Electrophysiological study of renal papilla of golden hamsters

¹ Institute of Biological Chemistry, University of Copenhagen, Copenhagen, Denmark

Electrical potential differences across the tubular epithelium of loops of Henle and of collecting ducts were measured by microelectrode techniques. In a separate series of experiments concentrations of Na²² and of chloride were estimated in fluid collected from Henle's loop and in vas rectum plasma at corresponding cross-sectional levels of the papilla. The lumen of thin ascending limbs of Henle's loop was found electrically more negative (mean: –11 mv), with respect to interstitial fluid, than the lumen of thin descending limbs (–3 mv). No chemical driving force for reabsorptive net diffusion of sodium chloride was found across the wall of thin limbs of Henle's loop. The magnitude of the electrical potential differences observed across the collecting duct epithelium (mean: –14 mv) indicates the existence of active transport of both sodium and chloride across this part of the terminal nephron.

Key Words: tubular epithelium electrical potential • tubular sodium transport • tubular chloride transport • Henle's loop

Submitted on September 3, 1963