Cơ chế gây suy giảm trí nhớ không gian do tiêm axit okadaic vào nhân Meynert basalis của chuột

Frontiers of Medicine in China - Tập 2 - Trang 147-153 - 2008
Qing Tian1, Bin Liu1, Xinwen Zhou1, Qian Tu1, Rong Liu1, Jianzhi Wang1
1Department of Pathophysiology, Hubei Provincial Key Laboratory of Neurological Disease, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China

Tóm tắt

Chúng tôi đã báo cáo trước đây rằng việc tiêm axit okadaic (OA) vào nhân Meynert basalis của chuột đã gây ra các rối loạn trí nhớ không gian. Nghiên cứu hiện tại được thiết kế để tìm hiểu sâu hơn về các cơ chế tiềm ẩn. Chúng tôi phát hiện rằng mức acetylcholine (Ach) trong hồi hải mã giảm đáng kể sau 24 giờ tiêm OA vào nhân Meynert basalis của chuột. Đồng thời, rối loạn trí nhớ không gian, ức chế PP-2A và hyperphosphorylation tau tại Ser-198/Ser-199/Ser-202 (epitope Tau-1) và Ser-396/Ser-404 (epitope PHF-1) đã được quan sát. Với việc phục hồi mức Ach của hồi hải mã về mức bình thường sau 48 và 72 giờ sau khi tiêm, các rối loạn trí nhớ không gian, ức chế PP-2A và hyperphosphorylation tau đã được đảo ngược. Nghiên cứu gợi ý rằng việc tiêm OA vào nhân Meynert basalis của chuột có thể làm suy giảm trí nhớ không gian phụ thuộc vào hồi hải mã thông qua việc tổn hại đường dẫn cholinergic giữa nhân Meynert basalis và hồi hải mã, và sự ức chế chọn lọc PP-2A cùng với hyperphosphorylation tau có thể ít nhất là một phần trong các cơ chế tiềm ẩn.

Từ khóa

#axit okadaic #nhân Meynert basalis #trí nhớ không gian #acetylcholine #hồi hải mã #rối loạn trí nhớ #hyperphosphorylation tau #ức chế PP-2A

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