成年期甲状腺功能减退症大鼠海马乙酰胆碱的变化  

Effects of hypothyroidism on adult rats hippocampus acetylcholine

作　　者：徐永霞[1] 王芬[1] 王囡[1] 蔡瑶俊[1] 朱德发[1] 

机构地区：[1]安徽医科大学第一附属医院老年内分泌科,合肥230022

出　　处：《中国临床保健杂志》2013年第3期289-291,I0002,共4页Chinese Journal of Clinical Healthcare

基　　金：国家自然科学基金资助项目(81272152)

摘　　要：目的研究成年期甲状腺功能减退症(甲减)大鼠海马内乙酰胆碱(ACh)含量、乙酰胆碱酯酶(AChE)活性变化,探讨成年期甲减引起认知功能损伤及其康复机制。方法丙基硫氧嘧啶诱导成年期甲减大鼠模型,并给予左甲状腺素(L-T4)、乙酰胆碱酯酶抑制剂(多奈哌齐,DON)或L-T4联合DON干预后,测定大鼠血清T3、T4和促甲状腺素释放激素(TSH)水平和海马内ACh含量及AChE活性。结果甲减大鼠血清T3、T4水平显著减低、TSH水平增加(P<0.05),L-T4、DON或L-T4+DON治疗后,甲减大鼠血清T3、T4、TSH均恢复至正常水平;甲减大鼠海马内ACh含量和AChE活性显著降低(P<0.05),L-T4治疗后大鼠海马内ACh含量和AChE活性恢复正常,DON治疗后大鼠海马内ACh含量恢复到正常水平,但AChE活性仍显著降低(P<0.01),L-T4+DON治疗后,大鼠海马内ACh含量有升高趋势,但AChE活性显著降低(P<0.05)。结论成年期大鼠甲减时海马内ACh含量降低,AChE活性被抑制,T4联合DON可提高甲减大鼠海马胆碱能系统活性。Objective To study the acetylcholine（ACh） concentration and the acetylcholinesterase（AChE） activity in hippocampus of hypothyroid adult rats, and clarify the mechanism of cognition dysfunction under hypothy- roidism in adult rats. Methods The hypothyroid adult rats were induced by adding 6-n-propyl-2-thiouracilin drinking water, and received the treatments. The levels of serum 33, T4, thyrotrophin-releasing hormone （ TSH）, and the ACh concentration and AChE activity in hippocampus were assayed. Results The levels of serum 33, T4 decreased with the increase of serum TSH（ P 〈 O. 05）, and the serum 33 ,T4, and TSH leves returned to normal state after the Levo- thyroxine（ L-T4 ） replacement therapy, AChE inhibitor donepezil（ DON）, or concentration of the L-T4 and DON treat- ment in hypothyroid adult rats. The ACh concentration and AChE activity in hippocampus decreased in adult-onset hypothyroidism（P 〈 0.05） ,the ACh concentration and AChE activity recovered to the control rats after the L-T4 treatment. In addition, DON treatment reversed the ACh concentration to normal, however, the AChE activity was still inhibited（P 〈 0.01 ）. When combination of L-T4 with DON to treat the hypothyroid rats,the ACh concentration in hip- pocampus had a tendency to increase with the low activity of AChE（P 〈 0.05 ）. Conclusion The ACh concentration of hippocampus is decreased, and the AChE activity is inhibited,the combination of L-T4 and DON could improve the activity of hippocampus cholinergic system in hypothyroid rats.

关 键 词：甲状腺功能减退症 乙酰胆碱 海马 大鼠 sprague—dawley 

分 类 号：R581.2[医药卫生—内分泌]