A substance (Y)is found in the plasma at a concentration of 2 mg/dL.A 24-hour urine collection is performed to determine the renal clearance of Y.The following data are obtained: Urine volume: 1.44 L Urine [Y]: 500 mg/L What is the renal clearance rate of Y?
A healthy 25-year-old woman donates a kidney to her identical twin,who has chronic renal failure.Her serum creatinine concentration before removal of the kidney is 1.0 mg/dL.After removal of her kidney,her serum creatinine concentration increases to 2.0 mg/dL.One month later her serum creatinine concentration has decreased to 1.5 mg/dL.Which of the following accounts for the fact that her serum creatinine concentration fell from 2.0 to 1.5 mg/dL?
A)Decreased production of creatinine by skeletal muscle B)Enhanced secretion of creatinine by the proximal tubule C)Increase in the GFR of each of the remaining nephrons D)Expansion of the extracellular fluid (ECF)volume
A 56-year-old man was admitted to the hospital with a myocardial infarction.At admission,his serum creatinine level was 1.2 mg/dL,and his creatinine clearance rate was 100 mL/minute.Over the next 3 days,he had several periods of hypotension,and his serum creatinine level increased to 3.6 mg/dL.Assuming that he is in steady-state balance for creatinine level (i.e.,amount excreted = amounted produced),what is his predicted creatinine clearance rate?