Studies on the radioprotective effect of etiocholanolone

Etiocholanolone, a metabolite of testosterone and dehydroepiandrosterone has been shown in previous experiments to have a stimulatory effect on hematopoietic cells (Vollmer, Gordon, 1941; Rishpon-Meyerstein, Kilbridge et al., 1968). We wanted to explore its possible radioprotective effect alone and in combination with homologous bone marrow transplantation. One-hundred forty male mice of an inbred strain (C3H/St) were divided into four groups of thirty-five each and were given total body irradiation of 750 cGy. After X-irradiation, one group was given etiocholanolone alone, the other was given bone marrow alone, a third was given both of these. One group was used as a control and was given no treatment after irradiation. The bone marrow used was obtained from the same inbred strain of mice. The most remarkable hematologic recovery was seen in the group which was given both etiocholanolone and bone marrow. The groups given only etiocholanolone or only bone marrow recovered better than the control group. Overall survival was best for the group receiving both modes of treatment and worst for the control group. Survival for the groups receiving a single mode of treatment lay in between the other two mentioned above.