Intestinal microflora as potential modifiers of sensitizer activity in vivo.
Treatment of mice (some bearing Lewis Lung tumors), with penicillin (PEN) at 500 mg/l drinking water for one week prior to treatment with misonidazole (MIS), resulted in: the elimination of their anaerobic cecal flora; a decrease in MIS-induced neurotoxicity; an increase in pharmacological exposure to MIS; a decrease in MIS chemopotentiation; a probable increase in MIS radiosensitization; an increase in MIS induced hypothermia. Assuming no chemical interaction between PEN and MIS, these observations indicate that the intestinal microflora can influence the activity of MIS in vivo. Therefore their influence should be considered in all sensitizer-related studies in vivo. The observed reduction in the neurotoxic but not the radiosensitizing potential of MIS following PEN treatment indicates a therapeutic benefit.
D000818:Animals; D001419:Bacteria / Q000378:metabolism*; D001831:Body Temperature / Q000187:drug effects; D003131:Combined Modality Therapy; D004357:Drug Synergism; D005260:Female; D007422:Intestines / Q000382:microbiology*; D008175:Lung Neoplasms / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy; D008558:Melphalan / Q000627:therapeutic use; D051379:Mice; D008920:Misonidazole / Q000494:pharmacology* / Q000627:therapeutic use; D009593:Nitroimidazoles / Q000494:pharmacology*; D010406:Penicillins / Q000494:pharmacology; D011838:Radiation-Sensitizing Agents / Q000494:pharmacology* / Q000627:therapeutic use
D009593:Nitroimidazoles; D010406:Penicillins; D011838:Radiation-Sensitizing Agents; D008920:Misonidazole; D008558:Melphalan