雄性棉铃虫感受性信息素的分子和神经机制研究进展

棉铃虫Helicoverpa armigera主要借助于性信息素通讯完成雌雄识别,实现交配和种群繁衍。关于棉铃虫感受性信息素机制的研究一直是我国化学生态学领域的热点和重心,研究结果有助于开发和改进棉铃虫防治的性引诱剂。本文将对棉铃虫雄虫感受雌虫释放的性信息素的机制进行综述,以期为深入研究棉铃虫及其他相关昆虫的性信息素感受的分子和神经机理提供参考。棉铃虫雌虫性信息素腺体合成和释放多种长链、饱和或非饱和的脂肪醛和醇等化合物,其中Z11-16:Ald为主要性信息素成分,Z9-16∶Ald和Z9-14∶Ald为次要性信息素成分,不同组分按一定比例混合可明显增强对雄性棉铃虫的引诱效果,而化合物Z11-16∶OH和高剂量的Z9-14∶Ald对性信息素引诱活性具有明显的抑制效果。相应地,雄性棉铃虫触角上A, B和C 3种类型的毛形感器能够感受这些信息化合物。A类型毛形感器内表达受体OR13感受Z11-16∶Ald,B类型毛形感器内表达OR14b感受Z9-14∶Ald,C类型毛形感器内表达OR6和OR16感受Z9-16∶Ald, Z9-14∶Ald, Z11-16:Ac和Z11-16∶OH。受体的表达位置和功能与不同类型毛形感器的电生理反应特性相一致。钙离子成像证明在棉铃虫触角叶内的3个扩大型神经纤维球接受这些气味信息,其中神经纤维球云状体接受Z11-16∶Ald,背中间后侧纤维球接受Z9-16∶Ald,背中间前侧纤维球接受Z9-14∶Ald, Z11-16∶Ac和Z11-16∶OH。这些研究成果在感器、受体和脑中枢水平上揭示了棉铃虫感受性信息素的机制,在这些研究基础上,我们认为需要深入开展以下方面的研究：(1)进一步鉴定相关性信息素受体的功能和定位;(2)深入研究脑内嗅觉高级中枢对性信息素信息的处理和整合神经机制;(3)明确棉铃虫性信息素感受受到寄主植物、光周期、温度、湿度等环境因素的影响及机制。     

In-vivo organ engineering: Perfusion of hepatocytes in a single liver lobe scaffold of living rats

Organ decellularization is emerging as a promising regenerative medicine approach as it is able to provide an acellular, three-dimensional biological scaffold material that can be seeded with living cells for organ reengineering. However this application is currently limited to donor-derived decellularized organs for reengineering in vitro and no study has been conducted for re-engineering the decellularized organ in vivo. We developed a novel technique of a single liver lobe decellularization in vivo in live animals. Using a surgical method to generate a by-pass circulation through the portal vein and infra-hepatic vena cava with a perfusion chamber system, we decellularized the single liver lobe and recellularized it with allogenic primary hepatocytes. Our results showed that the decellularization process in vivo can preserve the vascular structural network and functional characteristics of the native liver lobe. It allows for efficient recellularization of the decellularized liver lobe matrix with allogenic primary hepatocytes. Upon the re-establishment of blood circulation, the recellularized liver lobe is able to gain the function and the allogenic hepatocytes are able to secret albumin. Our findings provide a proof of principle for the in vivo reengineering of liver.     

Development of the labial pit organ glomerulus in the antennal lobe of the moth Manduca sexta: The role of afferent projections in the formation of identifiable olfactory glomeruli

Iterated neuropil modules called glomeruli are characteristic of primary olfactory centers in both vertebrates and invertebrates. To gain insight into the developmental mechanisms underlying the formation of such structured, organized neuropil, we have examined the development of an identified glomerulus in the olfactory (antennal) lobe of the moth Manduca sexta. The labial pit organ glomerulus (LPOG) receives bilateral sensory projections from the labial pit organs in the labial palps of the mouthparts, while other glomeruli in the antennal lobe receive unilateral projections from the antenna. Here, we chronicle the development of the LPOG under normal and perturbed conditions. Our findings suggest that the sensory axons of the labial pit organ, like those of the antenna, induce and shape growth of interneuronal arborizations, but specific features of interneuronal arborizations such as the relative position of glomerular arborizations within the antennal lobe are independent of both classes of afferent innervation. Labial pit organ axons and antennal axons exhibit a high degree of specificity for their respective target regions, independent of the presence or absence of the other class of afferent axon or the route taken to the antennal lobe. Specification of glomerular position is intrinsic to the antennal lobe rather than a consequence of competition between afferent axons. © 1999 John Wiley & Sons, Inc. J Neurobiol 40: 28–44, 1999     

