Mìžnarodnij Endokrinologìčnij Žurnal (Aug 2018)
Ghrelin content in blood plasma of children with syndrome of biologically inactive growth hormone
Abstract
Background. In the world literature, information on the state of the system of growth hormone/growth factors (GH/IGF-1), in particular regarding the relationship of GH/IGF-1/grelin, in patients with short stature is extremely limited. The purpose of the study was determination of the features of ghrelin secretion in patients with syndrome of biologically inactive growth hormone compared to that in children with somatotropic insufficiency. Materials and methods. The ghrelin (Ghr) concentration was determined in 33 patients with short stature, among them 22 patients with somatotropic insufficiency and 11 patients with biologically inactive growth hormone syndrome. The passport age of all the examined patients corresponded to the range of puberty. The bone age retarded from the passport age for more than 2 years in both groups. The growth retardation in all the children was minus 2SD. The control group consisted of 6 healthy children. Basal levels of the growth hormone (GH) and insulin-like growth factor 1 (IGF-1), GH level during night-time excretion and clonidine-stimulating test were determined in all examined children. At the same time blood samples were obtained for studying the Ghr level. Results. The most significant changes in the Ghr level were detected in 90 minutes after falling asleep in all subjects. A significant increase in Ghr levels in children with syndrome of biologically inactive growth hormone, somatotropic insufficiency, and in control group compared to baseline and maximum release during the clonidine test was established. Thus, the nightly level of Ghr exceeded basal level by 1.4 times in children with somatotropic insufficiency, by 3.4 times — in children with syndrome of biologically inactive growth hormone and by 2.8 times — in children of the control group. We did not establish a link between IGF-1 and ghrelin in all of the examined children. Conclusions. In patients with syndrome of biologically inactive growth hormone and somatotropic insufficiency, a significant release of ghrelin was detected in the first hours after falling asleep. No correlation between the levels of ghrelin and IGF-1 was found in patients with syndrome of biologically inactive growth hormone, somatotropic insufficiency and in healthy children. The administration of clonidine does not induce the significant changes in the ghrelin level of patients with short stature and in healthy children.
Keywords
