Peptide YY release in anorectic patients after liquid meal

Fasting and postprandial levels of human peptide YY (PYY) were recently found to be lower in obesity. To investigate whether PYY levels are correspondingly high in patients with anorexia nervosa, PYY concentrations were analyzed under basal conditions and in response to a liquid meal. We investigated PYY plasma levels in 16 female anorectic (BMI 15.2±0.3 kg/m²) and seven lean subjects (BMI 21.3±0.6 kg/m²) before and after ingestion of a liquid meal (250 kcal; 15% protein, 55% carbohydrates, and 30% fat). PYY levels were analyzed using PYY ELISA (DSL, USA). Values are given as mean±SEM. Basal PYY levels in anorectic patients (89.0±14.4 pg/mL) were not significantly different from lean subjects (64.1±12.1 pg/mL). Postprandial PYY levels in healthy volunteers increased significantly after 20 and 60 min (80.4±12.7 and 96.0±19.9 pg/mL, respectively). In anorectic women PYY was increased at 20 min (137.9±19.5 pg/mL) and at 60 min (151.3±19.2 pg/mL). No difference was found between both groups. We conclude that basal and postprandial PYY levels in normal weight women are not different from anorectic patients. We could not confirm the recently published blunted postprandial PYY response in anorexia, a finding that merits further study.