Analysis of possible behavior changes by image processing techniques in high fructose corn syrup consuming rats

In this thesis, investigation between the possible relation between the consumption of High Fructose Corn Syrup (HFCS) and stress-related behavioral changes was aimed. Additionally, designing a software to evaluate the data acquired from the dark-light, open field and tail suspension tests to determine the depression- and anxiety-like tests was intended. In our study, we used 23 male Sprague-Dawley rats. Animals were equally divided into four groups as control, rats were administered with 20 % HFCS (F20) and 40 % HFCS (F40), and exposed stress. During the study period of 14 days, rats in the groups of F20 and F40 were administered with 20 and 40 % HFCS in drinking water, respectively, and stress group was subjected to restraint stress for 3 h in first week and 6 h in second week. The food and water consumption and weight of the rats were recorded. Rats were subjected to dark-light, open field and tail suspension tests on the study days of 10, 12 and 14, respectively. At the end of the study, blood samples were collected for various biochemical parameters were measured, and TRPM2 channel activity in brain tissues was determined by immunohistochemical methods in the rats. A software was designed evaluating the video recordings from the anxiety and stress tests automatically by using the LabVIEW Vision Development Module. At the end of the study, F20 group was found to have increased liquid consumption and body weight significantly increased compared to other groups. On the other hand, F40 group had decreased liquid and food intake and increased body weight, but these differences were non-significant compared to other groups. When the behavioral tests were analysed, it was found that stress group had significantly increased immobility time in the stress group during the tail suspension test compared to control group. Similar but non-significant increases in the immobility time were found in F20 and F40 groups. Light-dark test revealed a significant increase in the time spent in the dark compartment in the F20, F40 and stress groups compared to control group. The latency to time for the passage from the light to dark was found decreased but it was found non-significant. The number of crossing the lines in the open field test were found decreased in F20, F40 and stress groups but it was only significant for stress group compared to control. When the biochemical parameters were considered, serum glucose, insulin LDL, VLDL, triglyceride, total cholesterol, TOS and corticosterone levels were increased in F20 and F40 were increased, TAS levels did not change, and HDL levels were decreased. These were similar to the data from the stress group. The immunohistochemical analyses revealed that TRPM2 immunoreactivity in hippocampus, prefrontal cortex, nucleus accumbens and amygdala regions were significantly increased in the F20, F40 and stress groups compared to the control group. In conclusion, the behavioral tests, immunohistochemical and biochemical parameters of the animals consuming HFCS and the animals exposed to stress were found similar. This study is the first study showing immunohistochemically that HFCS consumption increases the TRPM2 channel activity in different brain regions. A novel software was designed for evaluation of the video recordings acquired in the behavioral tests and it was used in this study. Key words: Fructose, Stress, Behavior, TRPM2, Immunohistochemistry