Transmural Ionic Fluxes and Electrical Potential Difference in the Human Jejunum During Perfusion with a Dihydroxy Bile Acid

Abstract

Perfusion studies of the proximal jejunum were performed in healthy volunteers to define the influence of glycochenodeoxycholic acid (GCDC) 2.5 mmol/l on the net movements of water and electrolytes, the bidirectional fluxes of sodium, potassium, and chloride, and the transmural electrical potential difference (PD). The flux data supported the notion that active sodium transport is inhibited by luminal GCDC, which on the other hand elicits active secretion of chloride. PD was 3±1 mV, lumen negative, and was not influenced by GCDC. The flux data fit a previously proposed model for the GCDC effect.

Key-words:

• Absorption, intestinal
• bile acids
• biological transport, active
• cell membrane permeability
• electrolytes
• membrane potentials
• perfusion
• water movement