Blood glucose, plasma insulin and glucagon response to arginine in infants during the first month of life.

Blood glucose, plasma insulin and plasma glucagon were determined during an arginine test at 0, 30 and 60 min in 1 to 7 and 30 day infants. The results were compared with those obtained in the 2-10-year-old children. Basal levels of blood glucose increased from the 1st to the 30th day; by the 30th day they were comparable with those observed in the 2-10-year-old children. Basal levels of plasma insulin were higher in 1 day infants, lower in 7 day infants and similar to those of the 2-10-year-old children in the 30 day infants. Basal values of plasma glucagon were higher in 1 day infants than in the 2-10-year-old children; the lowest levels were found in 7 day infants. After arginine, blood glucose increased in the 2-10-year-old children, the variations were negligible in the 1 to 7 and 30 day infants. Plasma insulin increased in 2-10-year-old children, there was a slight increase in 1 and 30 day infants and a negligible one in the 7 day infants. Plasma glucagon increased in the 2-10-year old children, and was similar in 1 day infants; the increase was reduced in 30 day infants and virtually absent in 7 day infants. These results suggest that there is a transitory alpha cell insensitivity to arginine during the first week of life.