目的研究耳鸣大鼠耳蜗基底膜内毛细胞耳畸蛋白(Otoferlin)表达的变化,从而推测其在耳鸣的发生中可能的作用机制。方法将24只Wistar大鼠随机分成空白对照组、生理盐水组和耳鸣模型组3组,每组8只。通过腹腔注射水杨酸钠制造耳鸣模型并用饮水抑制法对耳鸣模型进行验证。造模成功后,运用实时荧光定量RT-PCR方法及Western blot方法检测Otoferlin的表达情况。结果采用水杨酸钠注射方法成功建立了大鼠耳鸣模型;与空白对照组相比,生理盐水组大鼠Otoferlin m RNA和蛋白表达无明显变化(P>0.05),而耳鸣模型组Otoferlin m RNA及蛋白表达水平显著升高(P<0.05)。结论耳鸣大鼠耳蜗基底膜内毛细胞Otoferlin m RNA及蛋白质合成改变,可能是耳鸣产生的机制之一。
Objective To investigate whether estrogen modulates learning and memory and long-term potentiation （LTP） in the hippocampus of rats with Alzheimer＇s disease （AD）. Methods The rats were divided into ovariectomy （OVX） and estrogen replacement therapy （ERT） groups. Rats in the ERT group received OVX, followed by ERT, while rats in the OVX group received only OVX. The rat model of AD was established by injection of 1 μL （10 μg/μL） amyloid-beta peptide 1-40（Aβ1-40） into the hippocampus. The learning and memory ability and LTP were determined by Morris water maze and electrophysiological method, respectively. Results The escape latency in Morris water maze significantly decreased in ERT group compared with that in OVX group （P 〈 0.05）. Besides, rats in ERT group exhibited a significant enhancement of the magnitude of LTP at 30 min after high-frequency stimulation （HFS）, compared with that in OVX group （P 〈 0.01）. Conclusion ERT can attenuate the cognitive deficits in the rat model of AD, and estrogen can regulate LTP and synaptic remodeling in AD rats.
