除草剂草甘膦异丙胺盐水剂对中华大蟾蜍心电活动的影响

Influences of the herbicide glyphosate-isopropylammonium solution on heart activities of Bufo gargarizans

采用生物信号采集处理系统对草甘膦异丙胺盐胁迫条件下中华大蟾蜍(BufogargarizansCantor)的心率和心电活动的相关指标进行了测定和分析。不同浓度的草甘膦异丙胺盐溶液被喷施到中华大蟾蜍的体表,由皮肤进入体内而作用于心脏。试验结果表明:随着草甘膦异丙胺盐处理浓度的增大,中华大蟾蜍的心率减慢,心电图中P波、R波和T波的电压峰值降低,而P-R间期、QRS期和Q-T间期的时值延长。草甘膦异丙胺盐胁迫条件下,蟾蜍心率与心电图的各项指标有显著相关性,可用多元线性回归模型分别对蟾蜍心率与心电图中P、R、T波和P-R、QRS、Q-T间期的相关关系进行拟合。多元回归分析结果表明,蟾蜍心电图中Q-T间期值对心率的影响最大,可以推断草甘膦异丙胺盐主要是通过延长蟾蜍心电活动周期中Q-T间期时值即心室收缩期而延长心动周期,导致蟾蜍心率减慢。由此可见草甘膦异丙胺盐水剂的喷施对中华大蟾蜍心脏的电活动周期和机械活动周期均造成了一定影响。

By applying Biological Signal Recording and Monitoring System, this paper aims to study influences of the herbicide glyphosate-isopropylammonium （GIA） on heart rate and electrocardiogram （ECG） of Bufo gargarizans Cantor. GIA solutions sprayed on the toads＇ backs are absorbed through the skin and can effect cardiovascular function. Results show that as GIA concentrations increased, heart rate declined and the peak voltage of P wave, R wave and T wave in the ECG decreased. The time of the P-R interval, QRS duration and Q-T interval increased. Heart rate of the toads was statistically correlated with the indexes of the electrocardiogram waveform. Both the relationships between the heart rate and the peak voltage of the waves in ECG waveform and the relationships between the heart rate and the time of the intervals in ECG waveform can be fitted within a multiple linear regression model. The analysis of the multiple linear regression shows that Q-T interval in ECG contributed the most to the pace of heart rate. Because the Q-T interval in ECG waveform is the period for ventricular contraction, it can be deduced that the GIA solution slows down the heart rate of Bufo gargarizans by prolonging ventricular contraction. It can be concluded that the herbicide GIA affects the electronic and mechanical activity of the toad＇s heart .