Endothelial diaphragmed fenestrae: in vitro modulation by phorbol myristate acetate
Cultured microvascular endothelial cells isolated from fenestrated capillaries have been shown to express many properties of their in vivo differentiated phenotype, yet they contain very few diaphragmed fenestrae. We show here that treatment of capillary endothelial cells with the tumor promoter, 4..beta..-phorbol, 12-myristate, 13-acetate, induces more than a fivefold increase in the frequency of fenestrae per ..mu..m/sup 2/ of cell surface, as determined from a quantitative evaluation on freeze-fracture replicas. In quick-frozen, deep-etched preparations, the endothelial fenestrae appeared to be bridged by a diaphragm composed of radial fibers interweaving in a central mesh, as previously observed in vivo. These results indicate that diaphragmed fenestrae are inducible structures, and provide an opportunity to study them in vitro.
- Research Organization:
- Univ. of Geneva Medical School, Switzerland
- OSTI ID:
- 5786695
- Journal Information:
- J. Cell Biol.; (United States), Vol. 102
- Country of Publication:
- United States
- Language:
- English
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