Figure 3.

Example of the potential for reduction in the number of experimental animals using slice platforms for ex vivo studies. The example is based on the theoretical possibility to use the entire mouse spinal cord after coronal sectioning at a thickness of 400 μm. Rostro-caudal length of the cord is 32 mm at postnatal day 56 and 16 mm at postnatal day 4 (63). In theory it is possible obtaining up to 80 sections/animal (32,000:400) at P56, but a more reliable estimate is around 40 sections/animal. In P4 mice, corresponding figures are 40 (16,000:400) and 20 sections, respectively. It is then possible to cultivate 3–5 slices in 3 cm culture dishes, so that each culture is treated under different experimental conditions. The percentage of reduction thus goes from 75% (P4) to 87.5% (P56).