Galanin and NPY, two peptides with multiple putative roles in the nervous system

T. Hökfelt, C. Broberger, M. Diez, Z.-Q. Xu, T. Shi, J. Kopp, X. Zhang, K. Holmberg, M. Landry, J. Koistinaho
Horm Metab Res. 1999-05-01; 31(05): 330-334
DOI: 10.1055/s-2007-978748

Read on PubMed

1. Horm Metab Res. 1999 May;31(5):330-4.

Galanin and NPY, two peptides with multiple putative roles in the nervous system.

Hökfelt T(1), Broberger C, Diez M, Xu ZQ, Shi T, Kopp J, Zhang X, Holmberg K,
Landry M, Koistinaho J.

Author information:
(1)Dept. of Neuroscience, Karolinska Institutet, Stockholm, Sweden.

In the present brief overview we summarize results from several studies focusing
on two neuropeptides, galanin and neuropeptide Y (NPY) in discrete neuronal
systems, where they coexist with classic transmitters. On the basis of studies in
different animal models we propose that these peptides may be involved in
regulation of certain CNS functions and that drugs acting on their receptors may
be of use in new therapeutic strategies. At the spinal level galanin and NPY are
regulated in DRG neurons by nerve injury and in dorsal horn neurons by
inflammation. It is possible that this leads to attenuation of pain sensitivity.
Moreover, both peptides may exert trophic effects, for example to enhance
regeneration. In the hypothalamic arcuate nucleus NPY and its receptors are part
of the feeding circuitry, and we suggest that derangement of these NPY neurons
may at least in part underlay the lethal phenotype of anorectic mice, which die
22 days postnatally after showing decreased food intake and growth retardation.
Expression of NPY and NPY receptors is changed in the hippocampus of mice
comparatively early after prion inoculation, indicating that this peptide system
is affected in this spongiform degenerative disease in a region of importance for
learning and memory. Finally, galanin is co-localized with classic monoamine
transmitters in two central systems, the dorsal raphe serotonin neurons and the
locus coeruleus noradrenergic neurons. In both cases galanin causes
hyperpolarization (at high concentrations) and prolongs monoamine-induced outward
currents (at low concentrations), thus modulating activity in two systems of
importance for many brain functions including mood regulation. It may therefore
be interesting to analyse to what extent drugs affecting galaninergic
transmission also may be efficient in the treatment of, for example, depression.

DOI: 10.1055/s-2007-978748
PMID: 10422730 [Indexed for MEDLINE]

Know more about