Horseradish peroxidase as a permeability marker in injured rat caudal and iliac arteries.
The permeability to Horseradish Peroxidase (HRP) of the rat caudal artery at the level of spontaneous lesions was evaluated by electron microscopy and compared with that of lesions experimentally induced by pinching or internal scraping of the caudal and iliac arteries. No HRP reaction product is observed in the extracellular space of the arterial wall when (i) the internal elastic lamina (IEL) and the endothelium are absent, (ii) the IEL is maintained and the endothelium is absent and (iii) the IEL is absent and the endothelium has regenerated. That HRP does enter the arterial wall in cases of gross endothelial damage is shown by its selective retention in damaged smooth muscle cells in such cases. In contrast, HRP reaction product is detected in the subendothelial space when the IEL is maintained and is covered by a regenerating or recently regenerated endothelium. Furthermore, the amount of tracer visualized under the same experimental conditions is greater in the iliac than in the caudal artery. We conclude that the detection of HRP in the subendothelial space of the artery wall requires the presence of regenerating or recently regenerated endothelial cells lying on an intact IEL. It is thus not simply related to endothelial permeability but depends also upon the retention of HRP by extracellular substances. In addition, the quantity of marker retained varies between different sites in the arterial tree.
Elemer
G
G
INSERM U7, Hôpital Necker, Paris, France.
Osborne-Pellegrin
M J
MJ
D000818:Animals; D001158:Arteries / Q000293:injuries* / Q000473:pathology / Q000503:physiopathology; D015415:Biomarkers; D002199:Capillary Permeability / Q000502:physiology*; D002244:Carbon / Q000493:pharmacokinetics; D002463:Cell Membrane Permeability / Q000502:physiology*; D003102:Colloids; D004547:Elastic Tissue / Q000166:cytology / Q000502:physiology / Q000648:ultrastructure; D004730:Endothelium, Vascular / Q000166:cytology / Q000502:physiology / Q000648:ultrastructure; D005455:Fluorescent Antibody Technique; D006735:Horseradish Peroxidase / Q000493:pharmacokinetics*; D007083:Iliac Artery / Q000293:injuries* / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D051381:Rats; D011919:Rats, Inbred Strains
D015415:Biomarkers; D003102:Colloids; D002244:Carbon; D006735:Horseradish Peroxidase