The influence of sodium pentobarbital anesthesia on in vivo photodynamic therapy.

Abstract

Abstract The use of sodium pentobarbital anesthesia 50 jig gm−1 during localized photodynamic therapy (PDT) was examined in C57BL/6 mice transplanted with the pigmented B‐16 melanoma. A 10 mg kg−1 i.p. injection of Photofrin II was administered 24 h prior to light exposure (630 nm, 150 mW, cm−2, 300‐500 J cm−2). Separate groups of mice were utilized to monitor tumour temperature and PDT tumor response. Core tumor temperatures decreased by approx. 10oC following sodium pentobarbital administration. Tumor responses were determined by documenting the percentage of treated animals without tumor recurrences for a period of 50 days following PDT. Superior PDT induced tumor responses were obtained in control (non‐anesthetized) mice following light doses of 400 and 500 J cm−2. The results of this study indicate that sodium pentobarbital can induce a protective effect on B‐16 melanomas treated with PDT.