PARASITIC CASTRATION IN SNAILS--ROLE OF BIOGENIC AMINES

蜗牛的寄生阉割——生物胺的作用

• 批准号: 2413728
• 负责人: TIMOTHY P. YOSHINO
• 金额: $ 12.47万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-05-01 至 2000-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2413728
• 关键词: 5 hydroxytryptophan; Biomphalaria; Schistosoma mansoni; amines; autoradiography; central nervous system; decarboxylases; dihydroxyphenylalanine; dopamine; enzyme activity; fertility; helminthic antigen; hemolymph; host organism interaction; immunocytochemistry; oogenesis; parasitism; radiotracer; scintillation spectrometry; serotonin; serotonin receptor; spermatogenesis; tryptophan 5 monooxygenase; tyrosine 3 monooxygenase

DESCRIPTION: (Adapted from the Applicant's Abstract): Parasitic castration of snails by larval trematodes, which manifests itself as histopathological changes in the gonads and/or lowered oviposition, represents one of the most dramatic examples of how parasites are capable of modifying the host's internal environment to favor their own growth and reproduction. However, the molecular basis for this phenomenon is still unknown. Preliminary findings show that Schistosoma mansoni infection of the snail Biomphalaria glabrata leads to a depression in oviposition and concurrently in the levels of several host biogenic amines in the CNS and/or plasma, including L-dopa, dopamine, and serotonin. Since these bioamines regulate reproductive activity in other molluscs, this research proposal addresses the hypothesis that parasitic castration by larval schistosomes is due in part to parasite modulation of snail host bioamine levels or enzymes responsible for their synthesis. Using a combination of analytical methods to quantify bioamine levels and enzyme activities in snail tissues, in vivo inhibition experiments, and assays measuring bioamine interaction with host reproductive organs and larval S. mansoni, the investigator will address four specific aims: 1) to determine the effects of schistosome infection on bioamine levels in the central nervous system (CNS), gonads, albumin gland, and cell-free hemolymph (plasma) of the snail host, B. glabrata, 2) to determine the impact of larval infection on key enzymes involved in bioamine synthetic pathways in the CNS, 3) to assess effects of in vivo and in vitro monoamine manipulations on reproductive activity of infected and noninfected snails, and 4) to assess the ability of larval schistosomes to take up and metabolize, or inhibit activity of, host bioamines. Understanding the role of bioamines in snail reproduction and how parasites interfere with their activity may lead to novel methods of biological control based on metabolic disruption of egg production in the vector snail.

描述：（改编自申请人的摘要）：寄生虫 幼虫trematodes的蜗牛cast割，这表现为 性腺的组织病理学变化和/或降低的产卵， 代表了寄生虫如何能够的最戏剧性的例子之一 修改主机的内部环境以偏爱自己的成长 和繁殖。 但是，这种现象的分子基础是 仍然未知。 初步发现表明曼氏血吸虫 蜗牛生物传感的感染导致抑郁症 产卵和同时在几种宿主生物源的水平 中枢神经系统和/或血浆中的胺，包括L-Dopa，多巴胺和 5-羟色胺。 由于这些生物胺调节其他生殖活性 软体动物，该研究提案解决了寄生虫的假设 幼虫血块的cast割部分是由于寄生虫调节 蜗牛宿主的生物胺水平或负责其的酶 合成。 结合分析方法来量化 蜗牛组织中的生物胺水平和酶活性，体内 抑制实验和测量与生物胺相互作用的测定 主持人生殖器官和幼虫曼森，调查员将 解决四个具体目标：1）确定血块的影响 中枢神经系统（CNS）的生物胺水平感染， 蜗牛的性腺，白蛋白腺和无细胞血淋巴（等离子体） 宿主，B。Glabrata，2）确定幼虫感染对钥匙的影响 CNS中参与生物胺合成途径的酶，3）评估 体内和体外单胺操纵对生殖的影响 感染和未感染的蜗牛的活动，以及4）评估能力 幼虫血块的摄入和代谢或抑制活性 宿主生物胺。 了解生物胺在蜗牛中的作用 繁殖以及寄生虫如何干扰其活动可能导致 基于代谢破坏的新型生物控制方法 矢量蜗牛中的鸡蛋产量。