Influence of nandrolone decanoate on the repopulation of the thymus after total body irradiation of mice.

Abstract It has been repirted that nandrolone decanoate is helpful in overcoming the neutropenic phase following irradiation. In the present study the influence of nandrolone decanoate on the thymus' cellularity after total body irradiation was investigated. In comparison with a placebo-treated group, mice receiving nandrolone decanoate showed a similar pattern of thymus repopulation, but a significantly lower number of thymocytes over the whole period of treatment was found. Nonirradiated mice also had a significantly lower number of thymocytes when treated with nandrolone decanoate. In addition, the number of circulating leukocytes was also evaluated over a period of 1 month after total body irradiation. On 11 of the 21 days investigated, a significantly higher number of leukocytes was found in the nandrolone decanoate-treated group. We conclude that the action of nandrolone decanoate was not clearly distinct from that of testosterone regarding either granulopoiesis or thymic involution.