Figure 4

Aberrant mechanical stress stimulated sensory nerve invasion into IVD tissues and deteriorates apoptosis of IVD cells. (a, b) Immunofluorescence staining for Cgrp expression (green) at 4- and 8-W post-surgery. DAPI stains nuclei blue. White arrows indicate high expression of Cgrp in AF. (c) Quantification of Cgrp-positive cells in AF region of (a, b). (d) Apoptosis images of the IVD sections. DAPI stains nuclei blue. White arrows indicate apoptosis in EP cells. (e) Quantification of apoptosis rate in (d). Data are shown as mean ± sem. Three independent experiments were performed in triplicate. *P < 0.05, **P < 0.01 compared to Sham group.