Figure 4: Sections of specimen stained for in situ hybridization (TNF-alpha mRNA); stainings with antisense (a) and sense (b) probes. The specimen was from the 3w group, experimental side. TNF-alpha mRNA reactions are observable in the endothelial part of a large vein. Arrows point at the occurrence of reactive (a) and non-reactive (b) endothelium of the large vein. Bar=25 μm.