Accelerated Induction of Neoplasms in Mouse Kidneys X-irradiated (690 Rad) While Undergoing Compensatory Hyperplasia

Résumé du livre

Groups of young adult mice were subjected to several different treatments: (a) 690 rad wholebody X-irradiation; (b) unilateral nephrectomy and no irradiation; (c) 690 rad irradiation followed by unilateral nephrectomy 1 hour later; (d) unilateral nephrectomy followed by 690 rad irradiation 3 hours later; and (e) unilateral nephrectomy, 690 rad 3 hours later. The mice were examined 1 year or 18 months later for kidney neoplasms. The group nephrectomized and irradiated 3 hours later showed a high incidence (10 out of 19) of kidney adenomas, as compared with none in the mice irradiated only, or nephrectomized only. In addition, a high incidence (11 out of 15) of tubular and Bowman's capsule proliferations was observed in the mice subjected to irradiation first and nephrectomy 1 hour later. Since the accelerated induction of kidney neoplasms observed, occurred under conditions which inhibit mitotic activity and compensatory hypertrophy in the mouse kidney, it is proposed that the development of these renal neoplasms is the consequence of a prolonged imbalance between the stimulus to hyperplasia on the one hand, and the capacity for hyperplasia in radiation-altered kidney cells on the other. (Author).