[Topography and morphometric characteristics of NF200(+)-neurons of the spinal cord gray matter after deafferentation with capsaicin].

The study was performed in 80 female Wistar rats aged 3, 10, 20, 30, 60, 180 and 360 days to examine the effect of capsaicin deafferentation on the topography of neurons containing 200 kD neurofilaments (NF200(+)-neurons) in the gray matter of the spinal cord II thoracic segment. The deafferentation was modeled by a single subcutaneous administration of 150 mg/kg of capsaicin to 2-day-old rats. Intact rats (n = 40) served as a control. To demonstrate NF200(+)-neurons the cells were labeled with antibodies against NF200. To count the proportion of immunoreactive neurons, the total neuronal population was marked with NeuroTrace Fluorescent Nissl stain. The results of the work have shown that NF200(+)-neurons were found in the ventral horn, intermediate zone and the dorsal horn of the spinal cord and differed from each other in their morphometric characteristics. In capsaicin-treated animals, the numbers of medial and lateral NF200(+)-motoneurons and their cross-sectional area were similarly reduced in the spinal cord (plate IX). In the intermediate zone (plate VII) and in the dorsal horn (plates III-IV) the number of NF200(+)-neurons in capsaicin-treated animals was not changed but their cross-sectional area exceeded normal values.