The effects of alterations in thyroid hormone status on secretion of gastrin in the adult rat and dog were studied to better understand previously reported changes in gastric secretion following hypophysectomy. Administration of triiodothyronine (T3) increased serum levels of gastrin in fed rats and both basal and fed gastrin levels in dogs. In T3-treated rats, antral gastrin and somatostatin levels were reduced significantly (P<0.05), whereas gastrin-releasing peptide (GRP) levels were increased. These data suggest that T3-treatment increases gastrin release by reducing antral concentrations of somatostatin and increasing antral concentrations of gastrinreleasing peptide, two peptides that are thought to participate in the regulation of gastrin secretion. Thyroidectomy significantly (P<0.05) decreased the serum gastrin response to food ingestion but did not affect basal levels ofgastrin in fasted rats. Thyroidectomy also significantly decreased serum levels of gastrin stimulated by gastrin-releasing peptide in fed rats.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)