Abstract: Objective To investigate the alterations of tight junction proteins in the duodenal mucosa of 6-hydroxydopamine (6-OHDA)-induced Parkinson’s disease (PD) models. Methods Rats were subjected with 6-OHDA in bilateral substantia nigra (SN) to make the PD models. The location and quantitative detecting techniques including immunohisto- chemistry and western blotting were used to determine the expressions and alterations of tight junction proteins (claudin-1, occludin, ZO-1). Results Claudin-1, occludin and ZO-1 were highly expressed in the duodenal mucosa of PD models, where the expressions of occluding (P<0.001) and ZO-1 (P<0.001) were much lower, while the expression of claudin-1 had no alteration. Conclusions The down-regulated expressions of occludin and ZO-1 were detected in duodenal mucosa of PD models, which might be related with duodenal ulcer in PD.

Key words: Key words: 6-OHDA models, duodenum, claudin-1, occluding, ZO-1