Relationship between hyperthermic cell killing and protein denaturation by alcohols

Journal Article · Sat Aug 01 00:00:00 EDT 1981 · Radiat. Res.; (United States)

DOI:https://doi.org/10.2307/3575584· OSTI ID:6191764

Massicotte-Nolan, P; Glofcheski, D J; Kruuv, J; Lepock, J R

The monohydric alcohols methanol, ethanol, 2-propanol, and tert.-butanol dramatically sensitize V79 Chinese hamster lung cells to hyperthermia. for concentrations less than 3% alcohol by weignt, the rate of cell inactivation (k) appears to vary exponentially as a function of alcohol concentration. The degree of sensitization increases with increasing chain length, and for a constant concentration the ratio of the k's is 1:1.3:1.8:3.1 for methanol, ethanol, 2-propanol, and t-butanol, respectively. Mono-, di-, and trihydric alcohols have similar effects upon the rate of protein denaturation. Membrane lipid fluidity of V79 cells was determined from 23 to 63/sup 0/C by measuring the rotational correlation time of the spin label 2,2-dimethyl-5-dodecyl-5-methyloxazolidine-N-oxide (2N14). A straight line was found for the Arrhenius plot of tau/sub c/, with an activation energy of 4.82 +- 0.07 kcal/mole. From the Arrhenius plot of the rate of cell killing from 42.0 to 46.8/sup 0/C, the enthalpy (..delta..H) and entropy (..delta..S) of activation were found to be 146 +- 9 kcal/mole and 388 cal/mole K, respectively. These values are consistent with protein denaturation (or possibly the denaturation of some other macromolecule) being the rate-limiting step in hyperthermic cell killing.

• Research Organization: Univ. of Waterloo, Ontario
• OSTI ID: 6191764
• Journal Information: Radiat. Res.; (United States), Vol. 87:2
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
62 RADIOLOGY AND NUCLEAR MEDICINE
BUTANOLS
BIOLOGICAL EFFECTS
CELL MEMBRANES
ELECTRON SPIN RESONANCE
ETHANOL
HYPERTHERMIA
METHANOL
PROPANOLS
ARRHENIUS EQUATION
CELL KILLING
HAMSTERS
PROTEIN DENATURATION
RESPIRATORY TRACT CELLS
SURVIVAL CURVES
ALCOHOLS
ANIMAL CELLS
ANIMALS
BODY TEMPERATURE
CELL CONSTITUENTS
EQUATIONS
HYDROXY COMPOUNDS
MAGNETIC RESONANCE
MAMMALS
MEMBRANES
ORGANIC COMPOUNDS
RESONANCE
RODENTS
VERTEBRATES
550300* - Cytology
550603 - Medicine- External Radiation in Therapy- (1980-)