Facilitatory Effect of IL-6 Deficiency on Long-Term Spatial Memory in Young Adult Mice
The significance of interleukin 6 (IL-6) in long-term reference memory was tested in the Morris water maze (MWM) in 4-month-old C57BL/6J IL-6-deficient (IL-6 KO) and control mice. Three-day learning measured by escape latency time to find the hidden platform was comparable in both genotypes. In a single probe trial performed 7 days later, without the platform, latency to the platform site and path length to the target place were significantly shorter (p < 0.05 and p < 0.02, respectively), and platform-site crossovers more frequent (p < 0.05) in IL-6 KO mice. The swimming speed in IL-6 KO mice was significantly lower during learning (p = 0.0025) but not in the probe trial. Lack of differences between genotypes in a hole-board and in an elevated plus maze indicates that the observed effects were memory specific. The facilitatory effect of IL-6 deficiency on long-term reference memory in MWM indicates that IL-6 plays a role in consolidation process.
KeywordsIL-6 Morris water maze Elevated plus maze Hole-board Mice
The authors wish to thank K. Filonczuk M.Sc. for assistance with animals.
The study was funded by Medical University of Bialystok, Project Numbers: 153-24721 and N/ST/ZB/16/001/1124.
Compliance with ethical standards
Conflict of interest
Izabela Bialuk and Maria Małgorzata Winnicka declare that they have no conflict of interest.
All applicable international, national, and/or institutional guidelines for the care and use of animals were followed.
Human and animal rights and informed consent
All procedures in the study involving animals were approved by the Local Animal Ethics Committee in Bialystok, Poland.
- Aniszewska A, Szymanski J, Winnicka MM, Turlejski K (2014) Interleukin 6 deficiency affects spontaneous activity of mice in age- and sex-dependent manner. Acta Neurobiol Exp 74(4):424–432Google Scholar
- Tancredi V, D’Antuono M, Cafe C, Giovedi S, Bue MC, D’Arcangelo G, Onofri F, Benfenati F (2000) The inhibitory effects of interleukin-6 on synaptic plasticity in the rat hippocampus are associated with an inhibition of mitogen-activated protein kinase ERK. J Neurochem 75(2):634–643PubMedCrossRefGoogle Scholar