSG treatment. Body weights (g) after administrations were not significantly different between the DSG-and saline-injected groups (33.5±0.7 and 35.4±1.2, respectively). Plasma glucose levels in IP-GT (mg/dl) after six month's administration of DSG (0 min: 106±9, 30 min: 163±9, 60 min: 195±12) were not significantly different from those before DSG injections (97±6, 182±13, 185±15), and those in saline-injected mice (96±7, 164±9, 165±10). Immunohistochemical investigation revealed no remarkable changes in insulin-containing B cells between the DSG-and saline-injected groups.
These results suggest that the long-term administration of DSG may not have any adverse effects on glucose tolerance and may be useful as an immunosuppressant for pancreatic transplantation.

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To study possible Ca²⁺ overload into cardiac muscle, we measured the voltage-sensitive Ca²⁺ channel in cardiac muscle membrane fraction isolated from control and 10-wk-streptozocin-induced diabetic rats using [³H] PN 200-110, a dihydropyridine derivative, as a ligand. The maximum binding sites of [³H] PN 200-110 in cardiac membrane isolated from diabetic rats increased 61%(P<0.01) above that of the control without a significant change in Kd. Furthermore, [3H] PN 200-110 binding to control cardiac membrane was dose-dependently inhibited by verapamil, a phenylalkylamine Ca²⁺ antagonist, but such was not the case in cardiac membrane isolated from diabetic rats.
These results indicate both quantitative and qualitative changes in the voltage-sensitive Ca²⁺ channel and suggest another new mechanism for possible Ca²⁺ overload in the diabetic rat heart.

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NIDDM is a disease with decreased meal-related insulin secretion but with possible near-normal basal insulin. Therefore, the substitution of prandial insulin by injections of regular insulin was tested in NIDDM with secondary failure on sulfonylureas.
Fifteen consecutive nonobese NIDDM patients participated in the study. All had been admitted to hospitals because of poor glycemic control due to secondary failure with long-term sulfonylurea treatment (age: 52.1+10.4 years (M + SD), estimated duration of DM: 15.2+ 7.5 years, duration of sulfonylureas administration: 7.0+2.2 years).
Patients were given regular insulin 30 min preprandially for 3 meals. Insulin injections were begun at doses of 10U, 8U and 6U for breakfast, lunch and dinner, respectively. Then, according to the daily profile of plasma glucose taken every 3-4 days, doses were adjusted to obtain normal pre-and 2-h postprandial glycemias.
At 4 weeks after the initiation of insulin treatment, in 13 out of 15 patients (51.5±10.9 kg) perfect normalization of both meal-related and pre-breakfast glycemias was established with insulin doses of 10.5±2.6U, 8.8±2.4U and 7.1±2.7U, for breakfast, lunch, and dinner, respectively. Only 2 patients required additional bedtime long-acting insulin to obtain pre-breakfast normoglycemia. There was no significant difference in urinary C-peptide excretion rate from 11 pm to 7 am between the 13 responders and the 2 others.
It was demonstrated that in nonobese NIDDM with secondary failure on sulfonylureas, 3 injections of sufficient regular insulin before each meal could control glycemia throughout the day.

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