A simple method for measuring of intestinal solute transport in mucosal biopsy specimens

Accurate in vitro measurements of intestinal mucosal solute uptake in human s are often difficult because only small amounts of tissue material are ava ilable. We describe a miniaturized everted sleeve method of measuring intes tinal solute uptake in endoscopy biopsy samples that combines simplicity, g ood tissue viability and reproducibility. Biopsies were mounted on a dressm aker needle head stationed immediately over a stirring bar rotating at 1200 rpm. This approach was used to measure taurocholate uptake in sheep and hu man endoscopy biopsies. Comparison was made to conventional standardized ev erted sleeve preparations. Na+-dependent uptake rates correlated well among individual sheep (R 0.88, P < 0.05). There was excellent correlation betwe en conventional and biopsy preparations in humans (R-2 0.98; P < 0.05). The biopsy method overestimated diffusional uptake rates in sheep and humans b y two to three fold when compared to conventional everted sleeve preparatio ns. We conclude that this method is valuable to measure Na+ dependent solut e uptake rates in biopsy samples from human intestine.