Effect of thyroxine on munc-18 and syntaxin-1 expression in dorsal hippocampus of adult-onset hypothyroid rats

Submitted: 20 August 2011
Accepted: 12 January 2012
Published: 22 May 2012
Abstract Views: 783
PDF: 410
HTML: 1273
Publisher's note
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.

Authors

Adult-onset hypothyroidism induces a variety of impairments on hippocampus- dependent neurocognitive functioningin which many synaptic proteins in hippocampus neurons are involved. Here, we observed the effect of adult-onset hypothyroidism on the expression of syntaxin-1 and munc-18 in the dorsal hippocampus and whether the altered proteins could be restored by levothyroxine (T4) treatment. All rats were separated into 4 groups randomly: hypothyroid group, 5μg T4/100 g body weight (BW) treated group, 20 μg T4/100g BW treated group and control group. The radioimmunoassay kits were applied to assay the levels of serum T3 and T4, and the levels of syntaxin-1 and munc-18 in hippocampus were assessed by immunohistochemistry and Western blot. Both analysis corroborated that syntaxin-1 in the hypothyroid group was significantly higher. Munc-18 was lower in four layers of CA3 and dentate gyrus by immunohistochemistry. After two weeks of treatment with 5 μg T4/100g BW for hypothyroidism, syntaxin-1 levels were completely restored, whereas the recovery of munc-18 only located in two of the four impaired layers. Twenty μg T4/100g BW treatment normalized munc-18 levels. These data suggested that adult-onset hypothyroidism induced increment of syntaxin-1 and decrement of munc-18 in the dorsal hippocampus, which could be restored by T4 treatment. Larger dosage of T4 caused more effective restorations.

Dimensions

Altmetric

PlumX Metrics

Downloads

Download data is not yet available.

Citations

Supporting Agencies

This study was supported by the National Natural Science Foundation of China (30772301)

How to Cite

Zhu, Y., Ning, D., Wang, F., Liu, C., Xu, Y., Jia, X., & Zhu, D. (2012). Effect of thyroxine on munc-18 and syntaxin-1 expression in dorsal hippocampus of adult-onset hypothyroid rats. European Journal of Histochemistry, 56(2), e22. https://doi.org/10.4081/ejh.2012.22