PURPOSE: We induced neural stem cells (NSCs) to neurons by olfactory ensheathing cell (OEC) conditioned medium and characterized their electrophysiological properties after neuronal differentiation. METHODS: Fetal NSCs and OECs were cultured from embryonic day 14 SD rats and the conditioned medium was collected and stored at -20°C when the cell number was up to 80% of the culture flasks. The experiment groups were divided into a control group (cultured with DMEM/F12 without FBS) and an OECs induction group (cultured with OEC conditioned medium and DMEM/F12 without FBS). Immunocytochemistry staining was carried out to identify the neurons derived from NSCs and their electrophysiological properties were characterized after neuronal differentiation using a patch-clamp technique. RESULTS: The NSCs divided rapidly in the expansion medium, forming small proliferating spheres after 7 days. The OECs induction group presented an evident neuron-like type 7 days after adding OEC conditioned medium, and the nestin immunochemistry staining was positive. The electrophysiological characterization showed that the derived neurons presented a transient inward sodium current and slow outward potassium current under proper electric stimulus, which were blocked by tetrodotoxin (TTX) and tetraethylammonium (TEA). CONCLUSION: OEC conditioned medium can induce NSCs to form neurons, and electrophysiological characterization demonstrated that the derived neurons presented active electrophysiological properties which are essential for nervous excitation.
PURPOSE: We induced neural stem cells (NSCs) to neurons by olfactory ensheathing cell (OEC) conditioned medium and characterized their electrophysiological properties after neuronal differentiation. METHODS: Fetal NSCs and OECs were cultured from embryonic day 14 SD rats and the conditioned medium was collected and stored at -20°C when the cell number was up to 80% of the culture flasks. The experiment groups were divided into a control group (cultured with DMEM/F12 without FBS) and an OECs induction group (cultured with OEC conditioned medium and DMEM/F12 without FBS). Immunocytochemistry staining was carried out to identify the neurons derived from NSCs and their electrophysiological properties were characterized after neuronal differentiation using a patch-clamp technique. RESULTS: The NSCs divided rapidly in the expansion medium, forming small proliferating spheres after 7 days. The OECs induction group presented an evident neuron-like type 7 days after adding OEC conditioned medium, and the nestin immunochemistry staining was positive. The electrophysiological characterization showed that the derived neurons presented a transient inward sodium current and slow outward potassium current under proper electric stimulus, which were blocked by tetrodotoxin (TTX) and tetraethylammonium (TEA). CONCLUSION: OEC conditioned medium can induce NSCs to form neurons, and electrophysiological characterization demonstrated that the derived neurons presented active electrophysiological properties which are essential for nervous excitation.