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What is Substance used to measure renal perfusion:March 2007 and explain in detail?
Ans. B: PAHPara-Aminohippurate (PAH) is a substance used in the measurement of renal blood flow.It is useful in this measurement because it is primarily secreted by the renal tubules; only 20% is filtered by the glomerulus. The renal extraction ratio of PAH is a normal individual is approximately 0.92.