AGE-DEPENDENT CHANGES IN THE METABOLISM OF THYMIDINE-H-3 AND URIDINE-H-3 IN YOUNG-RATS

  • 1 January 1979
    • journal article
    • research article
    • Vol. 43  (2) , 105-115
Abstract
The metabolism of s.c. injected 3H-thymidine and 3H-uridine was studied in 5-, 15- and 30-day old rats, and some age-dependent differences were found. The total availability of 3H-uridine decreased when the rats became older. In the case of 3H-thymidine, however, there were only minor differences in the total availability. The catabolism of both 3H-thymidine and 3H-uridine, as measured by the appearance of 3H-water, was more efficient when the rats became older. In the case of 3H-thymidine, however, the increased catabolic capacity seemed to be compensated by a decreased proliferative growth so the total availability should be constant. The amount of intermediate catabolic products in the blood was much larger after an injection of 3H-uridine than after 3H-thymidine.