Detection of Heme Oxygenase 1 and 2 Proteins and Bilirubin Formation

Abstract It is possible to detect changes in the level of expression of the two isozymes of heme oxygenase (HO). The sequence differences allow the production of isozyme‐specific antibodies that can be used in immunoblot analysis. Total HO activity in tissue microsomal fractions or extracts of bacteria transformed with an HO gene can be measured as described in this unit using a coupled assay employing biliverdin reductase, which converts the biliverdin product to bilirubin. Bilirubin is then quantified with a scanning spectrophotometer.