CILIARY BEATING OF SCHISTOSOMA MIRACIDIUM-POSSIBLE INVOLVEMENT OF CYCLIC NCLEOTIDE AND ION CHANNEL

蟋蟀血吸虫纤毛跳动-可能涉及环核苷酸和离子通道

• 批准号: 07670285
• 负责人: AOKI Yoshiki
• 金额: $ 1.54万
• 依托单位: NAGASAKI UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07670285/
• 关键词: schistosome; miracidia; cilia; cAMP; cGMP; protein kinase A; K^+channel; イオンチャネル

The studies on regulation of ciliary motility in Paramecium encouraged us to investigate the control mechanisms of ciliary beat of schistosome miracidia. The present study aimed at investigating the possible involvement of cAMP,cGMP,protein kinase A and ion channels in signal transduction mechanisms of ciliary beat of schistosome miracidia.Schistosome miracidia swim in water by means of numerous cilia which cover the body surface. The miracidia stop swimming in 1% NaCL solution. Addition of membrane permeable cAMP or cGMP causes about 40% of miracidia to swim under high osmotic pressure, the swimming speed is about 1/6 of that of miracidia swimming in water though. Addition of forskolin, an activator of adenyl cyclase and guanyl cyclase, and IBMX,an inhibitor or phosphodiesterase also caused miracidial forward swimming. The effect of these reagents was dose dependent.Cholera toxin increases adenyl cyclase activity of metazoan via tis effect on G-protein. However, cholera toxin did not have any effect on ciliary beat of miracidia. Inhibitor of protein kinase A,H88 and H89, inhibited miracidial swimming in water. K^+channel blocker, quinine and alpha dendrotixin, caused swimming of miracidia in water. Inhibitory effect of H88, H89, quinine and alpha dendrotoxin was dose dependent. Na^+channel blocker and Ca^<++>channel blocker did not have any effect on swimming of miracidia.These results suggest that cyclic nucleotide, protein kinase A and K^+channel regulate ciliary beat of schistosome miracidia.

草履虫纤毛运动调节的研究促使我们研究血吸虫纤毛跳动的控制机制。本研究旨在探讨cAMP、cGMP、蛋白激酶A和离子通道在毛吸虫纤毛搏动信号转导机制中的可能作用。毛吸虫依靠覆盖体表的大量纤毛在水中游动。毛毛虫在 1% NaCL 溶液中停止游动。添加膜渗透性的cAMP或cGMP使约40%的毛蚴在高渗透压下游动，但游动速度约为毛蚴在水中游动的1/6。添加毛喉素（一种腺苷酸环化酶和鸟苷酸环化酶的激活剂）和IBMX（一种磷酸二酯酶抑制剂）也会引起毛囊向前游动。这些试剂的作用是剂量依赖性的。霍乱毒素通过对G蛋白的作用来增加后生动物的腺苷酸环化酶活性。然而，霍乱毒素对毛蚴的纤毛跳动没有任何影响。蛋白激酶A、H88和H89抑制剂，抑制毛藻在水中的游泳。 K^+通道阻滞剂、奎宁和α树旋蛋白导致毛蚴在水中游动。 H88、H89、奎宁和α树毒素的抑制作用呈剂量依赖性。 Na^+通道阻滞剂和Ca^++通道阻滞剂对毛蚴的游动没有任何影响。这些结果表明环核苷酸、蛋白激酶A和K^+通道对血吸虫毛蚴的纤毛搏动具有调节作用。