Glossary
Galanin
What is Galanin?
Galanin is a neuropeptide found throughout the central and peripheral nervous systems. It contains 29 or 30 amino acids, depending on the species, and acts through several receptor subtypes. Researchers study it in pain, mood, feeding, sleep, learning and memory.
Galanin and pain
Galanin can increase or reduce pain-related signaling, depending on the receptor subtype and site of action. This makes “more galanin means less pain” an inadequate description of the system.
Mood, appetite and sleep
Animal research links galanin signaling to feeding, sleep and depression-related behavior. Its effects vary with the circuit, receptor and experimental conditions. These findings identify processes to investigate rather than one general effect of changing galanin in humans.
Learning, memory and Alzheimer's disease
Galanin receptors occur in memory-related regions such as the hippocampus. Researchers have observed changes in galanin expression in studies of Alzheimer's disease. The role of those changes in the disease remains uncertain.
Why it matters
Galanin illustrates why a neuropeptide's name is not enough to predict its effect. Receptors and location matter. Its links with neuropathic pain, mood disorders and Alzheimer's disease make it a subject of treatment research, but a possible target is not an established treatment.