FIGURE 7.

Intracellular mechanisms underlying NPY-mediated neuroproliferation. NPY released by interneurons of the dentate hilus acts on NPY Y₁ receptors in the SGZ to initiate a neuroproliferative effect. The Y₁ GPCR activates nNOS, which synthesizes NO from l-arginine. The target of NO is sGC, which converts GTP into cGMP. cGMP activates PKG, which in turn leads to the activation of a range of protein targets or kinase pathways, ultimately resulting in ERK1/2 activation (phosphorylation). ERK1/2 are involved in regulating the expression of genes involved in controlling cell proliferation and differentiation (adapted from Ref. 23).