Dulbecco's Modified Eagle Medium is neuroprotective when compared to standard vitrectomy irrigation solution.

PURPOSE

Several iatrogenic risk factors during pars plana vitrectomy (PPV) could cause damage to the retina. One mechanism is excitotoxicity. Therefore, neuroprotective irrigation solutions would be desirable.

METHODS

Retinal ganglion cells (RGC-5) and retinal whole mounts were incubated in standard irrigation solution (SIS) and Dulbecco's Modified Eagle Medium (DMEM). Cell viability, cell amount, cell survival and caspase 3/7 activity were measured by MTS-Test, crystal-violet staining, Annexin-V/PI flow cytometry and caspase 3/7 activity assay, respectively. The morphology and the function of retinal whole mounts were analysed by Live/Dead(TM) staining and by the b-wave and a-wave of the electroretinogram (ERG).

RESULTS

Under excitotoxic conditions (10 mM and 12 mM glutamate) RGC-5 cells incubated in SIS showed a statistically significant reduction in cell viability, cell amount, cell survival and caspase 3/7 activity compared to DMEM. Furthermore, the incubation of retinal whole mounts in DMEM resulted in a significant decrease of cell death under excitotoxic (250 μM glutamate) and standard conditions compared to SIS. ERG b-wave recordings revealed good functional preservation of retinal whole mounts in DMEM, but loss in SIS.

CONCLUSION

DMEM seems to support retinal cells very well and to be strongly protective against excitotoxicity. Therefore, DMEM may be considered as possible neuroprotective irrigation solution for PPV.