Rafi F, Hassan R, Fatima H, Zafar F
Department of Physiology, University of Karachi.
Pak J Pharm Sci. 2000 Jul;13(2):13-9.
Optomotor normal visual response of the locust Schistocerca gregaria was compared when injected (between 1st and 2nd thoracic segments) with 10, 5, 2.5 and 1.25 microg/g body weight doses of Permethrin after different intervals of time (just after injection, 10 and 20 minutes). LD50 value for Permethrin was calculated to be 3.0 microg/g. Results are analyzed statistically by t. test and ANOVA technique. It was noticed that there was a significant decrease of vision (P<0.005, Table II) in treated locusts and at the same time Permethrine effect is significantly time related (P<0.05, ANOVA, table III). Correlation between increasing age, weight and increasing toxicity has also been established. The inhibition of neural enzyme Cholinesterase with Permethrin and as a result more accumulation of acetylcholine at nerve junctions and less passage of the transmission of impulses thus less response from the locusts has also been explored and discussed.
在不同时间间隔（注射后即刻、10分钟和20分钟），将体重剂量分别为10、5、2.5和1.25微克/克的氯菊酯注射到飞蝗（沙漠蝗）的第一和第二胸节之间，比较其视动正常视觉反应。计算出氯菊酯的半数致死剂量（LD50）值为3.0微克/克。结果采用t检验和方差分析技术进行统计学分析。结果发现，处理后的蝗虫视力显著下降（P<0.005，表II），同时氯菊酯的作用与时间显著相关（P<0.05，方差分析，表III）。还建立了年龄、体重增加与毒性增加之间的相关性。还探讨并讨论了氯菊酯对神经酶胆碱酯酶的抑制作用，以及由此导致的神经接头处乙酰胆碱积累增多、冲动传递减少，从而蝗虫反应减弱的现象。
