Figure 3.

Changes in cGMP-mediated signaling in Alzheimer’s disease. The levels of nNOS, iNOS, pGC-A, and NO are increased, and the activity of NO-GC is reduced. Furthermore, amyloid-β inhibits NO-GC activity. Whereas the cGMP concentration in the CSF is reduced, the mean effect on the intracellular cGMP level is unknown. Possible targets for AD treatment are the stimulation of NO-GC and the inhibition of PDE inhibitors (see text for further explanations). CD36: cluster of differentiation 36; ONOO⁻: peroxynitrate, all other abbreviations are explained in the figure legend for Figure 1.