The functional role of galanin remains largely unknown; however, galanin is predominantly involved in the modulation and inhibition of action potentials in neurons. Galanin has been implicated in many biologically diverse functions, including: nociception, waking and sleep regulation, cognition, feeding, regulation of mood, regulation of blood pressure, it also has roles in development as well as acting as a trophic factor. Galanin neurons in the medial preoptic area of the hypothalamus may govern parental behaviour. Galanin is linked to a number of diseases including Alzheimer's disease, epilepsy as well as depression, eating disorders and cancer. Galanin appears to have neuroprotective activity as its biosynthesis is increased 2-10 fold upon axotomy in the peripheral nervous system as well as when seizure activity occurs in the brain. It may also promote neurogenesis.

 

Galanin is predominantly an inhibitory, hyperpolarizing neuropeptide and as such inhibits neurotransmitter release. Galanin is often co-localized with classical neurotransmitters such as acetylcholine, serotonin, and norepinephrine, and also with other neuromodulators such as neuropeptide Y, substance P, and vasoactive intestinal peptide.