Metabolic correlates of behaviour in the newborn infant.
Twenty-four infants were submitted to behavioural observation 0.5 and 3.5 h after birth. Blood samples were collected from the umbilical cord and from the infant immediately following observation, for the determination of glucose, insulin, cholecystokinin (CCK), and free fatty acids (FFA). It was found that 88% of the infants were awake and 83% performed sucking movements 0.5 h after birth; these findings were associated to a decrease in the plasma glucose concentration (p = 0.05). Eighty-eight percent of the infants were asleep and only 12% exhibited sucking movements 3.5 h after birth; at this time point there was an increase in the plasma concentrations of both CCK (p = 0.05) and FFA (p = 0.01). The infants' plasma insulin concentrations remained unchanged during the time course. It is suggested that the initial behavioural pattern of the newborn, characterized by the appearance of sucking movements, may be due to the rapid decrease of the circulating glucose concentration. The successive increase in the blood concentrations of both CCK and FFA might be two of the factors contributing to the cessation of sucking and to the establishment of a sleeping state.
Marchini
G
G
Department of Pediatrics KS-St. Göran, Karolinska Hospital, Stockholm, Sweden.
Persson
B
B
Uvnäs-Moberg
K
K
D001143:Arousal / Q000502:physiology*; D001786:Blood Glucose / Q000378:metabolism; D002766:Cholecystokinin / Q000097:blood; D004734:Energy Metabolism / Q000502:physiology*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D006801:Humans; D007231:Infant, Newborn / Q000502:physiology*; D007328:Insulin / Q000097:blood; D008297:Male; D012016:Reference Values; D013391:Sucking Behavior / Q000502:physiology*; D014851:Wakefulness / Q000502:physiology
D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D002766:Cholecystokinin