This study has been designed to investigate, in five non-insulin-dependent diabetic patients, the influence of physical training (1 h a day, 7 days a wk for 6 wk, at 50-60% maximum oxygen uptake) on blood glucose control, glucose tolerance, insulin secretion, and insulin action. Physical training resulted in a significant improvement in blood glucose control, glucose tolerance, and insulin action. These results suggest that short-term intense physical training ameliorates the main metabolic derangements of non-insulin-dependent diabetes mellitus.

Hyperthyroidism is considered to be an insulin-resistant state, but a quantitative evaluation of some action of insulin is still lacking. We performed euglycaemic clamp at about 350 and 7000 pmol l-1 plasma insulin concentration in combination with the 3H-glucose infusion in 12 patients with Graves' disease and in 12 matched controls. Fasting plasma insulin (126 +/- 6.5 vs. 77.5 +/- 5.7 pmol l-1; P less than 0.001), C-peptide (502 +/- 36 vs. 363 +/- 41 pmol l-1; P less than 0.001) and glucagon (47 +/- 3.3 vs. 33.3 +/- 3 pmol l-1; P less than 0.01) were significantly higher in hyperthyroids than in euthyroids. Basal hepatic glucose production was significantly higher in hyperthyroids than in euthyroids (18.3 +/- 1.4 vs. 9.2 +/- 0.5 mumol l-1; P less than 0.0001), and its suppression during physiological hyperinsulinaemia was only 50% in hyperthyroids. Glucose utilization and suppression of lipolysis were normally stimulated by insulin. All parameters altered during hyperthyroidism were normalized during methimazole-induced euthyroidism. We conclude that insulin resistance involves mainly glucose rather than lipid and is selective at the hepatic level.

The 1-yr incidence of insulin-dependent diabetes mellitus (IDDM) in a population of the Piedmont and Aosta Valley area of Italy was recorded. Anti-virus antibodies (e.g., Coxsackie B1-6, mumps, cytomegalovirus), islet cell antibodies (ICAs), and HLA-A, -B, -C, and -DR were determined in 74 IDDM patients (38 males, 36 females) and in controls. Total IDDM incidence was 5.0/100,000, and the incidence for those less than 20 yr of age was 11.6/100,000. Anti-virus antibody frequency was not different in IDDM patients and controls. ICAs were present in 58% of IDDM patients at onset and in 30% after 12 mo, and complement-fixing ICAs were found in 39 and 17%, respectively. IDDM was significantly and positively associated with DR3/DR4 and negatively associated with DR2 and DR5. ICA frequency was significantly higher in DR3/DR4 heterozygote patients than in patients without DR3 and DR4. These results suggest that in this IDDM population viral etiology is not evident, ICAs offer only a partial pathogenetic explanation, and genetic and immunologic heterogeneity is evident.

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As reported by other workers, late pregnancy is accompanied by an insulin-resistant state, which is not clearly explained by rising of the so-called gestational hormones. The present study reports the results on insulin binding and insulin action on adipocytes from healthy, obese and diabetic pregnant women (17 s.) isolated during Caesarian section and in control non pregnant women (22 s.). Because plasma insulin increases during pregnancy, the hypothesis of a down regulation of insulin-receptor by circulating insulin is confirmed by this research.