In vivo exocytosis of lysosomes by the endothelium of the venous sinuses of bone marrow and liver: Visualization at normal and low body temperature
Article first published online: 3 FEB 2005
Copyright © 1986 Wiley-Liss, Inc.
American Journal of Anatomy
Volume 177, Issue 1, pages 35–41, September 1986
How to Cite
De Bruyn, P. P. H. and Cho, Y. (1986), In vivo exocytosis of lysosomes by the endothelium of the venous sinuses of bone marrow and liver: Visualization at normal and low body temperature. Am. J. Anat., 177: 35–41. doi: 10.1002/aja.1001770105
- Issue published online: 3 FEB 2005
- Article first published online: 3 FEB 2005
- Manuscript Accepted: 4 MAY 1986
- Manuscript Received: 30 DEC 1985
We have visualized the exocytosis of lysosomes into the peripheral circulation by the phagocytic endothelia of the venous sinuses of liver and bone marrow of rats. Perfusion fixation at normal body temperature produced images of the earliest stages of lysosomal exocytosis. After fixation at low body temperatures (7–12°C), advanced stages of this process became evident, showing extrusion of lysosomes and their contents into the circulation. It is postulated that this form of exocytosis has escaped structural detection because of its rapidity and relative infrequency as compared to merocrine secretory exocytosis, and that fixation at low body temperatures arrests or slows down these exocytic events in sufficient measure for ultrastructural visualization. The possibility that this lysosomal exocytosis contributes to the presence of lysosomal enzymes detected in the peripheral blood should be considered. In addition, it is likely that lysosomal degradation products may be discharged by exocytosis into the circulation.