PMID- 16204637 OWN - NLM STAT- MEDLINE DCOM- 20060209 LR - 20071114 IS - 0741-5400 (Print) IS - 0741-5400 (Linking) VI - 78 IP - 6 DP - 2005 Dec TI - Are chemokines the third major system in the brain? PG - 1204-9 AB - Chemokines are a family of small proteins involved in cellular migration and intercellular communication. Although the chemokines and their receptors are located throughout the brain, they are not distributed uniformly. Among the chemokines and their receptors that are arrayed disproportionately in glia and neurons are monocyte chemotactic protein-1/CC chemokine ligand 2 (CCL2), stromal cell-derived factor-1/CXC chemokine ligand 12 (CXCL12), fractalkine/CX3C chemokine ligand 1, interferon-gamma-inducible-protein-10/CXCL10, macrophage inflammatory protein-1alpha/CCL3, and regulated on activation, normal T cell expressed and secreted/CCL5. In the brain, they are found in the hypothalamus, nucleus accumbens, limbic system, hippocampus, thalamus, cortex, and cerebellum. The uneven distribution suggests that there may be functional roles for the chemokine "system," comprised of chemokine ligands and their receptors. In addition to anatomical, immunohistochemical, and in vitro studies establishing the expression of the chemokine ligands and receptors, there is an increasing body of research that suggests that the chemokine system plays a crucial role in brain development and function. Our data indicate that the chemokine system can alter the actions of neuronally active pharmacological agents including the opioids and cannabinoids. Combined with evidence that the chemokine system in the brain interacts with neurotransmitter systems, we propose the following hypothesis: The endogenous chemokine system in the brain acts in concert with the neurotransmitter and neuropeptide systems to govern brain function. The chemokine system can thus be thought of as the third major transmitter system in the brain. FAU - Adler, Martin W AU - Adler MW AD - Center for Substance Abuse Research, Department of Pharmacology, Temple University School of Medicine, 3400 N. Broad Street, Philadelphia, PA 19140, USA. baldeagl@temple.edu FAU - Rogers, Thomas J AU - Rogers TJ LA - eng GR - DA-P30-13429/DA/NIDA NIH HHS/United States GR - DA06650/DA/NIDA NIH HHS/United States GR - DA07237/DA/NIDA NIH HHS/United States GR - DA14230/DA/NIDA NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural PT - Review DEP - 20051004 PL - England TA - J Leukoc Biol JT - Journal of leukocyte biology JID - 8405628 RN - 0 (Chemokines) RN - 0 (Neuropeptides) RN - 0 (Neurotransmitter Agents) RN - 0 (Psychotropic Drugs) RN - 0 (Receptors, Chemokine) SB - IM MH - Animals MH - Brain/*immunology MH - Cell Communication/*immunology MH - Chemokines/*immunology MH - Humans MH - Neuroglia/drug effects/immunology/metabolism MH - Neurons/drug effects/immunology/metabolism MH - Neuropeptides/metabolism MH - Neurotransmitter Agents/metabolism MH - Psychotropic Drugs/pharmacology MH - Receptors, Chemokine/*immunology MH - Signal Transduction/*immunology RF - 39 EDAT- 2005/10/06 09:00 MHDA- 2006/02/10 09:00 CRDT- 2005/10/06 09:00 PHST- 2005/10/06 09:00 [pubmed] PHST- 2006/02/10 09:00 [medline] PHST- 2005/10/06 09:00 [entrez] AID - jlb.0405222 [pii] AID - 10.1189/jlb.0405222 [doi] PST - ppublish SO - J Leukoc Biol. 2005 Dec;78(6):1204-9. doi: 10.1189/jlb.0405222. Epub 2005 Oct 4.