Plasma proteins in human peripheral nerve.

Area of Science:

• Neurology
• Immunofluorescence
• Vascular Biology

Background:

• The blood-nerve barrier regulates the passage of substances into the peripheral nervous system.
• Understanding plasma protein distribution is crucial for diagnosing and treating neuropathies.

Purpose of the Study:

• To investigate the distribution and permeability of plasma proteins in sural nerve biopsies.
• To correlate protein accumulation with specific neuropathological conditions.

Main Methods:

• Immunofluorescent technique applied to sural nerve biopsies from 25 neurological patients.
• Analysis of the distribution of nine plasma proteins with varying molecular weights.

Main Results:

• Endoneurial vessels exhibit normal, albeit unequal, permeability to plasma proteins.
• Increased permeability of nerve blood vessels is observed in pathological conditions.
• Proteins with molecular weight ≥ 340,000 accumulate in the perineurium, suggesting slow clearance.
• Hypertrophic neuropathy shows marked perineurial accumulation of plasma proteins.

Conclusions:

• Nerve blood vessel permeability is a key factor in protein extravasation and accumulation in neuropathies.
• Perineurial protein accumulation, particularly of larger proteins, is a significant finding in hypertrophic neuropathy.
• Immunofluorescence is a valuable tool for assessing blood-nerve barrier integrity and protein distribution in neurological diseases.