The cut-all microtome has been known to be a useful method to reveal natural structure of bone marrow. Using “cut-all microtome”, acute bone marrow degeneration and early regeneration process after local
60Co irradiation to rat bone marrow were studied histologically.
The results were as follows:
1) The cut-all microtome method using Epon embedding method was superior to others as was reported previously. This method makes it possible to observe bone marrow in the natural state, especially to observe sinusoidal and stromal changes.
2) After
60Co irradiation of 500 and 1000 r to rat bone marrow, degeneration and disappearance of hematopoietic elements of the erythropoietic and granulopoietic series were noted within three days. In the hematopoietic elements of the megakaryocytic series, after
60Co irradiation of 500 r, only mild changes were found, but after
60Co irradiation of 1004r, significant changes noted.
3) In addition to the above changes, sinusoidal and stromal reaction was noted. Hematopoietic depression and regeneration were found to be correlated with the disap-pearance and regeneration of the sinusoidal microcirculation.
4) Against the previous reports, in the non-irradiated bone marrow, mild degeneration of sinusoid was noted. In this study, associated with the degeneration of sinusoid -dilatation of the sinusoid and exudation-, disappearance of hematopoietic cells was noted. The etiology of the above fact was not known at present.
View full abstract