Phenolsulfonphthalein test in healthy sheep and in sheep with reductions in functional renal mass
Filippich, L.J.; English, P.B.; Ainscow, J.
American Journal of Veterinary Research 46(3): 733-738
1985
ISSN/ISBN: 0002-9645 PMID: 3994140 Document Number: 242385
The phenolsulfonphthalein (PSP) plasma clearance and urinary excretion tests were applied to six sheep before and after 50% and 75% reductions in functional renal mass. The PSP determinants found most useful as indicators of renal mass reduction were the 15-minute urinary excretion percentage and the 60-minute (PSP60) plasma concentration. Although both of these determinants could be used to detect renal mass reduction, the 15-minute PSP excretion percentage was the more sensitive. The PSP60 value was influenced by factors other than reduced nephron numbers; the contraction of the PSP volume of distribution that occurred after renal mass reduction was one important influencing factor. Overall, the PSP tests more accurately reflected the volume of blood delivered to the kidney than the proximal tubular secretory capacity.