Effect of Mercuhydrin on sodium transport in proximal tubules of dogs in stop flow

Abstract

When Na22 is infused into a renal artery under stop-flow conditions in a dog in mannitol diuresis, little or no movement of sodium from plasma into tubule lumen occurs distal to the tubule site of production of the sodium trough, whereas the more proximal walls are highly permeable to sodium. Sodium flux across proximal walls is increased by Mercuhydrin. This is interpreted as evidence for increase in passive leak, which is presumed to be partially or wholly responsible for the natriuretic effect.