Test Catalog

Test ID: METR1    
Cytochrome b5 Reductase Enzyme Activity, Blood

Method Description Describes how the test is performed and provides a method-specific reference

Cytochrome b5 reductase (methemoglobin reductase) catalyzes the 1,4-Dihydronicotinamide adenine dinucleotide (NADH)-linked reduction of several substrates, including ferricyanide. The activity at 37 degrees C is measured spectrophotometrically by measuring the oxidation of NADH to NAD+ at 340 nm on an automated chemistry analyzer.(Fairbanks VF, Klee GG: Biochemical aspects of hematology. In: Burtis CA, Ashwood ER, eds. Tietz Textbook of Clinical Chemistry. 3rd ed. WB Saunders Company. 1999:1647-1648; van Solinge WW, van Wijk: Enzymes of the red blood cell. In: Rifai N, Horvath AR, Wittwer CT: eds. Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 6th ed. Elsevier; 2018:chap 30)

PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) Performed Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Performed weekly

Report Available The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

1 to 6 days

Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

7 days

Performing Laboratory Location Indicates the location of the laboratory that performs the test