Showing papers by "K. G. M. M. Alberti published in 1981"

Plasma Free Insulin Profiles After Administration of Insulin by Jet and Conventional Syringe Injection

Abstract: Plasma free insulin profiles in insulin-dependent diabetic subjects were compared after jet and syringe injection of insulin Jet injection of insulin resulted in a shift of the free insulin profile to the left Thus higher plasma free insulin levels were found over the first 30 min after injection (P less than 005), while after 240 min plasma free insulin levels were lower than those seen following syringe injection (P less than 005) Significant differences in the response of blood glucose and 3-hydroxybutyrate levels reflected the differences in plasma free insulin levels Jet administration results in more rapid absorption of insulin and could be useful in providing a more physiologic postprandial insulin profile than that seen after conventional injection

Simple filter paper method for home monitoring of blood glucose, lactate, and 3-hydroxybutyrate.

Abstract: Previous methods for assessing the control of diabetes at home have concentrated on the measurement of glucose concentrations in urine and, more recently, blood. These levels reflect only one aspec...

Dopaminergic control of ketogenesis in fasting

Abstract: SUMMARY The role of dopamine in starvation ketonaemia was investigated in male Wistar rats by administration of a specific dopamine receptor antagonist, metoclopramide (4 mg.kg−1.24h−1), or placebo, intragastrically during a 48-h fast. Starvation alone caused a fall in blood glucose and gluconeogenic precursor concentrations, which was unaffected by metoclopramide administration. Circulating 3-hydroxybutyrate and acetoacetate levels rose with fasting alone but metoclopramide impaired this ketonaemic response. After 48-h starvation, total ketone body concentrations (mean±SEM) were 2·28 ± 0·19 mmol/l with metoclopramide therapy, 3·49 ± 0·21 mmol/l with placebo, P < 0·001. Plasma non-esterified fatty acid levels were similar in metoclopramide- and placebo-treated animals, as were circulating concentrations of insulin, glucagon and growth hormone. Metoclopramide thus decreased the ketonaemic response to starvation without an apparent change in lipolysis or circulating hormone levels, suggesting a direct role for dopamine in production of starvation ketonaemia.

The gastro-entero-pancreatic hormone response to fasting in obesity

Abstract: A comparison of the metabolic and gastroentero-pancreatic hormonal responses of ten obese and eight lean subjects to 12 h and 36 h fasts has been made. Each subject was given a 50 g oral glucose tolerance test at the end of both 12 h and 36 h starvation. After the 12 h fast blood glucose and 3-hydroxybutyrate were similar in each group but blood glycerol was 30% higher in the obese subjects. Plasma insulin and vaso-active intestinal polypeptide were also higher in the obese subjects after 12 h starvation. After 36 h starvation in the lean subjects blood glucose was unchanged but on refeeding with 50 g oral glucose, glucose tolerance was impaired. In the same group blood glycerol and 3-hydroxybutyrate rose after 36 h starvation. Plasma glucagon, secretin and vaso-active intestinal polypeptide rose after 36 h starvation in the lean subjects but plasma insulin was unchanged. Refeeding with oral glucose suppressed the increased plasma glucagon, secretin and vaso-active intestinal polypeptide. After the 36 h fast in the obese subjects, blood glucose was unchanged, blood glycerol fell, but blood 3-hydroxybutyrate rose although to a reduced level in comparison with the lean subjects. In the obese group there was no change in plasma glucagon, secretin or vaso-active intestinal polypeptide after 36 h starvation, although plasma insulin fell. The results show different metabolic and gastro-entero-pancreatic hormonal responses to fasting in lean and obese human subjects and suggest an important metabolic role of glucagon, secretin and vaso-active intestinal polypeptide during starvation.

Differential Response to Infusions of Highly Purified and Conventional Bovine and Porcine Insulins

Abstract: The glucose clamp technique allows quantification of tissue sensitivity to insulin without modulation by the effects of hypoglycemia. The amount of glucose infused to maintain euglycemia during an insulin infusion gives a direct measure of tissue sensitivity. We have used this technique to compare the metabolic effects of highly purified porcine, highly purified bovine, and conventional insulins in diabetic subjects: (A) a group normally taking conventional bovine insulin, and (B) diabetics who had originally been treated with conventional bovine insulin and had changed to highly purified porcine insulin. Subjects were studied while attached to the Biostator with blood glucose values clamped at the basal level during a 2-h insulin infusion (0.01 U/kg/h). Both groups of diabetics received significantly more glucose in the first hour of the monocomponent porcine insulin infusion than during the same period either of conventional or of highly purified bovine insulin infusion. Highly purified porcine insulin infusion was also associated with a more rapid fall in blood ketone body concentrations. Highly purified porcine insulin infusion was accompanied by a greater and earlier increase in free insulin concentrations. All diabetics had antibodies to insulin but no differential antibody binding of beef and pork insulin was found in the two groups of patients. Thus, use of highly purified porcine insulin is associated with a more rapid onset of action and a greater initial increment in free insulin values.

Glucose controlled insulin infusion system (Biostator) application during surgery for a presumed pancreatic microinsulinoma.

Abstract: A glucose controlled insulin infusion system has been used during and after surgery for organic hyperinsulinism in a 37 year old woman. During surgery the system was used to monitor the blood glucose and, in order to avoid insulin hypersecretion, glucose was not infused. A strict correlation was observed between surgical procedures and metabolic behaviour, suggesting the resection of a microinsulinoma despite negative frozen section histology. After surgery plasma insulin was undetectable and an abnormal glycaemic level was observed during an IV glucose load. To ensure an adequate intake of fluid and calories 10% glucose was infused at a rate of 130 mg/min for 16h and blood glucose was clamped at 6.6 mmol/l by feedback insulin infusion. The gradual recovery of residual pancreatic tissue activity was demonstrated by the progressive decrease in exogenous insulin requirement, and confirmed by the normal glycaemic and insulinaemic response to an IV glucose load 20h after surgery.