Laser microirradiation of Chinese hamster cells at wavelength 365 nm: effects of psoralen and caffeine

Journal Article · Sun Mar 01 00:00:00 EST 1981 · Radiat. Res.; (United States)

DOI:https://doi.org/10.2307/3575423· OSTI ID:6566673

Cremer, T ^[1]; Peterson, S P; Cremer, C; Berns, M W

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1. Inst. of Anthropology and Human Genetics, Heidelberg, Germany

Cells of a V79 subline of the Chinese hamster were microirradiated at wavelength 365 nm in the presence of the psoralen derivative, trioxsalen. Microirradiation was accomplished by a pulsed argon laser microbeam either in anaphase or in interphase 3 h after mitosis. Inhibition of clonal growth and formation of micronuclei at the first postirradiation mitosis were observed after microirradiation of anaphase chromosomes and of small parts of the interphase nucleus. Microirradiation of the cytoplasm beside the interphase nucleus or between the sets of chromosomes moving apart from each other in anaphase did not produce these effects. Anaphase experiments showed that only the daughter cell which received microirradiated chromatin exhibited an abnormal growth pattern. Most interestingly, shattering of the whole chromosome complement could be induced by microirradiation of small parts of the interphase nucleus and post-treatment with caffeine. Since microirradiation of chromatin in the absence of psoralen was not effective, we consider formation of psoralen photoadducts to nucleic acids in microirradiated chromatin to be the specific cause of the effects. We suggest that DNA photolesions in chromosome segments present in the microirradiated part of the nucleus can induce shattering of all the chromosomes in the microirradiated nucleus. Several possibilities are discussed to explain this unexpected finding.

• OSTI ID: 6566673
• Journal Information: Radiat. Res.; (United States), Vol. 85:3
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CAFFEINE
RADIOSENSITIVITY EFFECTS
CHROMOSOMES
BIOLOGICAL RADIATION EFFECTS
PSORALEN
STRAND BREAKS
RADIOINDUCTION
CELL CULTURES
DNA
HAMSTERS
LASER RADIATION
MITOSIS
ULTRAVIOLET RADIATION
ANALEPTICS
ANIMALS
ANTICOAGULANTS
BIOLOGICAL EFFECTS
CELL DIVISION
CENTRAL NERVOUS SYSTEM AGENTS
COUMARINS
DRUGS
ELECTROMAGNETIC RADIATION
HEMATOLOGIC AGENTS
HETEROCYCLIC COMPOUNDS
MAMMALS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PURINES
RADIATION EFFECTS
RADIATIONS
RODENTS
VERTEBRATES
XANTHINES
560121* - Radiation Effects on Cells- External Source- (-1987)
560111 - Radiation Effects on Biochemicals- In Vitro- (-1987)