Departamento de Biologia, Centro de Estudos de Insetos Sociais, Campus de Rio Claro, UNESP-Univ. Estadual Paulista, Avenida 24-A, n.1515, Bela Vista, Rio Claro, São Paulo, 13506-900, Brazil.
Arch Environ Contam Toxicol. 2013 Apr;64(3):456-66. doi: 10.1007/s00244-012-9849-1. Epub 2012 Dec 9.
Fipronil is a neurotoxic insecticide that inhibits the gamma-aminobutyric acid receptor and can affect gustative perception, olfactory learning, and motor activity of the honeybee Apis mellifera. This study determined the lethal dose (LD50) and the lethal concentration (LC50) for Africanized honeybee and evaluated the toxicity of a sublethal dose of fipronil on neuron metabolic activity by way of histochemical analysis using cytochrome oxidase detection in brains from worker bees of different ages. In addition, the present study investigated the recovery mechanism by discontinuing the oral exposure to fipronil. The results showed that mushroom bodies of aged Africanized honeybees are affected by fipronil, which causes changes in metabolism by increasing the respiratory activity of mitochondria. In antennal lobes, the sublethal dose of fipronil did not cause an increase in metabolic activity. The recovery experiments showed that discontinued exposure to a diet contaminated with fipronil did not lead to recovery of neural activity. Our results show that even at very low concentrations, fipronil is harmful to honeybees and can induce several types of injuries to honeybee physiology.
氟虫腈是一种神经毒剂，它可以抑制γ-氨基丁酸受体，影响蜜蜂的味觉感知、嗅觉学习和运动活性。本研究确定了氟虫腈对非洲化蜜蜂的致死剂量 (LD50) 和致死浓度 (LC50)，并通过检测不同年龄工蜂大脑中的细胞色素氧化酶，用组织化学方法评估了亚致死剂量的氟虫腈对神经元代谢活性的毒性。此外，本研究还通过停止口服接触氟虫腈来研究其恢复机制。结果表明，氟虫腈会影响老年非洲化蜜蜂的蘑菇体，通过增加线粒体的呼吸活性来改变代谢。在触角叶中，亚致死剂量的氟虫腈不会引起代谢活性的增加。恢复实验表明，停止接触被氟虫腈污染的饮食不会导致神经活动的恢复。我们的结果表明，即使在非常低的浓度下，氟虫腈对蜜蜂也是有害的，并可能导致蜜蜂生理的几种损伤。
