Siju K P, Hansson Bill S, Ignell Rickard
Division of Chemical Ecology, Department of Plant Protection Biology, SLU, Box 44, 230 53 Alnarp, Sweden.
Arthropod Struct Dev. 2008 Jul;37(4):248-59. doi: 10.1016/j.asd.2007.12.001. Epub 2008 Jan 12.
Female mosquitoes depend on blood to complete their reproductive cycle and rely mainly on chemosensory systems to obtain blood meals. An immunocytochemical analysis reveals a number of serotonin-immunoreactive neurons that innervate the chemosensory systems, suggesting a potential role of serotonin in modulating chemosensory processes. In the primary olfactory system, we identify a single ipsilateral centrifugal neuron with arborizations in higher brain centers; the varicosities of this neuron display volumetric changes in response to both blood feeding and during a circadian rhythm. Six to eight pairs of serotonin-immunoreactive neurons are identified in the primary gustatory neuropil, including the subesophageal ganglion and tritocerebrum. The peripheral chemosensory organs, i.e. the antenna, the maxillary palp and the labium, are described as having extensive serotonergic neurohemal plexi. In addition, we describe the presence of serotonin-immunoreactive fibers in the mechanosensory Johnston's organ. Taking these results together, we discuss the potential role of serotonin as a neuromodulator in the chemosensory system of disease vector mosquitoes.
雌性蚊子依靠血液来完成其生殖周期，并且主要依靠化学感应系统来获取血餐。免疫细胞化学分析显示，有许多血清素免疫反应性神经元支配着化学感应系统，这表明血清素在调节化学感应过程中可能发挥作用。在初级嗅觉系统中，我们识别出一个在高级脑中枢有分支的同侧离心神经元；该神经元的曲张体在血液摄取和昼夜节律期间均表现出体积变化。在包括咽下神经节和后脑在内的初级味觉神经纤维网中，识别出六到八对血清素免疫反应性神经元。外周化学感应器官，即触角、下颚须和唇，被描述为具有广泛的血清素能神经血窦丛。此外，我们描述了在机械感觉性约翰斯顿器官中存在血清素免疫反应性纤维。综合这些结果，我们讨论了血清素作为神经调节剂在病媒蚊子化学感应系统中的潜在作用。
