Plasma Levels of Total and
Active Ghrelin in Acromegaly and Growth Hormone Deficiency
Z. JARKOVSKÁ, M. ROSICKÁ, J. MAREK, V. HÁNA, V.
WEISS, V. JUSTOVÁ, Z. LACINOVÁ, M. HALUZÍK, M. KRŠEK
Third Department of Medicine, First Faculty of Medicine, Charles
University, Prague, Czech Republic
Received February 22, 2005
Accepted April 26, 2005
On-line May 24, 2005e
Summary
Ghrelin is an endogenous growth hormone (GH) secretagogue
recently isolated from the stomach. Although it possesses a
strong GH releasing activity in vitro and in vivo, its
physiological significance in endogenous GH secretion remains
unclear. The aim of this study was to characterize plasma
ghrelin levels in acromegaly and growth hormone deficiency
(GHD). We investigated plasma total and active ghrelin in 21
patients with acromegaly, 9 patients with GHD and 24 age-, sex-
and BMI-matched controls. In all subjects, we further assessed
the concentrations of leptin, soluble leptin receptor, insulin,
IGF-I, free IGF-I and IGFBP-1, 2, 3 and 6. Patients with
acromegaly and GHD as well as control subjects showed similar
levels of total ghrelin (controls 2.004±0.18 ng/ml, acromegalics
1.755±0.16 ng/ml, p=0.31, GHD patients 1.704±0.17 ng/ml, p=0.35)
and active ghrelin (controls 0.057±0.01 ng/ml, acromegalics
0.047±0.01 ng/ml, p=0.29, GHD patients 0.062±0.01 ng/ml,
p=0.73). In acromegalic patients plasma total ghrelin values
correlated negatively with IGF-I (p<0.05), in GHD patients
active ghrelin correlated with IGF-I positively (p<0.05). In the
control group, total ghrelin correlated positively with IGFBP-2
(p<0.05) and negatively with active ghrelin (p=0.05), BMI
(p<0.05), WHR (p<0.05), insulin (p=0.01) and IGF-I (p=0.05).
Plasma active ghrelin correlated positively with IGFBP-3
(p=0.005) but negatively with total ghrelin and free IGF-I
(p=0.01). In conclusion, all groups of the tested subjects
showed similar plasma levels of total and active ghrelin. In
acromegaly and growth hormone deficiency plasma ghrelin does not
seem to be significantly affected by changes in GH secretion.
Key words
Total ghrelin • Active ghrelin • Leptin • Acromegaly • Growth
hormone deficiency
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