| Project/Area Number |
05454606
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
環境影響評価(含放射線生物学)
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| Research Institution | Asahikawa Medical College |
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Principal Investigator |
KAMIGUCHI Yujiroh Asahikawa Medical College, Medical Dept, Professor, 医学部, 教授 (60091568)
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| Co-Investigator(Kenkyū-buntansha) |
WATANABE Seiji Asahikawa Medical College, Medical Dept, Assistant, 医学部, 教務職員 (10241449)
TATENO Hiroyuki Asahikawa Medical College, Medical Dept, Associate professor, 医学部, 助教授 (80163492)
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| Project Period (FY) |
1993 – 1994
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| Project Status |
Completed (Fiscal Year 1994)
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| Budget Amount *help |
¥5,200,000 (Direct Cost: ¥5,200,000)
Fiscal Year 1994: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 1993: ¥4,100,000 (Direct Cost: ¥4,100,000)
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| Keywords | Human sperm chromosomes / ^<252>Cf neutrons / ^<60>Co gamma-rays / Chromosome aberrations / Frozen hamster oocytes / Cryopreservation of semen / ヒト精子 / 中性子 / γ線 / 精子凍結保存 / 中性子線 |
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| Research Abstract |
Effects of ^<60>Co gamma-rays and ^<252>Cf neutrons on human sperm chromosomes were studies using our interspecific in vitro fertilization system with golden hamster oocytes to estimate relative biological effectiveness (RBE) of neutrons. The RBEs were estimated to be 1.7 and 2.0 with two indices, i.e., the frequency of chromosomally abnormal spermatozoa and the number of structural chromosome aberrations per spermatozoon. These values were considerably lower than those obtained by previous investigators in human lymphocytes (10-80), mouse spermatogonia (20-25) and early embryos (4.7-7.4).
An attempt was made to apply cryopreserved golden hamster oocytes to cytogenetic study of irradiated human spermatozo. There was no significant difference in the frequency of radiation-induced sperm chromosome aberrations between the two assay systems using frozen-thawed oocytes and fresh oocytes, indicating that freezing of the oocytes does not affect the aberration frequency. Cryopreserved hamster o
… More
ocytes are useful to carry out spermchromosome study more conveniently and efficiently.
We also tried to use cryopreserved human spermatozoa in this study. The irradiated semen samples were frozen with a simplified method, thawed at different intervals after cryopreservation, and processed for chromosome analysis. No increase of chromosome aberrations was found at any intervals, indicating that cryopreservation has no effects on radiation-induced DNA damage in spermatozoa. This method is useful for repeated use of subdivided frozen samples and transportation of sample for later cytogenetical use.
To obtain background data for genetic risk assessment of radiation, spontaneous incidence of chromosome aberrations in human spermatozoa was estimated with semen samples from 51 healthy Japanese men. The frequency of chromosmally abnormal spermatozoa was 15.5(]SY.+-。[)4.2% on an average. There was no correlation between aberration frequency and age of donors. The habit of cigarette smoking was also unrelated. Less
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