Remodeling Phase

Phase 3 remodeling begins after the large-scale entombment of the neural retina beneath the glial seal. Though the most aggressive remodeling occurs in this period, it has been studied least because it does not emerge until after the cone photoreceptors have been ablated. The time course of remodeling is not well-known yet and varies across models (Jones et al., 2003a, Marc et al., 2003), but phase 3 events do not appear until pnd 160 in the fastest models (e.g. the TG9N mouse) and more...

Introduction

During development, the CNS demonstrates a remarkable ability to regenerate damaged neuronal processes. New processes are able to grow through lesioned areas and even re-establish connections to their targets (Saunders et al., 1995). This ability has traditionally been considered lost in the adult mammalian CNS. Indeed, molecules have been identified on some CNS glia that specifically inhibit axonal growth in the adult (Chen et al., 2000). Recent evidence, however, suggests that the adult CNS...

Serotonin

Serotonergic projections and receptors in V1 Serotonin synthesis occurs through two enzymatic steps First the enzyme tryp-tophan hydroxylase catalyzes the conversion of the amino acid tryptophan into L-5-hydroxytryptophan 5-HTP , using tetrahydrobiopterin as a co-factor. Second, 5-HTP is decarboxylated by the enzyme aromatic L-amino acid decar-boxylase to form 5-hydroxytryptamine 5-HT serotonin , using pyridoxal phosphate as a co-factor. Serotonin has a wide cortical distribution, with high...