Figure 3.

In situ hybridization of Schwann cell/neuronal cocultures. Cells were probed with biotin-labeled oligonucleotides and visualized under light microscopy with a strepavidin-alkaline phosphatase conjugate and NBT/BCIP (Life Technologies In Situ Hybridization and Detection System). The final probe concentrations were determined by serial dilutions until an adequate signal was obtained. All probes were verified by Northern blot analysis using the Life TechnologiesBRL (Gaithersburg, MD) BlueGene Nonradioactive Nucleic Acid Detection System. An oligonucleotide probe for 3β-HSD was applied to premyelinating (2 days after induction) and myelinating (5 days after induction) Schwann cell/neuronal cocultures (A, B). An oligonucleotide probe for cytochrome P450scc was also applied to premyelinating (C) and myelinating (D) cocultures.