[The effect of somatostatin on specific binding of insulin to receptors in patients with non-insulin dependent diabetes]. / Efekat somatostatina na specificno vezivanje insulina za receptore u obolelih od insulin nazavisnog dijabetesa.

Tests were performed of the effects of the Somatostatin (SMS) upon the concentration of Insulin, Glucagon and STH, as well as of the effects of SMS upon the specific binding of the insulin to the receptors. The tests were carried out on eight insulin-independent diabetics, and five healthy volunteers. The tests were made with placebo, followed by 100 ug of the analogue SMS 201-995, known under the name of Sandostatin. Blood specimens for determining all parameters mentioned above were taken at 9 a.m., 3 p.m., 9 p.m., and 3 a.m. (09 h, 15 h, 21, and 03 h). The goal of the tests was to determine whether the SMS had any effect upon the glucoregulation, and at which level changes take place. In the group of healthy volunteers, a considerable decrease of insulin took place six hours after the administration of STH, and the decrease of the glucagon was especially marked, tending to increase again after six hours, while the specific binding of the insulin to the receptors, and the number of receptors were decreased six hours following the administration of the SMS when compared with the placebo, and without tending to reach the previous levels until 3 a.m. (03 h). In insulin-independent diabetics, the SMS leads to a considerable drop of concentrations of Insulin, Glucagon, STH and to a specific binding of the insulin.(ABSTRACT TRUNCATED AT 250 WORDS)

[The occurrence of diabetes and organization of diabetes health services in Yugoslavia]. / Ucesce dijabetesa i organizacija antidijabetesne sluzbe u Jugoslaviji.

According of data of the antidiabetic medical service, in Yugoslavia there are registered 380,000 patients with diabetes. This makes 1.70% of total population. In northern parts of the country, with a higher development of agriculture, industrialization and urbanisation, the prevalence of diabetes is over 2%. In southern parts, mostly highlands, the prevalence of diabetes is less than 1%. According to needs, the antidiabetic medical service is better in developed parts of the country with higher prevalence of diabetes. Altogether in Yugoslavia, there are 8 central institutions for diabetes and endocrinology, 81 dispensaries, and 130 out-patients units for diabetics. The antidiabetic medical service is in progress, qualitatively and quantitatively, along with the progress of the prevalence and incidence of diabetes.

[Determinants of susceptibility to the induction of autoimmune diabetes in inbred strains of rats]. / Ispitivanje determinanti ostljivosti na indukciju autoimunog dijabetesa u cistih sojeva pacova.

Interleukin 2 (IL 2) proved to be important for the generation of autoreactive T cells in the pathogenesis of different autoimmune disorders, including diabetes. Also, we have previously shown that lymphoid cells obtained from inbred strains of rats Dark August (DA) and Albino Oxford (AO) exhibited a genetically determined difference in their ability to produce IL 2. In this study, in DA and AO rats, we analysed the susceptibility to the induction of autoimmune diabetes with multiple subdiabetogenic doses of alloxan. Rats were injected i.v. with 25 mg/kg b.w. of alloxan in 5 consecutive days. All DA rats developed moderate and persistent hyperglycaemia 15 days after the induction. In contrast, AO rats failed to develop the disease after the same regimen of induction. When the induction was made in (AO x DA)F1 rats, all of them developed the disease similar to the susceptible parental DA strain. However, the onset was delayed (the 40th day after the induction) and the glycaemia was constantly lower than in DA rats. Our results indicate that the difference in the response to the induction of autoimmune diabetes between susceptible DA strain, being high IL 2 producer, and resistant AO strain, being low IL 2 producer, is genetically determined. The results also suggest that this control could involve the gene determining the level of IL 2 production in DA and AO rats, thus signifying that the susceptibility to the induction of this form of autoimmune diabetes could be related to the level of IL 2 activity.

Postprandial response of serum cationic trypsin-like immunoreactivity in insulin-dependent diabetes mellitus.

Conflicting reports exist on the postprandial response of serum cationic trypsin like immunoreactivity (SCTLI). The purpose of the current study was to examine the postprandial response of SCTLI in healthy persons and in insulin dependent diabetes mellitus (IDDM) patients and relate this to C-peptide secretion. The study was performed on six healthy males 25-40 years old and in nine male IDDM patients 25-38 years old. To all the patients after an overnight fast was given a standardized breakfast. Blood samples were obtained through a butterfly needle inserted into the antecubital vein at 0, 30, 60 and 120 minutes. Radioimmunoassays were performed using commercially available kits: for SCTLI CIS-SORIN and for C-peptide BIODATA. In healthy persons there was a significant rise of SCTLI concentration at 30 minutes, and C-peptide at 30 and 60 minutes. IDDM patients showed lower basal levels of SCTLI and C-peptide, without any significant changes of SCTLI and C-peptide during the test. We concluded that trypsin appearance in serum closely correlates with endocrine pancreatic function.

Detection of compounds in serum inhibiting insulin binding to erythrocyte receptors.

The erythrocytes were used as a model system to study insulin receptors in diabetic patients with highly increased insulin resistance. The specific binding of 125I-insulin to erythrocytes of these patients was markedly reduced. When erythrocytes prepared from non-diabetic subjects were exposed to serum of these patients, the decrease of insulin binding was reproduced. The binding of insulin showed a displacement curve that is parallel to the control values over the same range of hormone concentration, even in the case when control erythrocytes were preincubated with serum of diabetics with increased insulin resistance. These results indicate the presence of certain component in blood plasma of examined patients which alters insulin binding to receptors. The developed assay provides an efficient method for detection and identification of substances presented in the serum which can influence the binding of insulin to the specific sites as well as its biological effects.