GASTROINTESTINAL WATER AND ELECTROLYTES. I. THE EQUILIBRATION OF RADIOSODIUM IN GASTROINTESTINAL CONTENTS AND THE PROPORTION OF EXCHANGEABLE SODIUM (Nae) IN THE GASTROINTESTINAL TRACT 1

GASTROINTESTINAL WATER AND ELECTROLYTES. II. THE EQUILIBRATION OF RADIOPOTASSIUM IN GASTROINTESTINAL CONTENTS AND THE PROPORTION OF EXCHANGEABLE POTASSIUM (Ke) IN THE GASTROINTESTINAL TRACT 1

“…In contrast, the rate of stool sodium excretion averages 0.4 mEq. per day, which is only 2.6 per cent of the "total" intraluminal sodium content (4).…”

“…At the time of radioassay the resultant mixture of K' (half-life, 12.4 hours) and K" (half-life, 22 collected for assay of radioactivity and chemical analyses cate dilutions of the separate gastrointestinal contents as described in the first paper in this series (4). In using a lithium internal standard flame photometer.…”

“…The gross and microscopic postmortem findings were subsequently recorded. The techniques employed in collecting and analyzing the gastrointestinal contents are described in the first report in this series (4) ; the appendix to the first report summarizes the pertinent features of the case histories of these subjects.…”

“…The value of this ratio is assumed to represent the fraction of gut potassium which was exchanged (4,13).…”

“…The first paper in this series (4) reported the results of measurement of intraluminal gastrointestinal sodium content in rabbits and in human subjects studied postmortem. The present study is similar in design and execution to the study on gastrointestinal sodium content and presents observations on a) the amount of intraluminal gastrointestinal potassium relative to total exchangeable potassium (Ke) and the extent of radiopotassium exchange equilibrium in gastrointestinal contents in rabbits and b) the amount of intraluminal gastrointestinal potassium in human subjects studied postmortem.…”