title: Central dopaminergic activity influences metabolic parameters in healthy men.
abstract: OBJECTIVE
  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.
  
  
  CONCLUSIONS
  Central dopaminergic activity declines with age and BMI. Higher total cholesterol, glycated hemoglobin and insulin resistance parameters are connected with lower central dopamine tone.
authors.affiliation: Diabetologic Center, Second Department of Internal Medicine, Faculty Hospital Kralovske Vinohrady and Third Faculty of Medicine, Charles University, Prague, Czech Republic. Brunerova@seznam.cz
authors.forename: Ludmila
authors.initials: L
authors.lastname: Brunerova
authors.forename: Jana
authors.initials: J
authors.lastname: Potockova
authors.forename: Jiri
authors.initials: J
authors.lastname: Horacek
authors.forename: Jiri
authors.initials: J
authors.lastname: Suchy
authors.forename: Michal
authors.initials: M
authors.lastname: Andel
mesh_terms: D000328:Adult; D001058:Apomorphine / Q000494:pharmacology; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D002490:Central Nervous System / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D004298:Dopamine / Q000378:metabolism / Q000494:pharmacology; D018491:Dopamine Agonists / Q000494:pharmacology; D059290:Dopaminergic Neurons / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D004734:Energy Metabolism / Q000187:drug effects; D006262:Health; D006801:Humans; D007328:Insulin / Q000097:blood / Q000378:metabolism; D007333:Insulin Resistance / Q000502:physiology; D008297:Male; D008875:Middle Aged
chemical_list: D001786:Blood Glucose; D018491:Dopamine Agonists; D007328:Insulin; D001058:Apomorphine; D004298:Dopamine