Cholinesterases as markers of the inflammatory process in rats infected with Leptospira interrogans serovar Icterohaemorrhagiae.

The aim of this study was evaluate changes in the cholinesterase activity in blood, lymphocytes and serum of rats infected with Leptospira interrogans serovar Icterohaemorrhagiae ('L. icterohaemorrhagiae'). Sixty adult Wistar rats were divided into six groups of 10 animals: three control groups and three test groups. The animals from the test groups were intraperitoneally inoculated with 1 ml medium containing 1 × 10(8) leptospires. The activity of acetylcholinesterase in blood and butyrylcholinesterase in serum increased on days 5 (P<0.05) and 30 (P<0.021) post-infection, respectively. A decrease in lymphocyte count was observed on days 15 (P<0.01) and 30 post-infection (P<0.05). On day 15 post-infection, acetylcholinesterase activity (P<0.001) in lymphocytes decreased in infected rats. However, on day 30 post-infection there was an increase in acetylcholinesterase activity in lymphocytes. In conclusion, our results showed that the activity of enzymes of the cholinergic system in the total blood, lymphocytes and serum is altered as a result of inflammation caused by infection with L. icterohaemorrhagiae. The possible causes of these alterations will be discussed in this paper.