Increase In Immunoreactive Insulin Research Articles

CHANGES IN CARBOHYDRATE METABOLISM IN PATIENTS WITH ALCOHOLIC CIRRHOSIS OF THE LIVER ASSOCIATED WITH NON-ALCOHOLIC FATTY LIVER DISEASE DEPENDING ON THE STAGE OF DECOMPENSATION


 
 
 The purpose of the research was to study the changes in adipocytokines in patients with alcoholic liver cirrhosis (ALC) associated with non- alcoholic fatty liver disease (NAFLD) depending on the stage of decompensation. A significant increase in immunoreactive insulin, the HOMA-IR index and a decrease in the QUICKI index in patients II gr. in comparison with patients I gr. has been detected, that indicating insulin resistance (p<0.05). On the basis of the results of the analysis of the correlation between the levels of leptin, adiponectin, resistin and carbohydrate metabolism, it was found that a stronger correlation was observed in patients suffering from ALC associated with NAFLD.
 
 

The relationship of plasma glucagon to the hyperglycaemia and hyperinsulinaemia of surgical operation

In a controlled metabolic study of 42 patients undergoing abdominal surgery a significant increase in basal values of immunoreactive glucagon (IRG) was found 24 hours postoperatively. No correlation between the onset and duration of hyperglycaemia and the increase of IRG was observed. No increase in immunoreactive insulin (IRI) was seen during operation, but there was a rise 24 hours postoperatively. The infusion of arginine was accompanied by a rise in IRG both pre-and postoperatively, but despite the high values obtained there was no accompanying further increase in basal plasma glucose in the postoperative situation. The pre- and postoperative IRI responses were similar. Our evidence suggests that glucagon is not a primary mediator of the stress response, or of the hyperglycaemia of surgical operation in these patients.

Transdermal iontophoretic delivery of insulin using a photoetched microdevice

In order to develop practical iontophoretic devices for insulin delivery, five types of device, a square type, a square anode with a U-shaped inset cathode-type device (2 divided type), and three types with a square anode, with, respectively, 4, 9 and 16 small square inset cathodes (4, 9 and 16 divided types), were fabricated by a photoetching technique, and their effectiveness was examined in vitro by measuring the permeability of 6-carboxyfluorescein (6-CF) through the excised abdominal skin of a nude mouse. All four divided types enhanced the penetration rate of 6-CF more than 16-fold compared with passive diffusion. To test the transdermal iontophoretic delivery of insulin in normoglycemic control and diabetic rats, we selected the 2 divided type device, since this pattern was the easiest to fabricate. A significant reduction in blood glucose level (BGL) of 33% after 90 min of treatment, and a corresponding increase in immunoreactive insulin (IRI) concentration were observed in diabetic rats during cathodic direct current (DC) iontophoresis (IP) at a constant voltage of 1.5 V. The effectiveness of pulsed IP was also studied, but there was no significant difference between DC and pulsed IP in the decrease of BGL. The level of current during the initial 10 min was closely related to the hypoglycemic effect. These findings suggest that some cathodic reaction products may change the function of the stratum corneum or that these products may develop a shunt pathway and enhance the transdermal delivery of aggregated insulin molecules. Iontophoresis-induced skin damage was also evaluated by measuring impedance changes. It was shown that at constant-voltage IP of 1.5 V, IP could be carried out for up to 60 min without any marked effects on the skin.

Topographic localisation of insulinogenic and insulinoprival areas in the hypothalamus.

Electrical stimulation of hypothalamic areas through stereotaxically implanted electrodes were carried out in conscious male rhesus monkeys. There was a significant increase in immunoreactive insulin (IRI) following laterla hypothalamus (LHA) stimulation. An opposite response was obtained from ventromedial hypothalamus (VMH). Thus, insulinogenic and insulinoprival responses were obtained from feeding and satiety, suggesting a significant role of insulin in the regulation of food intake.

Interaction of gastric inhibitory polypeptide, glucose, and arginine on insulin and glucagon secretion from the perfused rat pancreas.

