Baglan Hugo, Lazzari Claudio, Guerrieri Fernando
Institut de Recherche sur la Biologie de l'Insecte UMR 7261, CNRS - Université François-Rabelais de Tours, France.
Institut de Recherche sur la Biologie de l'Insecte UMR 7261, CNRS - Université François-Rabelais de Tours, France.
J Insect Physiol. 2017 Apr;98:160-166. doi: 10.1016/j.jinsphys.2017.01.001. Epub 2017 Jan 7.
In spite of the mosquito Aedes aegypti being a vector of several infectious diseases, a limited number of studies has been undertaken on learning in this species. Moreover, larval stages have been neglected as model organisms, although they are active, aquatic and perform stereotyped behavioural responses, e.g. the escape response when disturbed. To study the learning abilities of mosquito larvae, we focused on habituation, a form of non-associative learning widely studied in vertebrates and invertebrates. Habituation was defined as the progressive and reversible decrease in response to a reiterative stimulus. We first aimed at confirming habituation of the escape response in mosquito larvae (4th instar). Then, we determined whether a mnesic trace was established. Larvae were individually stimulated with a visual danger stimulus inducing the escape response. We set up a protocol for testing larvae individually, allowing the control of different parameters that are crucial for the study of cognitive abilities. After 15 trials, the escape response of mosquitoes was significantly lower. A disturbance stimulus presented after the 15th trial, induced the escape response and reversed habituation. Retention was confirmed up to 1h after the last habituation trial. This original bioassay can be adapted for studying the physiology of learning and memory in mosquito larvae, for analysing the effects of chemicals in the water, the characterisation of the cognitive abilities related to the life history of different mosquito species across preimaginal stages.
尽管埃及伊蚊是多种传染病的传播媒介，但针对该物种学习行为的研究却为数不多。此外，幼虫阶段作为模式生物一直被忽视，尽管它们活跃于水中，且会表现出刻板的行为反应，比如受到干扰时的逃避反应。为了研究蚊子幼虫的学习能力，我们聚焦于习惯化，这是一种在脊椎动物和无脊椎动物中广泛研究的非联想学习形式。习惯化被定义为对重复刺激的反应逐渐且可逆地减弱。我们首先旨在确认蚊子幼虫（四龄幼虫）逃避反应的习惯化。然后，我们确定是否建立了记忆痕迹。用诱发逃避反应的视觉危险刺激分别刺激幼虫。我们制定了一个单独测试幼虫的方案，以便控制对认知能力研究至关重要的不同参数。经过15次试验后，蚊子的逃避反应显著降低。在第15次试验后呈现的干扰刺激诱发了逃避反应并逆转了习惯化。在最后一次习惯化试验后长达1小时仍证实有记忆保持。这种原始的生物测定法可用于研究蚊子幼虫学习和记忆的生理学，分析水中化学物质的影响，以及表征不同蚊子物种在imaginal前期与生活史相关的认知能力。
