Manipulation of olfactory ensheathing cell signaling mechanisms: effects on their support for neurite regrowth from adult CNS neurons in coculture.

Pretreatment of olfactory ensheathing cells (OECs) with Pertussis toxin increased the number of subsequently cocultured adult retinal ganglion cells (RGCs) regrowing neurites without affecting neuronal survival. Pertussis toxin (PTx) inactivated an OEC G(i/o) protein as pretreating OECs with the PTx B-oligomer subunit had no effect on RGC neurite regrowth. However, the B-oligomer was responsible for decreasing the marked orientation of neurite regrowth on the OEC substrate. Simultaneous incubation of OECs with PTx and a depolarizing concentration of KCl abolished the increase in neurite regrowth from cocultured RGCs, but exposure to a depolarizing KCl concentration after OECs had been PTx-treated had no effect. Our evidence supports the hypothesis that G-protein-regulated calcium signaling plays a significant role in OEC support for CNS axonal regeneration.