Regulation of cyclic GMP elevation in the developing antennal lobe of the sphinx moth,Manduca sexta

In the moth, Manduca sexta, 3′,5′‐guanosine monophosphate (cGMP) is transiently elevated during adult development in about 100 neurons of the antennal lobe. We demonstrate that nearly all of these neurons are local interneurons of the lateral cluster I, that their capacity to show a strong cGMP response during development is regulated by the steroid hormone 20‐hydroxyecdysone, and that in a subpopulation of these neurons cGMP elevation seems to be controlled directly by the gaseous messenger molecule nitric oxide (NO). Treatment with the acetylcholine esterase inhibitor eserine, antennal nerve transection, and electrical stimulation of the antennae suggest that NO/cGMP signaling during development is an activity‐dependent process. Besides input from the antennae, input from the central brain and the ventral ganglia is involved in upregulating cGMP in the antennal‐lobe neurons. Possible sources are centrifugal aminergic neurons, since application of serotonin and histamine enhances the GMP signal in local interneurons. Comparing the time course of cGMP elevation with events occurring during development leads us to the hypothesis that the NO/cGMP signaling pathway might be involved in synapse formation of a subset of antennal‐lobe neurons. © 1999 John Wiley & Sons, Inc. J Neurobiol 41: 359–375, 1999     

Enhancement by serotonin of the growth in vitro of antennal lobe neurons of the sphinx moth Manduca sexta

Cell culture experiments have been used to examine the effects of serotonin [5-hydroxytryptamine (5-HT)] on the morphological development of antennal lobe (AL) neurons in the brain of the sphinx moth, Manduca sexta. The majority of cells used in this study were from animals at stage 5 of the 18 stages of metamorphic adult development. 5-HT did not affect the survival of M. sexta AL neurons in culture, but did increase the numbers of cells displaying features characteristic of certain cell types. Three morphologically distinct cell types were examined in detail. The principal effect of 5-HT on these neurons was enhancement of cell growth. The magnitude of responses to this amine was cell-type specific. Site-specific responses to 5-HT were apparent also in one cell type. Our results suggest that the effects of 5-HT can change during the course of metamorphic development. These changes coincide temporally with the development of fast, sodium-based action potentials. © 1996 John Wiley & Sons, Inc.     

昆虫嗅觉神经的计算机三维重建

基于激光扫描共聚焦显微镜平台的计算机三维重建在昆虫嗅觉神经研究中发挥了重要作用。对经荧光标记的神经组织采集系列光学切片并进行三维重建,在双翅目、鳞翅目、膜翅目、蜚蠊目昆虫中均有进展。触角叶是昆虫的初级嗅觉中心,触角叶的解剖学图谱是识别不同种和雌雄虫间嗅球体特定功能的先决条件。了解构成嗅觉传输途径的主要神经元的形态和空间关系是理解气味信息在中枢神经系统编码的基础。三维重建昆虫的嗅觉神经,对于探讨昆虫嗅觉在其寄主选择、觅食以及寻找配偶等行为中的作用具有非常重要的意义。     

Age-dependent plasticity of sex pheromone response in the moth, Agrotis ipsilon: Combined effects of octopamine and juvenile hormone

