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Updated: Aug 11, 2026

Mechanisms Underlying Gut Hormone Secretion Using the Isolated Perfused Rat Small Intestine
Published on: February 26, 2019
Sodium secretion as part of the formation of gastric juice
Abstract:
Experiments with Heidenhain pouch dogs showed the well known high sodium concentrations at low secretion rates and low sodium concentrations at high ones after stimulation with a continuous intravenous injection of histamine. It was previously thought that the primary secretion did not contain any sodium, but that all the sodium present in the gastric juice appeared as a result of diffusion. A more detailed analysis of the experimental data showed, however, that there is in fact sodium present also in the primary juice in the small concentration of 3-5 mEq/l. The origin of the secreting volume containing this concentration of sodium is unknown.
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