OBJECTIVE: To probe into the effects of recombinant human leukemia inhibitory factor（ LIF） protein on apoptosis of nucleus pulposus cells in rabbit intervertebral disc degeneration model. METHODS: The rabbit intervertebral disc degeneration model was established by acupuncture. The degeneration degree of rabbit intervertebral disc was observed by magnetic resonance imaging. Tissue protein was extracted from nucleus pulposus tissue. The LIF protein expression level in nucleus pulposus tissue was detected by Western Blot. Degenerated nucleus pulposus cells（ NPCs） were extracted. Flow cytometry was used to observe the effect of different concentrations of recombinant human LIF protein on apoptosis of degenerated NPCs. Western Blot was used to detect the effects of different concentrations of recombinant human LIF protein on extracellular matrix components and MAPK-ERK1/2 pathway protein expression. RESULTS: The intervertebral disc height and signal-to-noise ratio（ SNR） in the model group were lower than those in the control group

with statistically significant difference（ P < 0. 05）. The expression level of LIF protein in nucleus pulposus tissue of model group was higher than that of control group

with statistically significant difference（ P < 0. 05）. The difference of LIF protein expression level in rabbit nucleus pulposus tissue after acupuncture for 2 weeks

4 weeks and 8 weeks was statistically significant（ P < 0. 05）. The apoptosis rate of degenerated NPCs treated with 0

10

20

50 and 100 ng/ml recombinant human LIF protein were compared

and the differences were statistically significant（ P < 0. 05）. 0

10

20

50

and 100 ng/ml of restructuring LIF protein processing the degeneration of NPCs Aggtecan protein

collagen type Ⅱ and p-ERK1/2 protein expression level were compared

with statistically significant difference（ P < 0. 05）. CONCLUSIONS: LIF protein is highly expressed in the degenerated nucleus pulposus of rabbits

which may inhibit the apoptosis of nucleus pulposus cells by activating ERK1/2 pathway and promoting the synthesis of extracellular matrix. Recombinant LIF factor shows good prospect in delaying intervertebral disc degeneration.