Abstract
Purpose & Methods :In order to examine the enhanced effect of nitric oxide (NO) for the induction of polyethyleneglycol (PEG) -liposome containing adriamycin (ADM) into tumor, NO-producing substance (L-arginine), NO scavenger (PTIO) and NOS inhibitor (L-NAME) were administered into subcutaneous tumor model of mouse.
Results : The percentage of injected dose of [3H] labeled PEG-liposome was highest in the liver, next highest in the blood and then in the spleen. Levels were low and approximately equal in the kidney, heart and lung. For each tissue, no significant differences were recognized in the percentages of injected dose in each group. The percentages of injected dose/g tumor after administration of [3H] labeled PEG-liposome in tumor showed that a significantly higher value was found in the L-arginine group than in controls, and in the PTIO group, the value was significantly lower. No significant difference was noted between the L-NAME group and the control group. The tumor doubling time in the L-arginine group was similar to the control, but the doubling times were significantly longer in the Lip-ADM group and the Lip-ADM with L -arginine group. That of the Lip-ADM with L-arginine group was also significantly longer than that of the Lip-ADM group.
Conclusion : These results revealed that NO could enhance tumor vascular permeability and the accumulation of PEG-liposome containing ADM, with anti-tumor effect.
