A Study on the Animal Model for Dementia Induced by Scopolamine

Eun-Jung Yoon1   Yunseo Choi1   Dongsun Park1,*   

1Korea National University of Education

Abstract

This study aimed to determine dose of scopolamine to induce cognitive and memory dysfunction in rat. Six-week-old male rats (n=20) were randomly divided four groups. Scopolamine bromide (0, 0.5, 1.0 and 2.0 mg/kg) was intraperitoneally injected for 7 days. From 4-7 days after injection, the rats were performed memory test by water maze and passive avoidance test. On the 8th day, the rats were sacrificed, then acetylcholinesterase (AChE) activity, cholinergic proteins and inflammatory mediators were analyzed from their brain tissue. In the memory test and AChE activity, the group of scopolamine treatment (0.5 mg/kg) showed no significant difference compared to the control group (0 mg/kg). But, they showed significant differences compared to the control group in expression of choline transporter, choline acetyltransferase, and vesicular acetylcholine transporter protein and nuclear factor kappa B, tumor necrosis factor-α, interLeukin-6, inducible nitric oxide synthase, and cyclooxygenase2 mRNA. Also, the groups of scopolamine treatment (1.0 and 2.0 mg/kg) showed significant differences compared to the control group in memory test, AChE activity, expression of cholinergic proteins and inflammatory mediators mRNA. Therefore, it was suggested that 1.0 mg/kg of scopolamine is adequate dose to induce cognitive and memory dysfunction in rats.

Figures & Tables

Fig. 1. Experimental schedules of scopolamine-induced memory impairments in the rats. Scopolamine (0, 0.5, 1.0, and 2.0 mg/kg) were intraperitoneally (i.p.) injected for 7 days. Memory test was performed 4-7 days using Morris water maze and passive avoidance test. The animals were sacrificed at 8 days, then AChE activity, western blot and real-time PCR were performed from brain tissues