How is prostatic ACP calculated?

• A. Total ACP minus ACP after tartrate inhibition
• B. Tartrate inhibited ACP minus total ACP
• C. Total ACP divided by ACP after tartrate inhibition
• D. Prostate ACP equals RBC ACP

Answer: (A)

This item tests how the prostatic fraction of acid phosphatase is separated from other tissue sources using tartrate inhibition. Many tissues produce acid phosphatase, but the prostatic form is resistant to tartrate inhibition, while non-prostatic forms are inhibited. By measuring the total acid phosphatase activity and then measuring how much of that activity is inhibited by tartrate, you can isolate the prostatic component. The prostatic ACP equals the activity that remains after tartrate inhibition, which is obtained by subtracting the tartrate-inhibited (non-prostatic) activity from the total activity. In other words, prostatic ACP = total ACP − tartrate-inhibited ACP.