THE INHIBITORY EFFECT OF CALCIUM CHELATORS ON THE APOPTOSIS OF MOTOR NEURONS IN CULTURED ADULT MOUSE SPINAL CORD SLICES

Aim: The aim of this study was to investigate the inhibitory effect of calcium chelators on apoptosis of motor neurons in adult spinal cord slices. Materials and Methods: The thoracic region of adult mouse spinal cord was sliced by a tissue chopper into 400 μm sections and divided into four groups: 1freshly dissected slices (0 hour), 2control slices, 3slices treated by ethylene deamin tetra acetic acid (EDTA) and 4slices treated by ethylene glycol tetra acetic acid (EGTA). The control and treated slices were incubated in a culture medium for 6 hours. MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide] assay was used to evaluate the viability of the slices. To study motor neurons morphology, propidium iodide and Hoechst 33342 were used. Data were analyzed using oneway ANOVA and Tukey test, and means difference was considered significant at p<0.05. Results: Motor neurons from slices cultured for 6 hours displayed morphological features of apoptosis. The application of calcium chelators (EDTA and EGTA) not only increased the viability of the cultured slices, but also inhibited apoptosis in the motor neurons and increased the percentage of viable motor neurons. Conclusion: It could be concluded that apoptosis in motor neurons of cultured spinal cord slices might be due to increased level of intracellular calcium.