The growth-associated protein GAP-43 appears in dorsal root ganglion cells and in the dorsal horn of the rat spinal cord following peripheral nerve injury

摘要: When adult dorsal root ganglion cells are dissociated and maintained in vitro, both the small dark large light neurons show increases growth-associated protein GAP-43, a membrane phosphoprotein associated with neuronal development plasticity. Immunoreactivity for GAP-43 appears cytoplasm of cell bodies as early 3.5 h post axotomy is present neurites growth cones soon they develop. At stages culture (4 to eight days) satellite/Schwann also immunoreactive GAP-43. Neurons isolated whole vitro become GAP-43-immunoreactive between 2 3 after axotomy. It takes three days however, cutting or crushing sciatic nerve rats vivo, immunoreactivity appear axotomized cells. can be detected central terminals primary afferent superficial laminae horn lumbar enlargement four cut crush. The intensity staining reaches peak at 21 becomes undetectable nine weeks following crush injury 36 cut. pattern identical distribution small-calibre terminals. Little no deep horn, but does ipsilateral gracile nucleus 22 injury. In investigating mechanism regulation, blockade axon transport vinblastine (10(-5) M-10(-4) M) capsaicin (1.5%) was found produce that crush, while electrical stimulation had effect. Axotomy sensory interruption periphery therefore acts trigger production body. transported peripheral afferents. CNS elevated levels may contribute an inappropriate synaptic reorganization could play role disorders follow