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Background/Aims: Central dopaminergic activity is probably linked to regulation of glucose and lipid metabolism and weight maintenance. The aim of our study was to evaluate the relationship between central dopaminergic activity measured using the apomorphine challenge test and metabolic parameters in healthy men. Methods: Forty-two healthy men (average age 43.5 ± 7.4 years, body mass index, BMI, 27.4 ± 5.7) were examined anthropometrically and biochemically (glycemia, lipids, glycated hemoglobin). Central dopaminergic activity was assessed as the area under the curve (AUC) of prolactin (PRL) and growth hormone (GH) responses to the apomorphine challenge test after sublingual administration of apomorphine in a dose of 0.033 mg/kg. Insulin resistance was quantified by calculation of glucose disposal and metabolic clearance rate during a euglycemic hyperinsulinemic clamp on two insulin levels (1 and 10 mIU/kg/min). Linear regression was used for statistical analysis. Results: Hormonal responses correlated negatively with age (for AUC/GH r = -0.33; p = 0.031) and BMI (AUC/GH r = -0.41; p = 0.007). After adjustment for age and BMI, a statistically significant negative correlations between AUC/PRL and total cholesterol (r = -0.41; p = 0.007), AUC/GH and HbA1c (r = -0.37; p = 0.016) and AUC/GH and HOMA (homeostasis model assessment; r = -0.345; p = 0.025) were observed. Conclusion: Central dopaminergic activity declines with age and BMI. Higher total cholesterol, glycated hemoglobin and insulin resistance parameters are connected with lower central dopamine tone. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

A considerable variability in the incidence and prevalence of diabetic nephropathy (DN) coheres with an important contribution of multigenetic predisposition in the development of DN. Some genes, which probably participate in the pathogenesis of diabetic nephropathy, also play a role in the regulation of blood pressure, familial hyperlipidemia, familial hypertension and other diseases of the cardiovascular system. We have examined the association of diabetic nephropathy, nephropathy of non-diabetic origin, hypertension and of type 2 diabetes itself with several genetic polymorphisms (the insertion/deletion polymorphism in the gene for angiotensin-converting enzyme, the G/T polymorphism in the glucose transporter 1 gene, the G/T (894) polymorphism and the T/C (−786) polymorphism in the eNOS gene in three groups of patients with diabetes mellitus: 1) patients without diabetic nephropathy (DM); 2) patients with DN; 3) patients with nephropathy of non-diabetic origin (NDRD). Angiotensin-converting enzyme is an important factor in a development of arterial hypertension, but in our groups of Central European diabetic patients the I/D polymorphism was not associated with diabetic nephropathy. Furthermore, we have confirmed that the T/C (T786C) polymorphism in the eNOS gene is associated with metabolic syndrome including type 2 diabetes. [ABSTRACT FROM AUTHOR]