Plasma leptin, insulin, and neuropeptide Y response to feeding in newborn infants.

Although the functions and regulation of leptin, insulin, and neuropeptide Y (NPY) are well studied, their role and regulatory mechanisms in neonates are poorly understood. We have reported that, compared with umbilical concentrations, on the 4th day of life fasting plasma leptin and insulin concentrations are significantly decreased, and plasma NPY concentrations increased.1 The effects of feeding on plasma concentrations of these hormones are controversial2,3 or have not been studied. We have investigated the effects of breast feeding on …