Evans blue-albumin complex

Fig. 6 NO-dependent vascular permeability of solid tumors (S-180) as quantified by uptake of Evans blue albumin complex in tumor of various sizes in mice. Mice were administered with NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-l-oxyl 3-oxide (PTIO) orally (dose PTIO, 125 mg/kg 1 4 in 8 h). Note that EPR effect is greatly suppressed by PTIO, which is a fraction of NO contributing to EPR effect. Further note that when the tumor size is larger than 0.25 g, the contribution of NO in EPR effect is less pronounced. This implicates the importance of NO at the early stages of tumor growth (see text) (from [42] after modification)...

Figure 1. Accumulation of Evans blue-albumin complex in the tumor tissue. Tumor S-I80 was injected into mice skin. A to D provide a macroscopic picture of the tumor in the skin taken at 0,6, 24 and 72h, respectively, alto- i.v. injection of Evans blue (lOmg/kg).

Figure 2. Clearance of Evans blue-albumin complex from blood plasma and its accumulation in tumor tissue and normal skin in tumor-bearing mice. Quantification of concentration of die Evans blue-albumin complex at different times for plasma ( ), normal skin ( fl ), and tumor ( ).

The characteristics of vascular pathophysiology Usted in Table 1 contribute to the selective, enhanced accumulation and prolonged retention of macro-molecular drugs or lipid particles in tumor tissue (EPR effect). Evans blue dye, which forms complexes with albimiin (67 kDa) or lipiodol (a lipid contrast agent), clearly revealed the presence of the EPR effect in rodent tumors after intravenous injection of Evans blue bound albumin, or after arterial... 

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