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Ghrelin in the foetus, neonate and infant: Ghrelin, which is secreted by cells in a number of sites including stomach, hypothalamus, placenta, testis and pancreas, has GH-secreting and orexigenic properties. Recent data show an effect on insulin secretion and a direct role in metabolic regulation and energy balance. Using immunohistochemical and ghrelin-mRNA methodologies, ghrelin has been identified in a unique population of islet cells in foetal, neonatal and adult pancreas. These cells (which do not express any other known islet hormones) were in good supply in the foetus and neonate (10% of all endocrine cells between mid-gestation and early postnatal period) but were far less common in adults. Furthermore, at mid-gestation pancreatic ghrelin cells outnumbered gastric ghrelin cells. Postnatal studies into the relationship between ghrelin levels and one-year catch-up growth in SGA babies have revealed that infants who showed good catch-up had higher levels of the orexigenic ghrelin after an IV glucose load than those with poor catch-up, suggesting that a sustained orexigenic drive contributes to improved post-natal weight gain. Read more: Regul Pept 2002;107:63-9 J Clin Endocrinol Metab 2002;87:5830-3 |