Effects of X-radiation on multiplication and nucleic acid synthesis in cultures of L-strain mouse cells

Journal Article · Sat Aug 01 04:00:00 EDT 1959 · Experimental Cell Research

DOI:https://doi.org/10.1016/0014-4827(59)90296-4· OSTI ID:4207854

Whitfield, J. F.; Rixon, R. H.

Dilution of cultures of strain-L mouse cells growing in suspension resulted in an immediate cessation of multiplication but did not immediately affect DNA synthegis. During the period of multiplication arrest, DNA per cell reached the double (premitotic) level and DNA synthesis stopped until the cell content of DNA was reduced by the resumption of cell division. This showed that inhibition of division alone may result in inhibition of DNA synthesis when the cell content of DNA reaches the premitotic level. Cell multiplication was twice as sensitive to irradiation as DNA and RNA synthesis. DNA synthesis was slightly less sensitive than RNA synthesis to doses between 0 and 600 r but slightly more sensitive between 600 and 2000 r. A dose of 4000 r permanently stopped cell division but only temporarily inhibited DNA synthesis which resumed only to stop again when the cell content of DNA reached the double (premitotic) level. A dose of 1000 r did not cause an initial lag in DNA synthesis but reduced total DNA synthesis. Reduced DNA synthesis was accompanied by a high concentration of DNA in the cells. It is concluded that DNA synthesis is relatively insensitive to X- rays. The principal effect of radiation is inhibition, or slowing, of cell division. In the absence of cell division DNA synthesis proceeds until the content per cell is doubled and then stops. At very high doses (4000 r), immediate, but temporary, inhibition occurs in addition to later inhibition by attainment of the double or premitotic DNA content per cell.

• Research Organization: Atomic Energy of Canada Ltd., Chalk River, Ont.
• Sponsoring Organization: USDOE
• NSA Number: NSA-13-021867
• OSTI ID: 4207854
• Journal Information: Experimental Cell Research, Journal Name: Experimental Cell Research Journal Issue: 1 Vol. 18; ISSN 0014-4827
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ANIMAL CELLS
BIOCHEMISTRY
BIOLOGY AND MEDICINE
DNA
MITOSIS
NUCLEIC ACIDS
QUANTITY RATIO
RADIATION DOSES
RADIATION EFFECTS
RADIOSENSITIVITY
RIBONUCLEIC ACID
SUSPENSIONS
VARIATIONS
X RADIATION