AJP - Gastrointestinal and Liver Physiology, Vol 256, Issue 6 975-G978, Copyright © 1989 by American Physiological Society
Gastric acid secretion and parietal cell mass: effects of thyroidectomy and thyroxine
K. O. Adeniyi and M. O. Olowookorun
Department of Human Physiology, Faculty of Medical Sciences, University of Jos, Nigeria.
The role of thyroid hormones on parietal cell function and number was
studied in the rat. Chronic administration of thyroxine (6-8 micrograms/100
g body wt/day) for 35 days significantly increased parietal cell mass (from
21.18 +/- 0.13 x 10(6) to 26.71 +/- 0.14 x 10(6] as well as basal acid
secretion (from 3.69 +/- 0.08 to 4.99 +/- 0.16 mueq/10 min) and
histamine-stimulated acid secretion (from 2.45 +/- 0.12 to 3.69 +/- 0.21
mueq/10 min). Thyroidectomy decreased the number of parietal cells in the
gastric mucosa (to 10.48 +/- 0.09 x 10(6] and basal acid secretion (to 3.09
+/- 0.08 mueq/10 min). Histamine (0.2 mg) injection into the
thyroidectomized rats increased acid secretion by only 1.41 +/- 0.06
mueq/10 min as against 2.45 +/- 0.12 mueq/10 min obtained for control rats.
The results suggest that thyroid hormones regulate basal and
secretagogue-stimulated acid secretion via their effects on parietal cell
mass.
