RESPON FISIOLOGIS LONG-TERM MEMORY TERHADAP PERUBAHAN MOLEKULER BDNF DI HIPOKAMPUS DAN PLASMA DARAH PADA BERBAGAI INTENSITAS AKTIVITAS FISIK TIKUS WISTAR

Abstract

Abstract

Long-term memory (LTM) is a physiological response of the nervous system that involves brain-derived neurotrophic factor (BDNF) in the hippocampus. LTM is the result of repeatedly and long-term potentiation of BDNF in the hippocampus. Beside of the hippocampus, BDNF can also be found in the blood plasma. Physical activity is one of the factors that play a role in the potentiation of BDNF in the hippocampus and blood plasma. But not yet known, the mechanism of the effect of physical activity in various intensity on the physiological respons of LTM and molecular changes of BDNF both in the hippocampus and the blood plasma. Similarly, unknown link between BDNF in the blood plasma with the molecular changes of BDNF in the hippocampus on the physiological  response mechanism of LTM. The purpose of this study was to analyze the physiological response of LTM to the molecular changes of BDNF in the hippocampus and blood plasma in the treatment of various intensities of wistar rats' physical activity. Subjects were male Wistar rats with 7-8 weeks of age and weighing between 201-250 grams. This research is an experimental study with pre (day-1) and post (day-14) design. LTM physiological response reflected by differences of travel time in swimming test. Molecular changes reflected by the changes in the expression of mRNA and protein of BDNF in the hippocampus and blood plasma BDNF. Treatment of physical activity on the subjects is running on the Animal Treadmill with grouping of the physical activity: light intensity at a speed of 10m/min, moderate intensity at a speed of 20 m/min and heavy intensity at a speed of 30 m/min. The treatment on the subjects with a duration of 30 minutes.Then, analysis of data on pre (day-1) and post (day-14) which are : LTM response based on travel time swimming test, the expression of mRNA and protein of BDNF in hippocampus based on RT-PCR and  immunohistochemistry and blood plasma BDNF expression by ELISA. The results showed
that moderate-intensity of physical activity is better in shortening the travel time (0.6260 vs 0.7270 vs 0.9400 vs 1.4000 min (p <0.05)), increase the expression of BDNF mRNA (17.2320 vs. 18.8800 vs 19.7540 vs 20.7750 Ct (p <0.05)), increase the expression of BDNF protein in the hippocampus by immunohistochemical staining preparations, as well as improving blood plasma BDNF levels (237.50010 vs. 102.67860 vs. 49.10720 vs. 7.14290 pg/ml (p <0.05)) compared with the light intensity, heavy intensity and control (t = -7.618 vs. -6.083 vs. -7.889 vs. -1.549, p <0.05 ). Similarly, in the group of moderate intensity physical activity, correlation and functional relationship between LTM with BDNF mRNA expression (Pearson r = -0.0764, p <0.05),  ippocampal BDNF protein (Spearman's rho: Body cell: r = -0.582 ; Axon: r = -0.436, p <0.05) and blood plasma BDNF levels (Pearson: r = 0.671, p <0.05), which is stronger than the light intensity, heavy intensity of physical activity and control (r2 = 100%, r2 = 96.7% = 65.7% r2, r2 = 17.8%). The conclusion was the moderate intensity of physical activity most well improve the LTM physiological response to the molecular changes of BDNF in the hippocampus and the blood plasma of Wistar rat.

Key words: Intensity, LTM, BDNF, hippocampus, plasma