Biliverdin reductase A activity

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Heme degrades into biliverdin, which is enzymatically (with biliverdin reductase A [BVRA] and energy source NADPH) reduced to bilirubin. Bilirubin is then conjugated and finally excreted to bile. However, in certain circumstances, biliverdin is also converted to biliverdin conjugates, which accumulate in the liver and cause a characteristic green colour (which, together with blood, typically looks black). TCDD is known to cause this in line B rats by increasing heme degradation, but other mechanisms may be involved as well. It is also possible that bilirubin conjugates oxidise into biliverdin conjugates, but there is little evidence about that. To make things more complicated, BVRA may be inhibited by high concentrations of its substrates, namely biliverdin, and possibly by bilirubin. Conjugating enzymes are needed to produce conjugates, but these enzymes are not likely to change significantly in the studies, so they can be treated like constants rather than variables. The original graph: [1]

TODO: {{#todo:Lisää alkuperäinen yksilökohtainen data (uskallatko?). Voisin sen jälkeen kysyä Roger Cooken ja Patrycjan mielipidettä. Tämä on minusta Bayes-päättelyongelma, johon heillä voi olla näkemystä. |Marjo Niittynen|Intarese}}

About measuring biliverdin reductase A R↻ .