Effect Of Deltamethrin On The Intracellular Calcium In The Bee Brain Cells And Preliminary Exploration Of The Mechanism

Honeybees are economically important insects providing various kinds of bee products. Besides,when we think of crop production, protection of endangered plants, development of ornamental plantsand ecological restoration, the honeybees are playing the most significant role through their vital plantpollination activities. However, the increased demand for food, human beings have developed varioustypes of agrochemicals like insecticides. With this, the impacts of the misused agrochemicals have beennoticed to affect the welfare of the honeybee population throughout the world. Hence, different scholarshave repeatedly recommended that studying the mechanisms of how honeybees got toxic by insecticidesis a paramount important to indicate and device ways to lessen the effects of insecticides on these vitallyimportant insects to the agricultural sector. Thus, with the help of Ion Ratio Imaging System, this thesishave been implemented focusing on studying the effect of deltamethrin (DM) of sub-lethal on theconcentration of intracellular free calcium and calcium channels when processing the bee brain neuralcells in vitro.As a result, this study has improved the techniques on both cultivation of bee brain neural cells andits adherent cells. Moreover, a systematic measurement approach, started from cultivating adherent cellsand ended in the Calcium Ion Ratio Imaging System, has been designed. It was also confirmed thatconcentration of bee brain neural cells was2μM with fluorescent dye of Fura-2AM and incubation timeof45min. This approach, thus, is expected to lay a basis for evaluation technique based on changes ofcells [Ca2+]i. Hence, the previous extensive approach, figuring out the effect of toxic substances tohoneybees using statistical experimental method usually used in the field of honeybee biology, will bereplaced. Furthermore, the experiment has showed that DM have regular significant influence on theneural cells [Ca2+]iof the bee brain. It has been also indicated that [Ca2+]ihas significantly increased atthe initial stages when extracellular fluid concentration reached above0.125mg/L. It also continued torise after300~400sec with significant differences. In contrast,[Ca2+]ihave still went through asignificant increase at the beginning when the concentration of extracellular fluid was below0.125mg/L. But it recovered gradually after300~400sec. However, there still existed a significant differencebetween recovered and normal ratios until DM concentration has reached as low as0.03125mg/L. This,therefore, has clearly indicated that DM has the potential to affect honeybee brain neural cells even withan extremely low concentration. The experiment has also proved that calcium ions in the extracellularfluid were coming into the cells through cell membrane calcium channels. With this, it has beenconfirmed that this channel was the reason why bee brain neural cells [Ca2+]iincreased when affectedby DM. Moreover, T-type calcium channel has been notified to be the main target of DM.