ObjectiveTo establish the degenerative disc animal model in rhesus macaques and to verify its reliability with T1ρ, spin-lock imaging and T2-mapping MRI and histological observation. MethodsTwelve female rhesus macaques (aged 4-6 years, weighing 4.4-6.1 kg) were enrolled in the study. The L5, 6 intervertebral disk was used for the experimental group by injecting 1 mL bleomycin A5 (2 mg/mL) to its adjacent endplates to induce degeneration, and the L4,5 intervertebral disk for the control group by injecting 1 mL normal sodium to its adjacent endplates. T1ρ and T2-mapping relaxation time was examined by using MRI, and the histological observation was performed to evaluate the process of degeneration at 1, 4, and 12 weeks after operation. ResultsThere was no significant change of T1ρ, T2 map relaxation time in the control group at different time points before and after operation (P>0.05). In the experimental group, there was a significant decrease of T1ρ relaxation time from 4 weeks after operation, showing significant difference when compared with the values at pre-operation and 1 week after operation (P<0.05). The T2 map relaxation time decreased significantly at 12 weeks after operation, showing significant difference when compared with the values at the other time points (P<0.05). There was no significant difference between 2 groups at the other time points (P>0.05) except T1ρ relaxation time at 4 and 12 weeks and T2 map relaxation time at 12 weeks (P<0.05). No significant change of the percentage of the high intensity area of the operated discs was observed on T2WI of MRI after operation in 2 groups (P>0.05). The histological results showed that the number of nucleus pulposus decreased and arranged irregularly at 4 weeks, and there were fibrosis changes of nucleus pulposus and cleft of the inner annulus fibrosus at 12 weeks after operation in the experimental group. ConclusionDegeneration of lumbar intervertebral disc in rhesus macaques can be induced by injecting bleomycin A5. T1ρ-MRI may be an effective method to evaluate early degeneration of intervertebral disc.