Molecular Mechanisms of Phototherapy of Neonatal Jaundice

  • Antony F. McDonagh


The success of phototherapy depends on photochemical transformations of bilirubin within light-exposed tissues. These reactions alter the structure of bilirubin in such a way that the intact molecule or fragments of it can be excreted via the kidney or liver without having to undergo further metabolic modification. So far three photochemical reactions of bilirubin have been shown to occur in vivo, and it is likely that these three together account for most of the effect of light on bilirubin metabolism in jaundiced newborns. The three reactions are photooxidation, configurational isomerization, and structural isomerization. In this presentation I shall discuss briefly some of our evidence for the occurrence of these reactions in vivo and speculate on their relative contributions to the net effect of phototherapy. Since the interpretation of the in vivo studies is very much dependent on knowledge gleaned from in vitro photochemical studies, I shall begin with a discussion of the latter.


Human Serum Albumin Dimethyl Ester Neonatal Jaundice COOH COOH Bile Fistula 
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Copyright information

© Springer Science+Business Media New York 1984

Authors and Affiliations

  • Antony F. McDonagh
    • 1
  1. 1.The Liver Center and Department of MedicineUniversity of CaliforniaSan FranciscoUSA

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