Chronic variable stress alters inflammatory and cholinergic parameters in hippocampus of rats
Wyse ATS Biochemistry Department
Federal University do Rio Grande do Sul
Brazil
Abstract:
Stress is defined as an integrated bodily response that is produced to deal with extraordinary circumstances. While appropriate stress responses help in resisting diseases and are beneficial, severe and prolonged stress can be harmful. In the present study we investigated the effect of chronic variable stress (CVS) on some parameters of the immune system, including levels of cytokines [interleukin 1β (IL-1 β), interleukin 6 (IL-6), tumor necrosis factor α (TNF- α)] and chemokine CCL2 (MCP-1) in the hippocampus of rats. Acetylcholinesterase activity was also evaluated. Sixty-day old Wistar rats were submitted to different mild stressors for 40 days. After the last stress section, the cytokines and MCP-1 were determined by immunoassay and acetylcholinesterase activity by colorimetric method. Results showed that chronic stress significantly increased the levels of IL-1β, IL-6 and TNF-α, but did not alter the levels of MCP-1. In addition, acetylcholinesterase activity was increased in the hippocampus of rats subjected to CVS. These findings suggest that inflammation and cholinergic dysfunction may be, at least in part, important contributors to the neurological dysfunction observed in some depressed patients. Support: CNPq and FAPERGS.
