Effect of propolis on learning and memory of streptozotocin-induced diabetic rats

Purpose of this study was to investigate effects of propolis application on learning and memory of diabetic rats exposed to streptozotosin (STZ). The study was conducted for four weeks by using radial maze with eight arms and included 51 male Sprague Dawley rats.The study included four experimental groups; control (C) (n=14), STZ application (STZ) (n=12), STZ exposure after propolis application (P+STZ) (n=12) and propolis application after STZ exposure (STZ+P) (n=13).The study focused on latent learning rate, short-term (STMF) and long-term memory failure (LTMF) rates, and duration for memory tasks. In addition, fasting blood glucose level, change in weights, plasma trace element levels and oxidative stress indicators were investigated.According to the findings of the study, fasting blood glucose levels of STZ group were higher than the other groups and propolis application decreased the glucose levels. Weight lost was also determined in the STZ group. Plasma Zn+2 levels of the rats exposed to propolis were higher than the other groups while there were no differences between groups in terms of other trace element and oxidative stress indicator levels. The most frequent STMF was in the STZ group while the most frequent LTMF was in the P+STZ group. The least frequent STMF and LTMF were in the STZ+ P group. Furthermore, the STZ group entered less number of total and correct arms in spite of their staying for longer time in the maze. The rats exposed to propolis entered similar number of total and correct arms with control group rats in similar time interval.