The distribution of peptide-containing nerves in the synovia of the cat knee joint.

Synovial capsule in cats is extensively innervated by a network with axonal diameter ranging from 0.6-3 microns according to its position and neuropeptide content. Nerve markers such as Neuron Specific Enolase (NSE) and Neurofilament triplet protein (NF) could be observed only when the axonal fibre attained a critical diameter of over the 3 microns limit.