Graded inhibition of retrograde axonal transport by compression of rabbit vagus nerve.

Effects of experimental compression at different pressures on retrograde axonal transport were studied in rabbit vagus nerve. Proteins in the sensory neurones were radiolabelled by injection of [3H]leucine into the nodose ganglion. Sixteen hours after labelling, a small compression chamber and/or ligatures were applied around the cervical part of the vagus nerve for 8 h. Compression of the vagus nerve at 20, 30 and 200 mm Hg pressure induced a graded inhibition of both retrograde and anterograde transport of the radiolabelled proteins. Neither retrograde nor anterograde transport was affected by the presence of the non-inflated chamber. The results indicate that compression at pressures similar to those found in human carpal tunnel syndrome can block retrograde axonal transport. The consequences of inhibition of retrograde and anterograde axonal transport for the metabolism in the nerve cell bodies are discussed.