Scanning electron microscopy: arterial endothelial integrity after fixation at physiological pressure

Area of Science:

• Vascular Biology
• Microscopy Techniques

Background:

• The endothelium forms the inner lining of blood vessels, playing a crucial role in vascular health.
• Assessing endothelial integrity is vital for understanding vascular diseases.
• Scanning electron microscopy (SEM) is a powerful tool for visualizing cellular structures.

Purpose of the Study:

• To determine the optimal method for preserving rabbit aorta endothelium for scanning electron microscopy (SEM) analysis.
• To evaluate the impact of fixation methods on the morphological integrity of the endothelium.

Main Methods:

• Normal rabbit aortas were examined using scanning electron microscopy (SEM).
• Endothelial cells were outlined by staining intercellular junctions with silver.
• Aortas were either fixed in situ at physiological pressure or excised and then fixed.

Main Results:

• Fixation in situ at physiological pressure allowed for reliable assessment of endothelial morphological integrity.
• Excising aortas before fixation resulted in contraction of sub-endothelial structures.
• Contraction artifacts complicated the interpretation of endothelial integrity in ex vivo fixed samples.

Conclusions:

• In situ fixation at physiological pressure is the preferred method for preserving rabbit aorta endothelium for SEM.
• Proper fixation techniques are critical for accurate morphological assessment of the endothelium.
• This methodology ensures reliable data for studies on vascular endothelium.