My watch list
my.bionity.com  
Login  

Neuropeptide Y



Neuropeptide Y
Structure of Neuropeptide Y. From PDB 1ron.
Available structures: 1f8p, 1fvn, 1icy, 1ron
Identifiers
Symbol(s) NPY; PYY4
External IDs OMIM: 162640 MGI: 97374 Homologene: 697
RNA expression pattern

More reference expression data

Orthologs
Human Mouse
Entrez 4852 109648
Ensembl ENSG00000122585 ENSMUSG00000029819
Uniprot P01303 P57774
Refseq NM_000905 (mRNA)
NP_000896 (protein)
NM_023456 (mRNA)
NP_075945 (protein)
Location Chr 7: 24.29 - 24.3 Mb Chr 6: 49.75 - 49.76 Mb
Pubmed search [1] [2]

Neuropeptide Y (NPY) is a 36 amino acid peptide neurotransmitter found in the brain and autonomic nervous system.

NPY has been associated with a number of physiologic processes in the brain, including the regulation of energy balance, memory and learning, and epilepsy.[1] The main effect is increased food intake and decreased physical activity.

In addition, NPY is secreted from the stomach. In addition to food intake, this increases the proportion of energy stored as fat and blocks nociceptive signals to the brain[2].

NPY also augments the vasoconstrictor effects of noradrenergic neurons.


Contents

Role in regulation of feeding

NPY's role in regulating energy balance is well known. It forms part of the "lipostat" system along with leptin and corticotropin-releasing hormone (CRH). High NPY levels in the cerebrospinal fluid are associated with high food intake and decreased physical activity. Leptin, produced by adipocytes in response to high fat levels, is detected by the arcuate nucleus in the hypothalamus. Increased arcuate nucleus activity acts on the paraventricular nucleus to inhibit the production of NPY at that site, thus reducing feeding behaviour. Arcuate nucleus activity also stimulates the release of CRH which further decreases feeding and increases energy expenditure.

Correlation with stress and diet

Studies of mice and monkeys show that repeated stress— and a high-fat, high-sugar diet— stimulate the release of neuropeptide Y, causing fat to build up in the abdomen. Researchers believe that by manipulating levels of the appetite hormone, they could make fat melt from areas where it was not desired and accumulate at sites where it is needed.[3][4]

Higher levels of NPY may be associated with resilience against and recovery from posttraumatic stress disorder.[5]

Receptors

Main article: Neuropeptide Y receptor

The receptor protein that NPY operates on is a G-protein coupled receptor in the rhodopsin like GPCR family. These receptors are metabotropic, causing metabolic changes in the target cell rather than directly opening ion channels. The protein contains seven membrane spanning domains and five subtypes have been identified in mammals, four of which are functional in humans.[6] Subtypes Y1 and Y5 have known roles in the stimulation of feeding while Y2 and Y4 seem to have roles in appetite inhibition (satiety). Some of these receptors are among the most highly conserved neuropeptide receptors.

See also

References

  1. ^ Colmers WF, El Bahn B (2003). "Neuropeptide Y and Epilepsy". Epilepsy Currents/American Epilepsy Society 2 (3): 53-8. PMID 15309085.
  2. ^ users.rcn.com - Hormones of the Gut
  3. ^ Thomas H. Maugh II. "Research points to way to eliminate belly fat", Chicago Tribune, July 2, 2007. 
  4. ^ Kuo, LE; Kitlinska JB, Tilan JU, Li L, Baker SB, Johnson MD, Lee EW, Burnett MS, Fricke ST, Kvetnansky R, Herzog H, Zukowska Z. (July 2007). "Neuropeptide Y acts directly in the periphery on fat tissue and mediates stress-induced obesity and metabolic syndrome". Nature Medicine 13 (7): 803-811.
  5. ^ Yehuda, Rachel; Brand, Sarah; Yang, Ren-Kui (April 2006). "Plasma Neuropeptide Y Concentrations in Combat Exposed Veterans: Relationship to Trauma Exposure, Recovery from PTSD, and Coping". Biological Psychiatry 59 (7): 660-663. ISSN 0006-3223. Retrieved on 2007-08-23.
  6. ^ Michel MC, Beck-Sickinger A, Cox H, Doods HN, Herzog H, Larhammar D, Quirion R, Schwartz T, Westfall T (1998). "XVI. International Union of Pharmacology recommendations for the nomenclature of neuropeptide Y, peptide YY, and pancreatic polypeptide receptors". Pharmacological Reviews 50 (1): 143-50. PMID 9549761.
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Neuropeptide_Y". A list of authors is available in Wikipedia.
Your browser is not current. Microsoft Internet Explorer 6.0 does not support some functions on Chemie.DE