The incretin effect, which is a unique stimulus of insulin secretion in response to oral ingestion of nutrients, is calculated by the difference in insulin secretory responses from an oral glucose tolerance test (OGTT) and a corresponding isoglycemic intravenous glucose infusion (IIGI) study. The OGTT model of this study, which is individualized by fitting the glucose profiles during an OGTT, w...

Bed rest and physical inactivity are the consequences of hospital admission for many patients. Physical inactivity induces changes in glucose metabolism, but its effect on the incretin effect, which is reduced in, e.g., Type 2 diabetes, is unknown. To investigate how 8 days of strict bed rest affects the incretin effect, 10 healthy nonobese male volunteers underwent 8 days of strict bed rest. B...

In order to test the hypothesis that endogenous opiates are at least partially responsible for hyperinsulinaemia in patients with polycystic ovarian disease (PCOD), the effect of naloxone (an opiate receptor blocker) on the insulin response to oral glucose load (OGTT) was studied in 20 women with PCOD and 17 control subjects at days 5-8 of their follicular phase. After fasting overnight for 10-...

INTRODUCTION The objectives of our study were to investigate whether fibroblast growth factor-21 (FGF-21) is involved in short-term regulation of glucose and the change of FGF-21 after metformin use in diabetic subjects. MATERIAL AND METHODS 43 subjects were recruited in the study, including 27 new-onset type 2 diabetes patients (nT2DM). A 75 g oral glucose tolerance test (OGTT) was administe...

Considering old GDM diagnostic criteria, alterations in insulin secretion and action are present in women with GDM as well as in women with one abnormal value (OAV) during OGTT. Our aim is to assess if changes in insulin action and secretion during pregnancy are related to 1-hour plasma glucose concentration during OGTT. We evaluated 3 h/100 g OGTT in 4,053 pregnant women, dividing our populati...

Drugs that inhibit the uptake of serotonin at the synaptic level, such as doxepin, are able to counteract hyperinsulism-induced hypoglycemia. Thus, we postulated that tianeptine, a drug which facilitates the uptake of serotonin at both synaptic and platelet levels, might display an antidiabetogenic effect. We investigated the oral glucose tolerance test (OGTT) + placebo in 38 normal humans. A s...

Highly informative yet simple protocols to assess insulin secretion and action would considerably enhance the quality of epidemiological and large-scale clinical trials. In an effort to develop such protocols, a 5-h, 11-sample oral glucose tolerance test (OGTT) was performed in 100 individuals and a 7-h, 21-sample meal in another 100. Plasma glucose, insulin, and C-peptide concentrations were m...

BACKGROUND Cardiac syndrome X (CSX) is characterized by angina pectoris but with patent coronary arteries. Our previous study demonstrated that subjects with CSX had a higher fasting insulin-resistance (IR) than the controls. However, few studies have investigated the degree of IR, including oral glucose tolerance test (OGTT)-derived indices and profiles of metabolic abnormalities between CSX a...

The significant threshold values for the 75-g oral glucose tolerance test (oGTT) during pregnancy have yet to be conclusively determined. This study aimed to identify the risk significance of various set thresholds for the oGTT result. Women undergoing a 75-g oGTT during the third trimester of pregnancy were classified into three groups: mild gestational impaired glucose tolerance (GIGT; 2-h po...

In order to evaluate the acute insulin response after i.v. injection of glucagon in polycystic ovary syndrome (PCOS), 35 women affected by PCOS and 11 normo-ovulatory controls underwent a 75 g oral glucose tolerance test (OGTT) and, 2 days later, a glucagon test (1 mg i.v.). Patients were analysed according to their degree of obesity; the insulin release after glucagon injection for lean PCOS s...