Scaling factor relating conduction velocity and transverse axon profile for nonmyelinated alimentary nerves.

The transverse area of nonmyelinated axonal profiles was measured in alimentary nerves of sheep and rabbits and compared with areas calculated from direct measurements of axon profiles taken from the same nerves. We concluded that the length of the minor axis of nonmyelinated profiles is not a suitable measurement for the calculation of transverse area or average diameter in nonmyelinated axons without the use of appropriate correction factors. Hence the scaling factor relating conduction velocity and transverse axon profile calculated from the average derived diameter is different (1.49 to 1.62) from that using the minor axis alone (0.89 to 1.26).