The CAD cell line is a variant of a CNS-derived Cath.a cell line established by targeted oncogenesis in transgenic mice. Cell differentiation of the cell line can be induced by "starvation," i.e., removal of serum from the culture medium (protein-free medium). The differentiated CAD cells extend long processes, which ultrastructurally contain abundant microtubules, intermediate filaments, and various synaptic vesicles/organelles in the varicose enlargements, thus resembling neurites. Histochemical studies demonstrated that the differentiated cells express a number of synaptic vesicle proteins, cytoskeletons, different neurotransmitter enzymes, neuropeptides, and glia proteins. The data suggest that the differentiated CAD cells may be a suitable model for studies of intraneuronal transport, recycling of receptors, and pharmacological investigations. (c) 2007 Wiley-Liss, Inc.