Effect of continuous gamma-radiation on the stem and differentiating spermatogonia of the adult rat.

Sprague-Dawley rats were irradiated continuously (60Co, gamma) at a dose-rate of either 1 (0.0007 rad/min), 3 or 6 rad/23-h day for monthly intervals of 1 to 6. At one month after irradiation, counts of differentiating spermatogonia (A1 and A4) were reduced to a level that remained essentially unchanged during the succeeding 5 months of irradiation. The magnitude of the irradiation effect was greatest at stage 1 of the spermatogenic cycle where numbers of differentiating spermatogonia were reduced to 50% of control by 1 rad/day and to 30 and 20% of control by 3 and 6 rad/day, respectively. Number of stem spermatogonia was not significantly affected by 1 rad/day (P greater than 0.10). At 3 and 6 rad, however, number of stem cells declined from 80% of control at 1 month to 60 and 40% of control at 6 months, respectively. At a dose-rate of 1 rad/day there was neither a reduction in number of A1 spermatogonia per clone nor significant evidence of necrosis among either stem or differentiating spermatogonia; therefore, a reduction of stem-cell mitotic activity appears to be the principal effect of continuous low-level irradiation on spermatogenesis in the rat.

[1]  M. Fox,et al.  INFLUENCE OF RECOVERY FROM SUBLETHAL DAMAGE ON THE RESPONSE OF CELLS TO PROTRACTED IRRADIATION AT LOW DOSE-RATE. , 1970 .

[2]  W. Dewey,et al.  G2 block in Chinese hamster cells induced by x-irradiation, hyperthermia, cycloheximide, or actinomycin-D. , 1976, Radiation research.

[3]  B. H. Erickson.  Effect of 60Co gamma radiation on the stem and differentiating spermatogonia of the postpuberal rat. , 1976, Radiation research.

[4]  L. Braby,et al.  Division delay after low X-ray doses and treatment with cycloheximide. , 1977, Radiation research.

[5]  E. Oakberg.  Spermatogonial stem‐cell renewal in the mouse , 1971, The Anatomical record.

[6]  E. Miller,et al.  Quantitative histologic analysis of the effect of chronic whole-body irradiation with gamma rays on the spermatogenic elements and the interstitial tissue of the testes of mice. , 1948, Journal of the National Cancer Institute.

[7]  L. Lajtha,et al.  Haemopoietic stem-cell kinetics during continuous irradiation. , 1975, International journal of radiation biology and related studies in physics, chemistry, and medicine.

[8]  R. Warters,et al.  Radionuclide toxicity in cultured mammalian cells. Elucidation of the primary site for radiation-induced division delay. , 1977, Radiation research.

[9]  C. P. Leblond,et al.  DEFINITION OF THE STAGES OF THE CYCLE OF THE SEMINIFEROUS EPITHELIUM IN THE RAT , 1952, Annals of the New York Academy of Sciences.

[10]  C. Huckins.  THE SPERMATOGONIAL STEM CELL POPULATION IN ADULT RATS , 1971, Cell and tissue kinetics.

[11]  D. G. Rooij,et al.  SPERMATOGONIAL STEM CELL RENEWAL IN THE MOUSE: II AFTER CELL LOSS , 1973 .

[12]  B. Kimler,et al.  125I-UDR induced division delay. , 1977, Biophysical Journal.

[13]  J. Little.  Irradiation of primary human amnion cell cultures: effects on DNA synthesis and progression through the cell cycle. , 1970, Radiation research.

[14]  D. D. de Rooij,et al.  Response of stem cells in the mouse testis to fission neutrons of 1 MeV mean energy and 300 kV x rays. Methodology, dose-response studies, relative biological effectiveness. , 1976, Radiation research.

[15]  P. Oftedal,et al.  A theoretical study of mutant yield and cell killing after treatment of heterogeneous cell populations. , 2009, Hereditas.

[16]  E. Oakberg.  Initial depletion and subsequent recovery of spermatogonia of the mouse after 20 r of gamma rays and 100, 300, and 600 r of x-rays. , 1959, Radiation research.

[17]  D. Goodhead,et al.  The relation between induced mutation frequency and cell survival--a theoretical approach and an examination of experimental data for eukaryotes. , 1977, Mutation research.

[18]  C. Huckins.  The spermatogonial stem cell population in adult rats. I. Their morphology, proliferation and maturation , 1971, The Anatomical record.

[19]  E. Humphreys,et al.  Cytogenetic effects of protracted exposures to alpha-particles from plutonium-239 and to gamma-rays from cobalt-60 compared in male mice. , 1976, Mutation research.

[20]  E. Oakberg,et al.  Effect of dose and dose rate on radiation damage to mouse spermatogonia and oocytes as measured by cell survival. , 1961, Journal of cellular and comparative physiology.

[21]  E. A. Jones.  Number of spermatogonia after x-irradiation of the adult rat. , 1960, International journal of radiation biology and related studies in physics, chemistry, and medicine.

[22]  L. Hermo,et al.  Spermatogonial stem cells in the albino rat. , 1975, The American journal of anatomy.