Objective: To develop an in vivo intervertebral disc organ culture model for a physiological environment and evaluate its clinical significance.
Methods: Murine functional spine units (FSUs) were isolated from 10-week-old mouse lumbar spines. FSUs consisted of two vertebrae surrounding one disc. Murine FSUs were cultured in medium and different concentrations of bupivacaine for different periods. Histological change and cell viability within intervertebral disc tissue were assessed by histological staining and MTT (3-(4,5-cimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay.
Results: Murine disc organs cultured for up to 4 weeks showed minimal changes in tissue histology and cell viability. A 1-hour incubation in 0.25% bupivacaine resulted in about 25% cell death while 0.5% bupivacaine exposure yielded 60% cell death over the same time.
Conclusion: Murine intervertebral disc maintains the integrity of tissue structures and cell functions for an ex vivo 4-week culture. And the exposure to bupivacaine dramatically decreases cell viability in a dose-dependent manner.