Changes in lectin, GAP-43 and neuropeptide staining in the rat superficial dorsal horn following experimental peripheral neuropathy.

The density and distribution of reactivity for two lectins (soybean agglutinin (SBA) and RL-29), growth associated protein-43 (GAP-43) and the neuropeptides substance P and calcitonin gene-related peptide were analyzed in the spinal cord dorsal horn of rats with an experimental peripheral neuropathy. Twenty-eight days postsurgery, the density of label for RL-29 and GAP-43 was increased in laminae I and II on the experimental compared to the control side. In contrast, the density of neuropeptide label was decreased in the same region. Furthermore, on the experimental side, the distribution of both SBA and RL-29 reactivity was increased, extending into lamina III. We hypothesize that the increases in density and distribution of reactivity for the lectins and GAP-43, as well as the decreases in neuropeptide reactivity, reflect injury-induced regenerative changes in primary afferent terminals.