Comparison of the Effects of Visible, Ultraviolet, and X-Radiation on Rat Thymocytes

Journal Article · Wed Apr 01 04:00:00 EST 1964 · Canadian Journal of Biochemistry

DOI:https://doi.org/10.1139/o64-062· OSTI ID:4050730

Myers, D. K.; DeWolfe-Slade, Donna

Ultraviolet and X-irradiation produce many of the same effects on rat thymocytes in vitro. Exposure of the cells to low doses results in a latent lethal effect, which requires incubation at 37 °C for its expression, and in an apparent increase in the rate at which deoxyribonucleoprotein from the cells dissolves to form a gel in 2 M NaCl. As the doses are increased, a decrease in the viscosity of the deoxyribonucleoprotein gel, an immediate "death" and swelling of the cells, and an immediate destruction of nucleotide bases become evident. For either radiation, doses which do not appear to have any immediate effect on the intact cell lead to loss of soluble materials (potassium ion, ribonucleotides) from the cells after incubation at 37 °C for several hours. The amount of ultraviolet energy required to produce most of the above effects is nearly 1000 times greater than the amount of X-ray energy required to produce the same effect.Three differences between the effects of ultraviolet and X-irradiation were observed: Ultraviolet light was relatively inefficient in breaking down the long deoxyribonucleoprotein chains but appeared to destroy hydrogen-bonding in the native nucleic acid structure at the same time as it destroyed the nucleotide basis. Moreover, the lethal effects of low doses of ultraviolet light on thymus cells require a longer time to develop than do the effects of X-irradiation.Thymocytes can also be killed by high intensities of visible light, particularly in the presence of photoreducible dyes. Finally, however, visible light produces little or no latent damage to the cells, nor was any evidence of nucleic acid damage observed.

• Research Organization: Atomic Energy of Canada Ltd., Chalk River, Ont.
• Sponsoring Organization: USDOE
• NSA Number: NSA-18-017505
• OSTI ID: 4050730
• Journal Information: Canadian Journal of Biochemistry, Journal Name: Canadian Journal of Biochemistry Journal Issue: 4 Vol. 42; ISSN 0008-4018
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ANIMAL CELLS
BIOCHEMISTRY
BIOLOGY AND MEDICINE
CHEMICAL REACTIONS
COLLOIDS
CYTOLOGY
DECOMPOSITION
DNA
DYES
EFFICIENCY
ENERGY LEVELS
IONS
LETHAL DOSE
LIGHT
NUCLEIC ACIDS
PHOTOSYNTHESIS
POTASSIUM
PROTEINS
RADIATION DOSES
RADIATION EFFECTS
RADIATION INJURIES
RATS
REACTION KINETICS
REDUCTION
RIBONUCLEIC ACID
SENSITIVITY
SODIUM CHLORIDES
SOLUBILITY
SOLUTIONS
SURVIVAL TIME
TEMPERATURE
THYMOCYTES
THYMUS
TISSUES
ULTRAVIOLET RADIATION
VARIATIONS
VISCOSITY
X RADIATION