关键词: 果蝇幼虫, 甲醚菊酯, 溴氰菊酯, 外周神经系统, 协同作用

Abstract: Electrophysiological effects of methothrin and deltamethrin on theexcitatory junction potentials (EJPs ) of the Drosophila larval neuromuscular junction were recorded by using an intracellular microelectrode. M ethothrin (1.49 x10^-8mol/L) caused high frequency spontaneous EJP spikes and repetitive discharges, while deltamethrin (1.0 x 10^-8mol/L) did not. This study revealed that methothrin could produce hyperexcitation (Type I action) in the peripheral nervous system of the Drosophila larvae, but deltamethrin did not (Type II action ).Combined application of methothrin and deltamethrin resulted in a compositeaction type, which showed both Type I and Type II action on spontaneous or stimulated EJPs. The frequency and duration of repetitive discharges or spontaneous spikes in the combined treatment were changed according to the proportions of methothrin and deltamethrin. This suggests that there may be a noncompetitive interaction between methothrin and deltamethrin during their joint action on the peripheral nervous system of the Drosophila larvae.

Key words: Drosophila larva, methothrin, deltamethrin, peripheral nervous system, joint action