title: Effects of chemokine receptor signalling on cognition-like, emotion-like and sociability behaviours of CCR6 and CCR7 knockout mice.
abstract: Inflammation is regarded as an important mechanism of neuropsychiatric disorders. Chemokines, which are a part of the immune system, have effects on various aspects of brain function, but little is known about their effects on behaviour. We have compared the cognition-like behaviour (learning and spatial memory) of CCR6(-/-) and CCR7(-/-) mice with wild type (WT) C57BL/6 mice, in the Barnes maze, as well as a range of other behaviours, including exploratory, anxiety and depression-like behaviour, using a battery of tests. Levels of cytokines TNF-α, IL-1β and IL-6 were also measured. In the Barnes maze, CCR7(-/-) mice were shown to take longer to learn the location of the escape box on the 1st of 4 days of training. In the behavioural battery, CCR6(-/-) mice showed higher locomotor activity and lower anxiety in the open field test, and a lack of preference for social novelty in a sociability test. CCR7(-/-) mice behaved much like WT mice, although showed higher anxiety in Elevated Zero Maze. While baseline saccharin preference in a 2-bottle choice test, a test for anhedonia depression-like behaviour, was equal in all strains at baseline, weekly tests showed that both CCR6(-/-) and CCR7(-/-) mice developed a decreased preference for saccharin compared to WT over time. There were no differences between strains in any of the cytokines measured. These results suggest that chemokine receptors may play a role in cognition and learning behaviour, as well as anxiety and other behaviours, although the biological mechanisms are still unclear.
authors: Discipline of Psychiatry, University of Adelaide, Adelaide, Australia.
authors: E J
authors: EJ
authors: Jaehne
authors: Discipline of Psychiatry, University of Adelaide, Adelaide, Australia. Electronic address: Bernhard.Baune@Adelaide.edu.au.
authors: B T
authors: BT
authors: Baune
mesh_terms: D000818:Animals; D001835:Body Weight / Q000235:genetics; D002755:Choice Behavior / Q000502:physiology; D003071:Cognition / Q000502:physiology*; D016207:Cytokines / Q000378:metabolism; D004644:Emotions / Q000502:physiology*; D005106:Exploratory Behavior / Q000502:physiology; D005518:Food Preferences / Q000502:physiology; D018782:Maze Learning / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009043:Motor Activity / Q000235:genetics; D054399:Receptors, CCR6 / Q000172:deficiency*; D054400:Receptors, CCR7 / Q000172:deficiency*; D021641:Recognition, Psychology / Q000502:physiology; D012439:Saccharin / Q000008:administration & dosage; D015398:Signal Transduction / Q000502:physiology*; D012919:Social Behavior
chemical_list: C498126:CCR6 protein, mouse; C515371:Ccr7 protein, mouse; D016207:Cytokines; D054399:Receptors, CCR6; D054400:Receptors, CCR7; D012439:Saccharin
keywords: 3×Tg AD; Anxiety; CCR6; CCR7; Cognition; Depression; EAE; EZM; Elevated Zero Maze; FST; KO; LPS; NORT; PFC; Sociability; autoimmune encephalomyelitis; forced swim test; knockout; lipopolysaccharide; novel object recognition test; prefrontal cortex; triple transgenic Alzheimer's disease