Male moths use sex pheromones to find their mating partners. In the moth, Agrotis ipsilon, the behavioral response and the neuron sensitivity within the primary olfactory centre, the antennal lobe (AL), to sex pheromone increase with age and juvenile hormone (JH) biosynthesis. By manipulating the JH level, we previously showed that JH controls this age-dependent neuronal plasticity, and that its effects are slow (within 2 days). We hypothesized that the hormonal effect might be indirect, and one neuromodulator candidate, which might serve as a mediator, is octopamine (OA). Here, we studied the effects of OA and an OA receptor antagonist, mianserin, on behavioral and AL neuron responses of mature and immature males during stimulation with sex pheromone. Our results indicate that, although OA injections enhanced the behavioral pheromone response in mature males, OA had no significant effect on behavior in immature males. However, mianserin injections decreased the behavioral response in mature males. AL neuron sensitivity increased after OA treatment in immature males, and decreased after mianserin treatment in mature males. Determination of OA levels in ALs of immature and mature males did not reveal any difference. To study the possible interactive effects of JH and OA, the behavioral pheromone response was analyzed in JH-deprived mature males injected with OA, and in immature males injected with fenoxycarb, a JH agonist, and mianserin. Results show that both JH and OA are necessary to elicit a behavioral response of A. ipsilon males to sex pheromone.     

γ-Aminobutyric acid immunostaining in the antennal lobe of the moth <Emphasis Type="Italic">Heliothis virescens</Emphasis> and its colocalization with neuropeptides

The antennal lobe is the primary processing center for olfactory information in insects. To understand further the neural circuitry of this brain area, we have investigated the distribution of γ-aminobutyric acid (GABA) and its colocalization with neuropeptides in the antennal lobe of the noctuid moth Heliothis virescens. Immunocytochemical experiments with an antiserum against GABA showed a large number of labeled somata in the antennal lobe; these somata were located exclusively in the lateral cell cluster. Stained neurites innervating all antennal-lobe glomeruli, including the male-specific macroglomerular complex, suggested a prominent role of GABA in processing olfactory information, including signals from pheromones, interspecifically acting odors, and plant odors. Fibers in two antennocerebral tracts (the middle and dorsal antennocerebral tract) exhibited prominent GABA immunoreactivity. Double-labeling experiments revealed that immunostaining for three neuropeptides, viz., A-type allatostatin, Manduca sexta allatotropin, and FMRFamide-related peptides, was largely colocalized with GABA in cell bodies of the lateral cell cluster. The general absence of peptide immunostaining in the antennocerebral tracts strongly indicated that these peptides were colocalized with GABA in local interneurons of the antennal lobe. In contrast, tachykinin-related peptides occurred in a distinct population of local antennal-lobe neurons that did not exhibit GABA immunostaining. Thus, local interneurons that were not GABAergic were present in the moth antennal lobe. This work was supported by the Norwegian University of Science and Technology (project no. 80902101).     

原发全面强直-阵挛型癫痫的体素形态学研究

采用基于体素形态学（voxel- based morphometry,VBM）的方法,分析了全面强直-阵挛型癫痫（epilepsy with generalized tonic clonic seizures,GTCS）患者的大脑结构异常情况。对31例临床诊断为GTCS的患者和31例正常志愿者,采集大脑三维（3-dimensional,3D）T1结构像,进行VBM全脑分析比较。通过GTCS患者组与正常对照组的比较,发现GTCS患者的双侧丘脑、双侧额叶、双侧岛叶、双侧小脑等区域的灰质体积有比较明显的减小,但没发现有意义的灰质体积增高的区域;患者双侧丘脑、左侧中央前回、左侧额内侧回、左侧额中回和其发病频率呈负相关,没有正相关的区域。结果显示,全面强直-阵挛型癫痫患者的大脑结构存在异常,说明大脑灰质体积的异常可能和全面强直-阵挛型癫痫的发病存在一定的关系。     

Modulation of Main Lobe for Superfocusing Using Subwavelength Metallic Heterostructures

A subwavelength metallic heterostructure is put forth for the purpose of suppressing sidelobes and improving superfocusing at a quasi-far field region. Improvement has been made by means of optimization of the heterostructure composed of structured Au and Ag thin films. By tuning thicknesses of both the structured Au and Ag films, we can modulate propagation distance of the plasmonic lens and beam width of main lobe for the superfocusing. A finite-difference and time-domain (FDTD) algorithm-based computational numerical calculation was carried out for analyzing the focusing performance and tuning ability of the metal films. Our computational calculation results show that the sidelobes which play negative role for the focusing can be suppressed significantly in the case of the metal film thicknesses of h _Au = 50 nm and h _Ag = 10 nm. Theoretically, the metallic structure with smaller thicknesses of the structured Au and Ag films is helpful for improving the focusing performance. This heterostructure-based device is possible to be used as a superlens or nanoprobe in data storage, nanometrology/inspection, and biosensing etc.