<prompt> PAH is used to measure?Extracellular fluidGlomerular filtration rateRenal plasma flowPlasma value  <response>: Ans. isci.e., Renal plasma flow Rel Ganong 248e p, 678-679A substance which closely satisfies this description is para-aminohippuric acid PAH, Therefore,PAH is used to measure renal plasma flow.The PAH clearance ln a normal adult lc about 625 mV minute. Thats a measure of effective renal plasma flow ERPF.PAH is only 90 excreted in the urine in a single passage through the kidney, i.e., its extraction ratio is 0.9 90. 