Abstract
The buffering activity of the human rectum was evaluated in various pilot studies, using a rectal lumen perfusion method. Quantitative alkaline and acid secretion was measured, respectively, by direct titration according to the pH-stat method. The change in composition of the perfusate with regard to the test drug benzoate and the concentration HCO −3 was detected. The pilot studies suggest that rectal mucosa is capable of neutralizing a pH deviating from the physiological value within a remarkably short time. In the acid region, at least a part of the alkalizing activity is the result of HCO −3 secretion. It has been shown that this process is stimulated by the H− as well as Cl− ions. In the basic region neutralization very likely occurs by means of H− secretion.
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Böttger, W.M., Schoonen, B.J.M., Moolenaar, F. et al. A study on the buffering activity of the human rectum. Pharmaceutisch Weekblad Scientific Edition 11, 9–12 (1989). https://doi.org/10.1007/BF01972908
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DOI: https://doi.org/10.1007/BF01972908