Abstract
The photodynamic effect of protoporphyrin on red blood cells of patients with erythropoietic protoporphyria and on sensitized normal erythrocytes leads primarily to increased passive cation permeability of the membrane. This increased permeability appeared to be caused by photo-oxidation of a cellular target, localized in the red cell membrane. Both unsaturated fatty acids and sulfhydryl, methionyl, histidyl, tyrosyl and tryptophan residues in membrane proteins appeared to be sensitive to protoporphyrin-induced photo-oxidation. It was shown that the increased cation permeability can not be attributed to peroxidation of unsaturated fatty acids in the membrane. Therefore the observed damage of the permeability barrier is presumably caused by photo-oxidation of amino acid residues in membrane proteins. The experimental results are discussed in relation to data in recent literature, concerning the significance of amino acid residues in the maintenance of functional and structural integrity of cellular membranes.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
