Ghrelin, Obestatin and Their Receptors As Well As Metabotropic Glutamate Receptor Assessment in Chronic Functional Constipation in Children.

Abstract

The aim of this study was to examine the role of ghrelin, obestatin, and glutamate and their receptors in the pathogenesis of children functional constipation. Children ages 4-17 were the subject of the study: 121 children with constipation (55 boys and 66 girls), 36 patients of the same age (26 boys and 10 girls) were the controls. Expression of ghrelin, obestatin, and glutamate receptors on gastric and colon specimens taken by endoscopy were assessed. The concentration of the above agents was estimated in serum by the enzyme-linked immunosorbent assay test. The lower median serum concentrations of ghrelin, in the constipated children than in controls were confirmed (1.9 ng/mL vs 2.6 ng/mL, P < 0.05). The expression of the metabotropic receptor 7 for glutamate (mGlu7) RNA was higher in the stomach (32.49 vs 31.47, P < 0.05), and was lower in the rectum in constipated patients compared to the control group (31.76 vs 32.62, P < 0.05). A negative correlation between the concentration of ghrelin in serum and colonic transient time (P = 0.01, rho = -0.23) was shown in the study group.Higher median expression of obestatin receptor G protein-coupled receptor39 in rectal mucosae was found in a constipated group than in the controls (29.9 vs 26.9, P < 0.05). Ghrelin, and receptors for ghrelin, obestatin, and glutamate in gastrointestinal mucosa play a role in the pathogenesis of functional constipation in children.