Cyclic guanosine 3',5'-monophosphate-mediated neuroprotection by nitric oxide in dissociated cultures of rat dorsal root ganglion neurones

In dissociated cultures of dorsal root ganglia (DRG) derived from 15-day-old rats, many neurones expressed nitric oxide synthase (NOS) and this expression was found to be reduced by nerve growth factor. The application of blockers of NOS caused selective death of those neurones expressing NOS, The soluble guanylate cyclase (sGC) blocker ODQ also caused neuronal death. The appearance of the neurones undergoing cell death was typical of apoptosis. This suggests that NO has a neuroprotective action in DRG neurones which is probably mediated by its activation of cyclic guanosine 3',5'-monophosphate. These observations are discussed in relation to the developmental and neuropathic changes in NOS expression by DRG neurones. (C) 1997 Elsevier Science B.V.