The effects of heavy gamma irradiation upon pituitary glands transplanted into hypophysectomized tadpoles of Bufo boreas
✍ Scribed by Allen, Bennet M.
- Publisher
- John Wiley and Sons
- Year
- 1957
- Tongue
- English
- Weight
- 769 KB
- Volume
- 136
- Category
- Article
- ISSN
- 0022-104X
No coin nor oath required. For personal study only.
✦ Synopsis
We have shown (Allen and Bachman, '56) that irradiation of recently metamorphosed Bufo boreas halophLilzcs up to a dosage level of 30,000r did not modify the capacity of their transplanted pituitary glands to secrete thyrotrophic hormone during the 20 day period of the experiment. When transplanted into young tadpoles they induced as much thyroid stimulation as did unirradiated transplants. The growth of the hind-limbs and the shedding of the cuticular larval teeth served as a biological measure of the induced thyroid secretion. Irradiation with higher dosages diminished the activity of the pituitary transplants as evidenced by lessened effect upon these structures of the tadpole hosts.
In order to carry on the work upon a scale large enough to give dependable quantitative results we made transplants into normal hosts so chosen that the experiment was concluded in 20 days, before the host pituitary gland developed to the point of functional activity. While this procedure enabled us to show definite development of the hind-limbs and loss of cuticular teeth it was highly desirable to extend the experiment for a much longer time to virtual completion of metamorphosis. 'This article is based on work performed under Contract No. AT-04-1-GEN-12 between the Atomic Energy Commission and the University of California at Lo8 Angeles.