Acute hyperinsulinemia is associated with increased plasma adrenomedullin concentrations in uncomplicated obesity.
OBJECTIVE
Adrenomedullin (AM) is a potent hypotensive peptide which may be implicated in the insulin regulatory system. Acute hyperinsulinemia exerts no influence on plasma AM in normal subjects while no data on obese subjects has been reported.


OBJECTIVE
The aim of the study was to investigate the effect of acute hyperinsulinemia on the plasma AM concentration in patients with uncomplicated obesity.


METHODS
We measured the plasma AM levels in 23 obese subjects (BMI 41.9 +/- 9.8 kg/m2), 21 females and 2 males (mean age 31 +/- 7.2 years), before and during a euglycemic hyperinsulinemic clamp. The control group consisted of 43 healthy subjects (HS) (22 males and 21 females; mean age 38 +/- 12 years; BMI 23.3 +/- 3.2 kg/m2).


RESULTS
Baseline plasma AM was found to be higher in obese subjects (20.4 +/- 8.4 pg/ml) than in normal subjects (11.3 +/- 0.8 pg/ml) (p < 0.001). A significant increase in the plasma AM levels was observed in obese subjects during acute hyperinsulinemia (from 20.4 +/- 8.4 pg/ml at 0 min to 26 +/- 8.9 pg/ml at 120 min, p < 0.02). Plasma AM concentrations were significantly correlated with insulin levels at 30 min (r = 0.44; p = 0.04) and 120 min (r = 0.40, p = 0.05) during the clamp.


CONCLUSIONS
In conclusion, acute hyperinsulinemia induced a significant increase in the plasma levels of AM in uncomplicated obese subjects. Hyperinsulinemia may, at least in part, regulate levels of AM in obesity, explaining the high levels of the peptide in these subjects.
Letizia
C
C
Internal Medicine, Department of Clinical Science, University of Rome La Sapienza, Rome, Italy. claudio.letizia@uniroma1.it
Iacobellis
G
G
Caliumi
C
C
Leonetti
F
F
Cotesta
D
D
Ribaudo
M C
MC
Petramala
L
L
Cianci
R
R
Celi
M
M
D'Erasmo
E
E
Di Mario
U
U
D000208:Acute Disease; D053607:Adrenomedullin; D000328:Adult; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood*; D008297:Male; D009765:Obesity / Q000097:blood*; D009994:Osmolar Concentration; D010455:Peptides / Q000097:blood*
D010455:Peptides; D053607:Adrenomedullin