The mouse median nerve experimental model in regenerative research

Area of Science:

• Neuroscience
• Regenerative Medicine
• Animal Models

Background:

• The rat sciatic nerve crush injury is a common model for nerve regeneration research.
• Increasing use of transgenic mice necessitates a shift from rat to mouse models.
• Human nerve lesions often affect the median nerve, making it a relevant target.

Purpose of the Study:

• To describe a novel experimental model of median nerve lesion in mice.
• To evaluate functional recovery and nerve regeneration in this new model.

Main Methods:

• Median nerve injury was induced in a mouse model.
• Motor function recovery was assessed by finger flexor muscle contraction strength.
• Nerve regeneration was evaluated using stereological methods in light and electron microscopy.

Main Results:

• Motor function recovery reached control levels by 20 days post-injury.
• Stereological analysis revealed comparable numbers of regenerated myelinated fibers by 25 days, but with smaller diameter and thinner myelin.
• Electron microscopy identified more fibers than light microscopy due to detection of smaller caliber axons.

Conclusions:

• The described mouse median nerve injury model is suitable for studying nerve regeneration.
• The model demonstrates rapid functional recovery and significant axonal regeneration.
• Regenerated fibers exhibit altered morphology (smaller size, thinner myelin) compared to controls.