Extracellular talaporfin sodium-induced photosensitization reaction with various albumin animal species on myocardial cells in vitro

It is reported that the albumin has different structure among animal species. We have proposed a new methodology of cardiac ablation using talaporfin sodium-induced photosensitization reaction with short drug-light interval to realize immediate and permanent therapeutic effect by singlet oxygen production mainly in the interstitial space. The photosensitization reaction efficacy with different animal species should be investing to consider the optimal animal therapeutic model to evaluate the therapeutic effect of new cardiac ablation methodology. We studied the cell-killing efficacy of extracellular talaporfin sodium-induced photosensitization reaction using talaporfin sodium on myocardial cells in vitro with different albumin animal species: human, canine, bovine, and porcine serum albumin. We obtained that the albumin concentration tendency on the binding ratio and cell lethality was different among the animal species but there was no correlation between binding ratio and cell lethality. We found that the cell lethality dependence on albumin concentration showed 2 different groups, human-canine and bovine-porcine. We think that the canine might be useful as a therapeutic animal model since the cytotoxicity tendency on albumin concentration was similar with that of human albumin. These cell lethality tendency difference would be suggested to explain by the existence of the diazepam site that talaporfin sodium binds mainly.