Enhancement of tumor blood flow and tumoricidal effect of doxorubicin by intraportal epinephrine in experimental liver metastasis.

Laser Doppler capillary perfusion monitoring was performed in 25 Sprague-Dawley rats with solitary intrahepatic implants of Walker carcinosarcomas. Doses of intraportal epinephrine from 1 to 10 micrograms produced an immediate rise in capillary blood flow, reaching peak levels by 16 s. The increased flow lasted an average of 57 s. Because epinephrine selectively increased tumor blood flow, studies were performed to determine if enhancement of the chemotherapeutic effect of doxorubicin could be achieved. Forty-two rats with seven-day hepatic implants were treated sequentially with intraportal epinephrine (10 micrograms) and doxorubicin hydrochloride (10 mg/kg) or doxorubicin alone. After only two courses of chemotherapy, a significant difference in necrosis and cell viability was obtained in those animals treated with epinephrine intraportally prior to doxorubicin infusion. Enhancement of the tumoricidal effect of chemotherapy can be achieved by manipulating the blood flow to developing tumors pharmacologically.