title: A study on the buffering activity of the human rectum. In vivo demonstration of HCO3- and H+ secretion after rectal application of fluids with an unphysiological pH.
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 HCO3- 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 HCO3- 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.
authors.affiliation: St. Maartens Hospital, Venlo, The Netherlands.
authors.forename: W M
authors.initials: WM
authors.lastname: Böttger
authors.forename: B J
authors.initials: BJ
authors.lastname: Schoonen
authors.forename: F
authors.initials: F
authors.lastname: Moolenaar
authors.forename: J
authors.initials: J
authors.lastname: Visser
authors.forename: D K
authors.initials: DK
authors.lastname: Meijer
mesh_terms: D001639:Bicarbonates / Q000378:metabolism*; D002021:Buffers; D006801:Humans; D006863:Hydrogen-Ion Concentration; D011522:Protons; D012007:Rectum / Q000378:metabolism*
chemical_list: D001639:Bicarbonates; D002021:Buffers; D011522:Protons