|
|
||||||||
Biology of Reproduction, Vol 8, 607-612, Copyright © 1973 by Society for the Study of Reproduction
-Radiation
1 UT-AEC Agricultural Research Laboratory,2 Oak Ridge, Tennessee 37830 Testes of SpragueDawley rats aged either 2 or 12 months were administered 285 rads
of 60Co No significant difference in number of type-A spermatogonia was observed in testes
of nonirradiated rats between the ages of 2 and 16 months. Irradiation reduced spermatogonial numbers to 21 to 25% of control in both age groups, but the postirradiation
interval at which it occurred was differentday 5, 2 months; day 10, 12 months. By
24 days after irradiation, spermatogonial numbers had increased to 55% of control in
2-month testes, but 12-month testes were only at 40% of control. The magnitude of
the difference between young and old did not change at later postirradiation stages.
At 80 days after irradiation, spermatogonial numbers peaked at 90% of control in 2-month
testes and 74% of control in 12-month testes. Percents of control at 120 days postirradiation
were 84 and 70% for 2- and 12-month testes, respectively. These results lead to the
conclusion that irradiation produces a permanent decrement in the stem spermatogonial
population with the magnitude of the decrement being age dependent.
-radiation at 45 rads/min. Irradiated animals along with controls (10 per group)
were killed at postirradiation intervals varying from 5 to 120 days. Irradiation effects
were assayed through testicular weights and counts of type-A spermatogonia in 50 cross
sections of seminiferous tubules at stages 5 to 8 of the spermatogenic cycle.
Revised on October 20, 1972
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |