损伤性嗅觉诱发电位的实验研究

Electrically stimulated olfactory evoked potential in olfactory-lesioned rabbit

目的 建立损伤性嗅觉功能障碍动物模型 ,了解电刺激嗅觉诱发电位的特性及变化规律。方法 通过立体定位和电解损毁技术 ,对动物一侧或双侧嗅球造成损伤 ,动态观察损伤后不同时间点 (2 4h、4 8h和 1周 )嗅觉诱发电位的变化 ,并观察嗅球与嗅黏膜病理和超微结构改变。结果一侧嗅球损伤后 ,诱发电位N2波消失 ,N1和P1波潜伏期延长 ,波幅减小 ;双侧嗅球损伤后 ,表现为N1、N2波消失 ,仅记录到P1波 ,其潜伏期明显延长 ,波幅变化较大 ,以上改变均以 2 4～ 4 8h变化最显著。组织病理学和超微结构显示 ,2 4～ 4 8h嗅球周围大量炎性细胞浸润 ,神经元变性样改变。结论嗅球损伤程度不同 ,对嗅觉诱发电位的影响也不相同 ,这种改变是以其组织病理和超微结构变化为基础的。

Objective To develop olfactory dysfunctioned animal model by injuring olfactory blub(s) and to investigate the characteristics of olfactory evoked potential. Methods The changes of OEP in rabbits were observed at 24 h,48 h and 1w after olfactory bulb(s) were electrolytically injured. The pathological and ultrastructural changes of olfactory mucosa and olfactory bulb were also observed. Results When unilateral olfactory bulb was damaged,N2 vanished with elongated latencies and lowerd amplitudes of N1 and P1. When both olfactory bulbs were damaged ,N1 and N2 were absent,only P1 could be recorded. The latency was extended obviously and the amplitude had a big change. Histopathology and ultrastructure showed that there were a lot of inflammatory cells and degenerated neurons scattered around OB 24 hours to 48 hours after injure. It was observed that the olfactory cilia had distraction perversion and colliquefaction changes. Conclusion Different degree of olfactory bulb injury caused different effect on OEPs. These changes of potential were based on the histopathology and ultrastructure.