Polyfunctional radiosensitizers-v. sensitization of hypoxic chinese hamster cells, V. 79-753B, in vitro by a series of bifunctional nitroxyl compounds

Journal Article · Sat May 01 04:00:00 EDT 1982 · Radiat. Res.; (United States)

DOI:https://doi.org/10.2307/3575705· OSTI ID:5174312

Millar, B C; Jenkins, T C; Fielden, E M

A homologous series of uncharged nitroxyl biradicals have been examined as hyposic cell sensitizers. In the series piperidinic nitroxyl moieties were separated by alkane-dicarboxamide bridging groups containing an increasing number (0 - 7) of methylene groups. In each instance sensitization was characterized by changes in both extrapolation number (n) and the slope of the hypoxic cell survival curve. Increasing the cell-drug contact time from 1 to 3 hr produced an increase in the slope of the survival curve. This was not always associated with a further decrease in n. The present data support the hypothesis that lack of interaction between the radical centers in these and other bifunctional nitroxyls is important for events leading to shoulder modification. The degree of interaction between the radical moieties was assessed from their ESR spectra in solution. In addition, comparison has been made between charged and uncharged forms of a bifunctional nitroxyl compound. In this instance a 3-hr cell-drug contact time in the presence of the uncharge compound resulted in an increase in both slope and n, whereas there was no change in n when cells were irradiated in the presence of the charged compound. When cells which had been preexposed for 3 hr to a biradical, RSU-4072, were irradiated in the presence of a mixture of the biradical and the monoradical TMPN, the survival parameters were characteristic of those seen for TMPN alone. The implications of these results are discussed.

• Research Organization: Inst. of Cancer Research, Sutton, England
• OSTI ID: 5174312
• Journal Information: Radiat. Res.; (United States), Journal Name: Radiat. Res.; (United States) Vol. 90:2; ISSN RAREA
• Country of Publication: United States
• Language: English

Related Subjects

560121* -- Radiation Effects on Cells-- External Source-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMINES
ANIMAL CELLS
ANIMALS
AZINES
CHEMISTRY
CONNECTIVE TISSUE CELLS
DRUGS
ELECTRON SPECTRA
ELECTRON SPIN RESONANCE
FIBROBLASTS
HAMSTERS
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
IN VITRO
IONIZING RADIATIONS
MAGNETIC RESONANCE
MAMMALS
NITROXYL RADICALS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PHYSICAL CHEMISTRY
PIPERIDINES
PYRIDINES
RADIATIONS
RADICALS
RADIOSENSITIVITY EFFECTS
RADIOSENSITIZERS
RESONANCE
RODENTS
SOLUBILITY
SOMATIC CELLS
SPECTRA
SURVIVAL CURVES
VERTEBRATES