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Photochemistry of Porphyrins and Bile Pigments in Homogeneous Solution

  • T. G. Truscott
  • Antony F. McDonagh
  • David A. Lightner
  • C. Lambert
  • M. A. J. Rodgers
  • G. Jori
  • E. Reddi
  • J. D. Spikes
  • Ralph L. Brookfield
  • Bobby Redmond
  • Edward J. Land
  • T. George Truscott
  • Garry R. Buettner
  • Roy Pottier
  • James Kennedy

Abstract

Porphyrins and bile pigment are examples of tetrapyrrolic pigments and this group of pigments are the most widely occurring coloured materials in nature. Porphyrin structures are based on the porphin nucleus with side chains substituted on the various peripheral positions. The basic structures of the porphyrins related to haem biosynthesis and of haematoporphyrin (Hp) and related porphyrins which are of importance in cancer photo-chemotherapy are shown in Figure 1. It was first demonstrated by Meyer-Betz in 1913 that porphyrins are related to photodynamic activity in man and it is now established that the photosensitivity associated with various porphyric diseases is due to the presence of excess porphyrin in the skin. The porphyrins which cause porphyria arise by a disfunction of haem biosynthesis and vary in structure depending on the particular step in the biosynthetic pathway at which the enzymic disfunction occurs. The so-called ‘Hp Derivative’ (HpD) is currently of interest in the photochemotherapy of some tumours. Current views of the nature of the active component of HpD is that it consists of a substantial number of Hp molecules linked via ether bridges with the overall structure that of a folded molecule. It is presumed that such a macromolecule can transfer one Hp or possibly one hydroxyethylvinyldeuteroporphyrin (HVD) entity at a time on interaction with a tumour cell. It is also possible that Hp and HVD are in equilibrium with protoporphyrin (pp) and even deuteroporphyrin (dp)1 in the tumour.

Keywords

Human Serum Albumin Singlet Oxygen Dimethyl Ester Neonatal Jaundice Laser Flash Photolysis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1985

Authors and Affiliations

  • T. G. Truscott
    • 1
  • Antony F. McDonagh
    • 2
  • David A. Lightner
    • 3
  • C. Lambert
    • 4
  • M. A. J. Rodgers
    • 4
  • G. Jori
    • 5
  • E. Reddi
    • 5
  • J. D. Spikes
    • 6
  • Ralph L. Brookfield
    • 7
  • Bobby Redmond
    • 8
  • Edward J. Land
    • 9
  • T. George Truscott
    • 8
  • Garry R. Buettner
    • 10
  • Roy Pottier
    • 11
  • James Kennedy
    • 12
  1. 1.Paisley College Chemistry DepartmentPaisleyScotland, UK
  2. 2.Department of Medicine, Gastroenterology Unit and The Liver CenterUniversity of CaliforniaSan FranciscoUSA
  3. 3.Department of Chemistry and The Cellular and Molecular Biology ProgramUniversity of NevadaRenoUSA
  4. 4.Center for Fast Kinetics Res.Univ. of TexasAustinUSA
  5. 5.Istituto di Biologia AnimaleUniv. degli StudiPadovaItaly
  6. 6.Dept. of BiologyUniv. of UtahSalt Lake CityUSA
  7. 7.Davy Faraday Research LaboratoryThe Royal Institution of Great BritainLondonUK
  8. 8.Paisley CollegePaisleyScotland, UK
  9. 9.Paterson Labs.Christie Hospital and Holt Radium InstituteManchesterEngland, UK
  10. 10.Laboratory of Molecular BiophysicsNational Institute of Environmental Health SciencesResearch Triangle ParkUSA
  11. 11.Dept. of Chem/Chem Eng.Royal Military CollegeKingstonCanada
  12. 12.Ontario Cancer FoundationKingston ClinicKingstonCanada

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