RABBIT BONE-MARROW AFTER ADMINISTRATION OF SAPONIN - ELECTRON-MICROSCOPIC STUDY
- 1 January 1978
- journal article
- research article
- Vol. 38 (1) , 67-80
Abstract
Saponin rapidly induced injury to the wall of vascular sinuses in rabbit bone marrow so that the barrier between hematopoietic cells and circulation became defective. This change was followed by hypocellularity, necrosis and fibrosis. Adult male rabbits received saponin i.v. (2 mg/kg body wt) every 4 days for periods of up to 4 wk. The animals were killed at varied times. In untreated animals, much of the sinus wall consisted only of endothelium. Within 2 h after administration of saponin the endothelium was damaged and hematopoietic cells, mostly reticulocytes and normoblasts, entered the circulation. Some sinuses hemorrhaged into the hematopoietic compartment. At 4 h, sinuses were markedly dilated and hemorrhage was extensive. By 3 days, extravasated erythrocytes, which were tending to aggregate, were unevenly distributed in the extravascular space of marrow. Damaged hematopoietic cells were dispersed among them. Regenerating blood vessels were noted and a few clusters of hematopoietic cells occurred in association with fibroblasts. At 1 wk, a large portion of the marrow was either necrotic or contained large-scale diffuse or focal hemorrhage. Fibrotic areas often surrounded the arteries. After 2-4 wk, myelofibrosis became pronounced. The fibrotic tissue was well vascularized and contained small clusters of hematopoietic cells and a few fat cells. Macrophages were abundant and tended to fuse, forming multinucleated giant cells surrounding pockets of degenerated fat cells.This publication has 5 references indexed in Scilit:
- The hematopoietic microenvironment of the bone marrow: An ultrastructural study of the stroma in ratsThe Anatomical Record, 1976
- Regeneration of Locally Irradiated Bone Marrow. II. Induction of Regeneration in Permanently Aplastic Medullary CavitiesBlood, 1968
- TRANSFORMATION OF MONOCYTES IN TISSUE CULTURE INTO MACROPHAGES, EPITHELIOID CELLS, AND MULTINUCLEATED GIANT CELLSThe Journal of cell biology, 1966
- REGENERATION OF LOCALLY IRRADIATED BONE MARROW .I. DOSE DEPENDENT LONG-TERM CHANGES IN RAT WITH PARTICULAR EMPHASIS UPON VASCULAR AND STROMAL REACTION1966
- The structure of bone marrow. Functional interrelationships of vascular and hematopoietic compartments in experimental hemolytic anemia: An electron microscopic studyJournal of Morphology, 1965