Fig 1.
Coronal sections and schematic drawings of a representative DCL at T2.
(A) Schematic representation of the thoracic lesion (gray area) according to the spinal cord (T2) atlas by Sengul et al. [53]; (B) Intact spinal cord (sham); (C) DCL of the spinal cord. Scale bar, 1 mm. In DCL rats, the ascending sensory fibers in the dorsal columns were damaged with minimal damage to the corticospinal tract. cc: central canal; cu: cuneate fasciculus; dcs: dorsal corticospinal tract; dl: dorsolateral fasciculus; IML: intermediolateral column; psdc: postsynaptic dorsal column pathway.
Fig 2.
Representative spectrograms of 50-kHz USVs during and after rhythmic stroking in two rats pre- and post-DCL or sham surgery.
(A) 50-kHz USVs during rhythmic stroking before surgery. (B) 50-kHz USVs after rhythmic stroking after surgery.
Fig 3.
Effects of a DCL on the number of 50-kHz USVs induced by rhythmic stroking.
The DCL decreased the number of 50-kHz USVs during and after stroking. * p < 0.01, **p < 0.001 compared to before stroking (baseline). Group means were compared by RM-ANOVA followed by post hoc Bonferroni tests for pair-wise comparisons. N = 8 rats/group.
Fig 4.
Effects of the DCL on the number of categorized 50-kHz USVs induced by rhythmic stroking.
Number of categorized 50-kHz USVs during (A) and after (B) rhythmic stroking in pre- and post-DCL/sham rats. The DCL decreased the number of total 50-kHz USVs during and after stroking. * p < 0.05, **p < 0.01 compared to the presurgery control using paired t-test. #p < 0.05 compared to the presurgery control using Wilcoxon Signed Rank test. †p < 0.05, ††p < 0.01 compared to the sham group using Mann–Whitney U test. §p < 0.001 compared to the sham group using unpaired t-test. N = 8 rats/group.
Fig 5.
Effects of the DCL on the behavioral activities.
(A) Rearing counts. (B) Exploring duration. (C) Locomotion duration. * p < 0.05; significant difference based on paired t-test. †p < 0.05; significant difference based on Mann–Whitney U test. N = 8 rats/group.
Fig 6.
Effects of the DCL on approach latency.
#p < 0.05; significant difference based on the Wilcoxon signed rank test. †p < 0.05; significant difference based on Mann–Whitney U test. N = 8 rats/group.
Fig 7.
Effects of DCL on mechanical sensory thresholds.
Tactile thresholds were determined by probing the plantar aspect of the hindpaw or abdomen with von Frey filaments by the “up-down” method (see text for details). The bilateral DCL resulted in an increase of hindpaw withdrawal thresholds but not in the abdomen. In the sham groups, the hindpaw and abdomen withdrawal thresholds did not change from preoperative values. #p < 0.05; significant difference based on the Wilcoxon signed rank test. †p < 0.05; significant difference based on Mann–Whitney U test. N = 8 rats/group.