检测蟾蜍离体坐骨神经和腓肠肌生理功能的简便有效辅助装置

目的:设计一种检测蟾蜍离体坐骨神经动作电位和腓肠肌张力的简便有效辅助装置,并分析其实用性。方法:制作由固定坐骨神经和腓肠肌的坐骨神经槽和器官池组成的实验装置(L形管)。将蟾蜍离体坐骨神经-腓肠肌标本置于L形管中,利用BL-420S生物机能实验系统检测坐骨神经动作电位和腓肠肌张力。标本随机分为正常对照组、利多卡因神经组和肌肉组,每组6个标本。利多卡因组(0.05、0.2和1 g/L)用相应浓度的利多卡因处理后再用任氏液冲洗,通过分析其对神经和骨骼肌的可逆性麻醉作用,验证装置的实用性。结果:通过将标本固定于L形管,能够同时检测坐骨神经动作电位和腓肠肌张力曲线,且易于更换坐骨神经槽和器官池内液体。与对照组比较,0.05和0.2 g/L利多卡因使坐骨神经的阈强度和最大刺激强度显著性增高(P0.05),绝对不应期延长(P0.01),传导速度减慢(P0.01),1 g/L利多卡因完全阻滞神经传导。1 g/L利多卡因使腓肠肌的静息张力显著性升高(P0.01),最大单收缩幅度显著性降低(P0.01),但阈强度和最大刺激强度无统计学差异。冲洗后,坐骨神经和腓肠肌的观察指标完全或部分恢复到对照组水平。结论:作为辅助装置,L形管能够使蟾蜍离体坐骨神经动作电位和腓肠肌收缩性的检测更为便利。

A simple and effective auxiliary device for detection of physiologic function on isolated sciatic nerve and gastrocnemius in toads

AIM: To design a simple and effective auxiliary device for detection of the compound action potential (CAP) and the force on the isolated sciatic nerve and gastrocnemius in toads, and to investigate its practicability. METHODS: A simple "L" shape device (L tube), which was composed of a nerve chamber and an organ bath, was made for fixing the isolated sciatic nerve and gastrocnemius. After fixing, the sciatic CAP and the gastrocnemius force were detected by BL-420S data acquisition and analysis system. The specimens were radomly divided into control group, and the lidocaine nerve and muscle groups. The sciatic nerve or gastrocnemius of each lidocaine group was firstly treated with the corresponding concentration of lidocaine, and then washed out with Ringer's solution, and its reversible anesthetic action on nerve conduction and muscle force was analyzed to verify the practicability of the L tube device. RESULTS: The CAP and the force of the sciatic-gastrocnemius specimens were detected concurrently by fixing the specimens in the L tube, and the liquid in the nerve chamber and organ bath was changed easily. Compared with the control, lidocaine at 0.05 and 0.2 g/L significantly increased the sciatic threshold stimulus voltage and maximal stimulus voltage (P<0.05), prolonged the absolute refractory period (P<0.01), and slowed down the conduction velocity (P<0.01). Lidocaine at 1 g/L completely blocked the sciatic conduction. The rest tension of the gastrocnemius was increased, and the maximal twitch force was decreased significantly by 1 g/L lidocaine (P<0.01), but the threshold and maximal stimulus voltage did not show statistic difference. The parameters of the sicatic nerve and gastrocnemius completely or partially recovered to the control level after washing out.CONCLUSION: As an auxiliary device, L tube makes the detection of CAP and force on the isolated sciatic nerve and gastrocnemius in toads more conveniently.