FIG. 3.

(A) Dendritic lengths of quadriceps motoneurons after spinal cord injury (SCI). After contusion injury, surviving quadriceps motoneurons lost over 28% of their dendritic length. Treatment with arachidonyl trifluoromethyl ketone (ATK) attenuated this dendritic atrophy. *Significantly different from sham animals. Inset: Drawing of spinal gray matter divided into radial sectors for measure of quadriceps motoneuron dendritic distribution (B and E) and radial dendritic extent (C and F). (B) Length per radial bin of quadriceps dendrites of sham animals (unfilled bars) and injured animals that were either untreated (SCI+vehicle, gray bars) or treated with ATK (SCI+ATK, black bars). For graphic purposes, dendritic length measures have been collapsed into six bins of 60 degrees each. Quadriceps motoneuron dendritic arbors display a nonuniform distribution, with the majority of the arbor located between 300 and 120 degrees. After contusion injury, surviving quadriceps motoneurons in untreated animals had reduced dendritic lengths throughout the radial distribution. Treatment with ATK attenuated these reductions. *Significantly different from sham animals. (C) Radial extents of quadriceps dendrites of sham animals (unfilled bars) and injured animals that were either untreated (SCI+vehicle, gray bars) or treated with ATK (SCI+ATK, black bars). For graphic purposes, dendritic extent measures have been collapsed into six bins of 60 degrees each. After contusion injury, extent measures of surviving quadriceps motoneurons in SCI+vehicle and SCI+ATK animals did not differ from those of sham animals. (D) Dendritic lengths of quadriceps motoneurons of sham animals and injured animals that were either wild type (WT) or cPLA₂ knockout (KO). Genetic deletion of cPLA₂ attenuated SCI-induced dendritic atrophy. (E) Length per radial bin of quadriceps dendrites of sham animals (unfilled bars) and injured animals that were either WT (gray bars) or cPLA₂ KO mice (black bars). There is a significant effect of radial dendritic location. (F) Radial extents of quadriceps dendrites of sham animals (unfilled bars) and injured animals that were either WT (gray bars) or cPLA₂ KO mice (black bars). Radial dendritic extent did not differ across groups. cPLA₂, cytosolic phospholipase A₂.