Gastric inhibitory polypeptide (GIP) produced an increase in immunoreactive insulin (IRI) and immunoreactive glucagon (IRG) release from the isolated perfused rat pancreas. The magnitude of both effects was shown to be dependent on the prevailing glucose concentration. GIP stimulated IRG release at glucose concentrations less than 5.5 mM and IRI release at glucose levels greater than 5.5 mM. Arginine"stimulated IRG secretion in the presence of low glucose (2.7 mM) was potentiated by GIP. In contrast, GIP augmented arginine-stimulated insulin release only in the presence of arginine concentrations of (less than 20 mM, producing no further increase over a maximal arginine stimulus. The glucagonotropic effect of GIP in the presence of arginine was found to be suppressed by glucose, with the opposite effect observed with insulin release. It was concluded that the endocrine pancreatic action of GIP depends to a great degree on existing levels of modulating nutrients in the blood.

Studies on the metabolic effects of indapamide in the rat and mouse

SummaryIndapamide given acutely by mouth, in sub-threshold, threshold and maximal diuretic doses, did not modify plasma glucose in freely fed mice. Diazoxide, on the other hand, produced an intense dose-dependent hyperglycaemic response. In fasted mice, diazoxide, in a dose which produced little or no effect on plasma glucose, produced a marked augmentation of the hyperglycaemia produced by oral or intravenous glucose. In contrast, indapamide had no effect on the hyperglycaemia produced by orally or intravenously injected glucose, indicating a lack of effect on glucose tolerance. In anaesthetized rats, indapamide did not modify the hyperinsulinaemia produced by glucose infusion although this increase in immunoreactive insulin was completely prevented by diazoxide. The significance of these findings is discussed.

The insulinotropic action of gastric inhibitory polypeptide in the perfused isolated rat pancreas.

Gastric inhibitory polypeptide (GIP) produced a dose-related increase in immunoreactive insulin (IRI) from the perfused isolated rat pancreas. The doses employed were within physiological limits. This effect was glucose-concentration-dependent in that there existed a threshold concentration of glucose above which GIP exerted the insulinotropic action, and that, at a fixed concentration of GIP, increased glucose concentrations stimulated IRI release in more than an additive manner. A biologically active fragment of the GIP molecule was isolated and purified. All criteria have been satisfied that GIP is an insulinotropic hormone.

Oral administration of D-ribose in diabetes mellitus.

Thirty-four subjects were categorized on the basis of their glucose tolerance as normal (thirteen subjects), probable diabetics (six subjects), mild diabetics (five subjects), tolbutamide-responsive diabetics (five subjects) and insulin-dependent diabetics (five subjects). Fifteen grams of d-ribose dissolved in six ounces of water were administered orally to each of the subjects and the effect on serum glucose concentration was measured. The hypoglycemie effect of d-ribose varied in an orderly and progressive manner through the different categories of glucose intolerance. As their glucose intolerance increased in severity, the subjects were significantly less responsive to the blood glucose lowering effect of d-ribose. The serum immunoreactive insulin concentration in response to the oral administration of d-ribose was measured in the normal and mild diabetic subjects. The mild diabetics had a mean peak increase in immunoreactive insulin which was 2.6-fold greater than the normal subjects; however, the insulin concentrations attained were not significant in either group. Thus the insulinogenic response as determined in peripheral venous blood does not account for the differential hypoglycemie effect of d-ribose.

Effects of stimulation of the vagus nerve on insulin secretion.

Electrical stimulation of the peripheral cut end of the vagus nerve at cervical and diaphragmatic levels was performed to study its effects on plasma insulin concentrations in anesthetized dogs. Stimulation of the right and left cervical vagus and of the dorsal vagal trunk induced an immediate significant elevation in immunoreactive insulin concentrations in pancreatic effluent plasma, whereas stimulation of the ventral vagal trunk did not. A significant enhancement of immunoreactive insulin in femoral venous plasma was also seen in the first 3 groups, but the peak occurred somewhat later than in pancreatic venous plasma. The increases in immunoreactive insulin were not followed by decreases in blood sugar levels. (Endocrinology 80: 530, 1967)