Plasma Big Gastrin and Gastric Secretion in Newborns and Infants: Part 1: Plasma Big Gastric Secretion in Normal Newborns and Infants

Abstract

AbstractTo elucidate the development of the gastric secretion and the role of gastrin in the secretion in early childhood, big gastrin and gastrin immunoreactivities in fasting plasma, and basal and maximal gastric secretions stimulated by pentagastrin were measured in 17 newborns and 15 infants.By pentagastrin stimulation, the gastric acid and pepsin outputs significantly increased in preterms, terms and infants. However, the response to the stimulation was very weak in preterms and gradually increased with age. The secretion of gastric juice, and the output of acid and pepsin showed significant correlations with body weight. The maximal values of these three factors after the stimulation showed better correlations than the basal values. Big gastrin was predominant among circulating gastrins. Inverse relationships were obtained between the pH of gastric juice and plasma gastrin levels, and between the basal gastric acid output and plasma gastrin and big gastrin levels.These findings suggest that newborn parietal and chief cells are responsive to pentagastrin soon after birth and a negative feedback mechanism between gastric acid and plasma gastrins may be already established in early childhood as well as in adults.