Influence of misonidazole on the radiation response of murine tumors of different size: possible artifacts caused by pentobarbital sodium anesthesia

Journal Article · Mon Jun 01 04:00:00 EDT 1981 · Int. J. Radiat. Oncol., Biol. Phys.; (United States)

DOI:https://doi.org/10.1016/0360-3016(81)90469-7· OSTI ID:6340336

Wondergem, J; Haveman, J; van der Schueren, E; van den Hoeven, H; Breur, K

The radiosensitivity of a transplantable murine adenocarcinoma decreased with increasing tumor volume. In unanesthetized mice this phenomenon (based on the effect of the hypoxic cell sensitizer misonidazole), in the range of volumes studied, can largely be explained by the appearance of hypoxic cells in the tumor during growth. The use of pentobarbital sodium during irradiation is confiremd to be a disturbing factor, as it may increase the hypoxic cell fraction in the tumors. No evidence was found for a direct radiochemical protection because of pentobarbital sodium. The radioprotective effect of the anesthetic could only be demonstrated in conditions where there is already a fraction of hypoxic cells; no influence of the anesthesia was found in small tumors in which the fraction of hypoxic cells was relatively small. This may account for the previously conflicting data on the influence of pentobarbital sodium anesthesia. The vascularization of larger tumors is apparently inferior to smaller tumors and this has important repercussions in the case of anesthesia. Changes in blood flow induced by pentobarbital sodium in larger tumors cause an insufficient oxygenation and hence acute hypoxia.

• Research Organization: Univ. of Amsterdam, Netherlands
• OSTI ID: 6340336
• Journal Information: Int. J. Radiat. Oncol., Biol. Phys.; (United States), Journal Name: Int. J. Radiat. Oncol., Biol. Phys.; (United States) Vol. 7:6; ISSN IOBPD
• Country of Publication: United States
• Language: English

Related Subjects

550603 -- Medicine-- External Radiation in Therapy-- (1980-)
560152* -- Radiation Effects on Animals-- Animals
62 RADIOLOGY AND NUCLEAR MEDICINE
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANESTHETICS
ANIMAL CELLS
ANIMALS
ANOXIA
ANTINEOPLASTIC DRUGS
AZINES
AZOLES
BARBITURATES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BLOOD FLOW
CARCINOMAS
CELL PROLIFERATION
CENTRAL NERVOUS SYSTEM DEPRESSANTS
DISEASES
DOSES
DRUGS
ELECTROMAGNETIC RADIATION
HETEROCYCLIC COMPOUNDS
HYPNOTICS AND SEDATIVES
IMIDAZOLES
IONIZING RADIATIONS
MAMMALS
MICE
MISONIDAZOLE
NEMBUTAL
NEOPLASMS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PYRIMIDINES
RADIATION DOSES
RADIATION EFFECTS
RADIATIONS
RADIOPROTECTIVE SUBSTANCES
RADIOSENSITIVITY
RADIOSENSITIVITY EFFECTS
RADIOSENSITIZERS
RODENTS
TUMOR CELLS
VERTEBRATES
VOLUME
X RADIATION