Plasma galanin concentrations in obese, normal weight and anorectic women

Objective: Galanin is believed to play a role in the control of eating behavior. No information is available on its concentrations in the biological fluids in human obesity, and this study aimed to clarify this. Measurements: We measured plasma galanin and serum insulin levels in 30 obese, 35 normal weight and 11 anorectic women. Results: Mean galanin values were quite similar in obese and control subjects (76.8 ± 3.20 vs 76.1 ± 2.33 pg/ml) and only slightly reduced in anorectic patients (67.9 ± 2.30 pg/ml). Insulin levels were significantly increased and decreased in obese and anorectic patients, respectively, compared to controls. Insulin correlated positively with BMI in the whole group of subjects studied (r = 0.72, P < 0.0001) and in the obese subgroup (r = 0.56, P < 0.02). No correlations could be detected between WH ratio, insulin and galanin concentrations and between galanin and BMI. Conclusions: In conclusion, plasma galanin concentrations appear to be comparable in obese, normal weight and anorectic subjects. This does not exclude a role of galanin in the regulation of eating behavior since variations of the peptide in discrete brain areas may not be detectable in general circulation and peripheral sources of the peptide may contribute to its plasma levels. Also, our data suggest that galanin does not play a major role in the regulation of insulin secretion in humans.