FIGURE 3.

Expression of ATF3 in somatostatin (SOM), neurokinin-1 receptor (NK1R), and calbindin (CAL) subpopulations of L6-S1 preganglionic neurons one week after unilateral transection of the pelvic nerve. Representative horizontal sections of spinal cord immunolabeled for SOM, NK1R, or CAL (green) or ATF3 (red) are shown in A–C; higher magnification images from the same images are provided in the lower panels of each, as indicated by the boxes. Preganglionic neurons were identified by their uptake of retrograde tracer [FluoroGold (FG), here colorized blue]. Images are oriented with rostral at the top and lateral on the left (spared) or right (injured) of the relevant panel. Calibration bars represent 100 μm. ATF3 was only expressed in neurons on the injured side of the cord. (D) Injury reduced the proportion of preganglionic neurons expressing SOM (paired two-tailed t-test, P = 0.003; n = 5 rats). (E) Around half of the injured SOM-positive preganglionic neurons expressed ATF3; these comprised around one-third of the entire ATF3-positive population. (F) Injury reduced the proportion of preganglionic neurons expressing NK1R (paired two-tailed t-test, P = 0.043; n = 5 rats). (G) Around half of the injured NK1R-positive preganglionic neurons expressed ATF3; these comprised around one-third of the entire ATF3-positive population. (H) No effect of injury was detected on the proportion of preganglionic neurons expressing CAL (paired two-tailed t-test, P = 0.542; n = 5 rats). (I) Around half of the injured CAL-positive preganglionic neurons expressed ATF3; these comprised around one-third of the entire ATF3-positive population.