K. Chung et al., ABNORMALITIES OF SYMPATHETIC INNERVATION IN THE AREA OF AN INJURED PERIPHERAL-NERVE IN A RAT MODEL OF NEUROPATHIC PAIN, Neuroscience letters, 162(1-2), 1993, pp. 85-88
Using the rat model that we have developed, a potential underlying mec
hanism for sympathetically maintained neuropathic pain (SMP) was explo
red. In rats showing neuropathic pain behaviors after a tight ligation
of the L, spinal nerve, putative sympathetic postganglionic fibers we
re examined in the injured spinal nerve and the dorsal root ganglion (
DRG), using immunohistochemical staining with antibody against tyrosin
e hydroxylase (TH). In the neuropathic rats, there was an increase in
the number of TH-immunolabeled fibers in the spinal nerve, and some DR
G cells were surrounded by the labeled fibers. These abnormalities of
sympathetic postganglionic innervation of the injured spinal nerve or
the DRG may be a part of the mechanisms underlying the development of
SMP.