Plasma gastrin and somatostatin in newborn infants and their relationship to catecholamines

We investigated the relationship between gastrin and somatostatin, and catecholamine concentrations in the cord blood of newborn infants. We also measured the levels of the two peptides during the first postnatal hours in the infants and furthermore characterized their molecular pattern. Twenty-two healthy infants who had been born at term were studied. Blood samples were collected from the umbilical cord and from the infants 0.5 h and 3.5 h after delivery. Peptides were measured with radioimmunoassay and further characterized by HPLC. Catecholamines were analysed by HPLC. We found that gastrin and somatostatin concentration in the umbilical cord blood was 106 +/- 40 pmol/l and 29 +/- 17 pmol/l, respectively. A significant relationship between the concentrations of somatostatin and noradrenaline in cord blood was found, (r = 0.7, n = 11, P less than 0.01). No such relation was found for gastrin. No change occurred in gastrin concentrations postnatally. Somatostatin concentration in the blood collected from the infant 0.5 h and 3.5 h after delivery was 19 +/- 11 pmol/l and 16 +/- 7 pmol/l, respectively. These concentrations were significantly lower (P less than 0.01) compared to the level measured in cord blood. Circulating gastrin was found to correspond to non-sulphated gastrin-34 and somatostatin to both somatostatin-28 and somatostatin-14. The proportion of somatostatin-28 was 30-40% and of somatostatin-14, 60-70%. We conclude that the somatostatin level, but not the gastrin level is influenced by the degree of fetal stress during labour, as evidenced by the relationship with noradrenaline. The gastrin level remained unchanged during the 3.5 h following delivery, whereas the somatostatin level decreased significantly during the same time.