Anxiety-like behavior in the elevated-plus maze tests and enhanced IL-1β, IL-6, NADPH oxidase-1, and iNOS mRNAs in the hippocampus during early stage of adjuvant arthritis in rats

• Published in: Neuroscience letters 2011-01, Vol.487 (2), p.250-254
• Main Authors: Skurlova, Martina, Stofkova, Andrea, Jurcovicova, Jana
• Format: Article
• Language: English
• Subjects: Adjuvant arthritis; Animals; Anxiety - complications; Anxiety - metabolism; Anxiety - psychology; Arthritis, Experimental - complications; Arthritis, Experimental - metabolism; Arthritis, Experimental - psychology; Biological and medical sciences; Diseases of the osteoarticular system; Elevated plus-maze; Fundamental and applied biological sciences. Psychology; Hippocampus; Hippocampus - metabolism; IL-1β; IL-6; iNOS; Interleukin-1beta - biosynthesis; Interleukin-6 - biosynthesis; Male; Maze Learning - physiology; Medical sciences; Miscellaneous. Osteoarticular involvement in other diseases; NADH, NADPH Oxidoreductases - biosynthesis; NADPH Oxidase 1; Nitric Oxide Synthase Type II - biosynthesis; NOX1; Rats; Rats, Inbred Lew; RNA, Messenger - biosynthesis; Vertebrates: nervous system and sense organs
• ISSN: 0304-3940; 1872-7972
• DOI: 10.1016/j.neulet.2010.10.032

▶ Early adjuvant arthritis (AA) induces anxiety, and affects locomotor. ▶ Early AA upregulates mRNAs for IL-1β, IL-6, iNOS, NAPDH oxidase1 in hippocampus. ▶ Early AA triggers oxidative stress in hippocampus and impairs behavior. We studied anxiety-like behavior in the elevated plus-maze (EPM) tests in male Lewis rats on days 2 and 4 of adjuvant arthritis (AA). In plasma we analyzed C-reactive protein (CRP), albumin, ACTH, corticosterone, in the hippocampus the mRNA expression of interleukin-1β (IL-1β), interleukin-6 (IL-6), corticotrophin releasing factor (CRH), NADPH oxidases NOX1 and NOX2, and inducible NO-synthase (iNOS). EPM tests showed a higher anxiety index in AA rats on days 2 and 4 and reduction of total entries. On days 2 and 4 we found reduced plasma albumin, enhanced CRP, ACTH and corticosterone, and in the hippocampus enhanced mRNA for NOX1 and IL-1β in AA rats, on day 4 we found enhanced mRNAs for iNOS and IL-6, and reduced mRNA for CRH. The mRNA for NOX2 did not change on any experimental day. These results suggest enhanced anxiety, as well as locomotor impairment during the early phase of AA that correlate with enhanced mRNA expressions of parameters of oxidative stress NOX1, iNOS, and inflammatory cytokines IL-1β and IL-6 in the hippocampus.