Umbilical cord ghrelin concentrations in Asian and Caucasian neonates

Objectives: To compare the relationship between cord plasma ghrelin and growth hormone (GH) concentrations and birth weight in Asian and Caucasian neonates. Methods: We measured umbilical cord ghrelin and GH concentrations in 180 full-term newborns [4 groups of 45 according to ethnicity (Caucasian/Asian) and sex]. Results: Ghrelin was detectable in all umbilical cord samples (mean +/- SD: 611 +/- 267, range 193-2,010 pg/ml). There was no significant difference in ghrelin concentrations between Asian and Caucasian male or female neonates. In contrast, GH values were significantly affected by sex (p = 0.001) and ethnicity (p = 0.006). Except for a weak (r = -0.33, p < 0.03) negative correlation between ghrelin and GH in male Caucasian neonates, ghrelin and GH concentrations were independent. Conclusions: Umbilical cord concentrations of ghrelin, a potent orexigenic and GH stimulatory agent, are similar in Caucasian and Asian newborns, suggesting that ghrelin does not play a causal role in the differences in body composition and GH metabolism observed in these neonates.