Pharmacokinetics and radiosensitizing effect of PR-350.
OBJECTIVE
The in vivo pharmacokinetics and sensitizing effects of PR-350, a newly developed, highly water-soluble radiosensitizer were examined.


METHODS
C3H/HeJ mice bearing SCC-VII tumor cells were used in the experiments. Results were compared with those of PR-28 and SR-2508.


RESULTS
The intratumoral concentration of PR-350 reached the maximum value of 77.7 mg/kg 20 min after intravenous injection. The concentration in the brain was below the detection limit. The enhancement ratios of PR-350 calculated using the growth delay method were 0.9 for PR-350 at 50 mg/kg and 1.4 for PR-350 at 100 mg/kg, compared with 1.4 for SR-2508 at 100 mg/kg and 1.0 for PR-28 at 100 mg/kg.


CONCLUSIONS
PR-350 and SR-2508 revealed similar sensitizing effects. The side effects of PR-350 are expected to be equal to or less than those of SR-2508. PR-350 seems to be a promising radiosensitizer.
Hirokawa
K
K
Department of Radiology, Osaka City University Medical School, Osaka, Japan.
Nakajima
T
T
Tsumura
M
M
Nishita
T
T
Yamada
R
R
Onoyama
Y
Y
D000818:Animals; D001921:Brain / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000532:radiotherapy*; D004307:Dose-Response Relationship, Radiation; D007093:Imidazoles / Q000493:pharmacokinetics* / Q000627:therapeutic use; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D009368:Neoplasm Transplantation; D011838:Radiation-Sensitizing Agents / Q000493:pharmacokinetics* / Q000627:therapeutic use
D007093:Imidazoles; D011838:Radiation-Sensitizing Agents; C106738:doranidazole