AJP - Gastrointestinal and Liver Physiology, Vol 238, Issue 4 376-G383, Copyright © 1980 by American Physiological Society
Effect of chemically defined diets on antral and serum gastrin levels in rats
B. Sircar, L. R. Johnson and L. M. Lichtenberger
When rats were fed isocaloric amounts of chemically defined diets with
variable amounts of protein (8-60%) or fat (0-30%) over a 10-day period,
their serum and antral gastrin concentrations were, respectively, 60 and
40% lower than the levels of chow-fed rats. It was also determined that
neither the low bulk content of these diets nor their inability to
adequately buffer the gastric pH contributed to this response. The time
course of this dietary-induced reduction in gastrin levels was investigated
and it was found that the serum hormone levels were significantly reduced
as early as 1-2 h after chow-fed rats were placed on these chemically
defined diets. Antral gastrin levels were maintained at normal levels for
4-5 days after rats started consuming these synthetic diets and fell
thereafter. With all of the chemically defined diets tested, the gastrin
secretory response to a meal was significantly reduced. It therefore
appears that synthetic diets lack some undefined food constituent present
in chow that is required for the normal postprandial release of gastrin or,
alternatively, that they contain an inhibitory factor which blocks the
normal secretory response.
