Endocrinology, Vol 100, 1014-1021, Copyright © 1977 by Endocrine Society

ARTICLES

Stimulation of gastrin secretion in the pig by parathyroid hormone and its inhibition by thyrocalcitonin

RM Bolman 3d, CW Cooper, SC Garner, PL Munson and SA Wells Jr

Gastrin secretion was studied in 16 young anesthetized pigs weighing 14- 26 kg. Test substances were infused (0.1 ml/min x 10-20 min) directly into the gastric antrum via a catheter in the right gastroepiploic artery. Samples were collected from a catheter in the right gastroepiploic vein and plasma gastrin was measured by radiommunoassay. The following results were observed: 1) basal gastrin in antral venous blood was 10-5 times that in peripheral blood (620+/-222 pg/ml vs. 41+/- 10 pg/ml, 2) native bovine parathyroid hormone (PTH) and synthetic human 1-34 PTH (0.02-4U/min) produced rapid (within 10-30 min) and pronounced (approximately 10-fold) increases in gastrin release with no increase in plasma calcium and, in several animals, in the face of a falling plasma calcium concentration, 3) neither acute thyroidectomy nor infusion of porcine thyrocalcitonin (TCT), 0.5-2.5 U/min) consistently altered basal gastrin secretion (N=3-6), and 4) infusion of TCT (0.5 U/min)along with PTH (2U/min) significantly suppressed the 10-11-fold increase in gastrin release observed when PTH subsequently was infused alone in each pig (N=6). The results demonstrate that PTH can stimulate gastrin secretion in the pig and that TCT can suppress this effect.