Obesity is associated with an impairment of the growth hormone secretion elicited by all stimuli known to date, but the basic mechanism of the alteration is unknown to date, but the basic mechanism of this alteration is unknown. To determine
whether
obesity is associated with a chronic state of tonic somatostatin secretion, several tests with growth hormone stimuli such as GHRH(1 ㎍/kg), clonidine(150 ㎍/㎡)and Regular insulin (0.1U/kg, subcutaneously), to obese subjects and normal control
with or
without pyridostigmine were undertaken, and the Somatomedin-c levels were measured in both obese subjects and matched controls.
1) The peak GH levels and AUC-GH after administration of GHRH, Clonidine or Regular insulin in obese group is less than those in control group.
2) Pretreatment with pyridostigmine increased the peak GH levels and AUC-GH significantly in obese group but the absolute values are less than those of normal group.
3) The Somatomedin-c levels are significantly higher in obese group than control.
Our results lend support to the view that chronically high level of somatostatin decreases the responsiveness to GHRH and secretion itself.
|