Changes of cognitive function and spinophilin expression after partial hepatectomy in APP/PS1 transgenic mice

Abstract

Objective To investigate the effects of partial hepatectomy on spatial learning and memory abilities and the expression of spinophilin, which was used as a marker to quantify changes in dendritic spine density in the hippocampus of APP/PS1 transgenic mice. Methods 3-month-old and 6-month-old male APP/PS1 transgenic mice and 3-month-old wild-type male littermates were divided into five groups based on their genetic background: 3-month-old control (group A, n=8), anesthesia (group B, n=32), surgery (group C, n=32), littermates control(group D, n=8), 6-month-old control (group E, n=8). According to the different time points at day 1, 3, 7, 14 after anesthesia or surgery, group B and C were divided randomly into 4 subgroups: B1, B3, B7, B14 and C1, C3, C7, C14. The spatial learning and memory abilities were detected by Morris water maze test in each group at the corresponding time points. Meanwhile, spinophilin expression was detected by Western blot and Immunocytochemistry in the hippocampus. Results Compared with the same time point subgroup B, the latency to find a hidden platform was longer and the frequency of passing through the platform was decreased in Group C at day 3, 7, 14 (P 0.05). The grey value and Western blot relative integrated optical density of spinophilin in group A( 1 609 453±92 801/0.471±0.015 ), approached the Group D( 1 329 398.4±77 783/0.434±0.008 )(P>0.05), were significantly increased compared with that( 801 678±10 505/0.053±0.003 ) in group E (P<0. 01). Compared with the Group A, the same time point subgroup B and subgroup C14, the grey value and Western blot relative integrated optical density of spinophilin were decreased in Group C at day 1, 3, 7(P<0. 05). Conclusion Partial hepatectomy can impair spatial learning and memory abilities of the APP/PS1 transgenic mice, which is closely related to the decrease expression of spinophilin in hippocampus. Key words: Partial hepatectomy; APP/PS1 transgenic mice; Cognitive function; Spinophilin