RELEASE OF NITRIC-OXIDE FROM ASTROGLIAL CELLS - A KEY MECHANISM IN NEUROIMMUNE DISORDERS

Astrocytes are glial cells able to release nitric oxide (NO) under bas al conditions as well as following different neurochemical stimuli inc luding cytokines, endotoxins and soluble antigens, thereby participati ng in neuroimmune responses. In particular, the inducible isoform of N O synthase seems to be activated during co-incubation of this cell typ e with cytokines as well as in the presence of the HIV coating gp120 g lycoprotein, an effect which is associated with an enhancement of pros tanoid release. This seems also to occur via activation of cyclooxygen ase by NO. Thus, the L-arginine-NO pathway found in astrocytes may rep resent a novel approach in the treatment of neuroimmune disorders such as multiple sclerosis, Alzheimer's disease and AIDS.