Figure 8.

Comparison of BrdU labeling (A) and oligodendrocyte differentiation (B) in P7 OPCs cultured without TH for various periods of time in PDGF alone (open bars and symbols) and freshly isolated OPCs from adult optic nerve of equivalent age (filled bars and symbols). In all cases, OPCs were plated into PDL-coated slide flasks and cultured without TH in PDGF for 2 d. In A, BrdU was added for the last 8 h of the culture, and the cells were then fixed and stained for BrdU. An average of 1,000 cells were counted in duplicate flasks, and the results are shown as mean ± SEM. In B, either the cells were switched after the 2 d to culture medium without PDGF (−PDGF) or TH (+TH) was added for the time indicated. The proportion of differentiated oligodendrocytes was determined using morphological criteria. The results are shown as mean ± SEM of two experiments with duplicate flasks for each condition.