The neurotrophins are a small group of proteins whose binding at the tropomyosin related kinase (Trk) and p75 neurotrophin receptor transmembrane receptors triggers a cascade of signaling events that give rise to neurotrophic responses in neuronal cells and in vivo. Although neurotrophins have been evaluated for therapy for several human neurodegenerative diseases, their poor pharmacokinetic behavior has rendered their development largely unsuccessful. For this reason, several strategies are being explored to obtain small molecules that achieve the neurotrophic and neuroprotective effects attributed to neurotrophins. One strategy in which to achieve these effects is to develop compounds that affect Trk receptor activation. (c) 2002 Prous Science. All rights reserved.