Figure 2.

Melatonin can alleviate the development of IDD in a rat model. (A) A Schematic of the in vivo experiment. Two weeks after puncture of the caudal intervertebral disc at Co5/6, rats were i.p. injected with melatonin or both melatonin and luzindole every 3 days for 4 weeks (n=12 for per group). (B) T2-weighted MRI scans of the caudal intervertebral disc of rats after no puncture, puncture, puncture with melatonin (10 mg/kg), or puncture with both melatonin and luzindole (1 mg/kg). Red arrows indicate the affected intervertebral discs. (C) HE staining and safranin O staining of the affected intervertebral disc of rats treated with indicated treatments. Representative images of different magnifications were displayed. Scale bars: 500 μm, 200 μm and 100 μm for 40×, 100× and 200× images, respectively. (D) Pfirrmann score analysis of T2-weighted MRI images of the caudal intervertebral disc of rats followed by indicated treatments (n=6 for per group). (E) Histological scores of the affected intervertebral discs of rats treated with indicated treatments (n=6 for per group). * means P < 0.05 compared with the control group. # means P < 0.05 compared with the puncture group. & means P < 0.05 compared with the puncture with melatonin group.