
study of phosphate excretion by the stop-flow
technique
m. de myttenaere
the stop-flow technique has been applied to the dog in an attempt to
rule out tubular secretion of phosphate and to locate the site of action of
parathyroid hormone (p.t.h.) on the renal tubule.  under the experimental
conditions used, no significant inward transtubular movement of p32 could be
demonstrated, ruling out tubular secretion of phosphate.  stop-flow
experiments performed in parathyroidectomized dogs before and after p.t.h.
administration demonstrated inhibition of phosphorus reabsorption by the
hormone.  in addition, the stop-flow pattern indicated that this
phenomenon took place mainly in the distal part of the proximal tubules.
