Studies on control of ciliary activity in triton-extracted models of schistosome miracidia

本研究旨在探讨毛蚴表面纤毛活动的调控机制。本文报道了曼氏血吸虫（Schistosomamansoni）孵化毛蚴和壳内毛蚴的扫描电镜观察结果。毛蚴体表有3种纤毛，主要纤毛长8.5 μ m，宽0.25 μ m，除前端外，遍布体表。毛蚴在NaCl溶液中的游动速度测定结果表明，毛蚴的游动速度为1.25 μ m，在1.25 μ m的NaCl溶液中，毛蚴的游动速度为1.25 μ m。KCl和蔗糖酶溶液。毛蚴的游动速度是NaCl、KCl和蔗糖浓度的函数。这些结果表明毛蚴纤毛的搏动频率依赖于渗透压。用于精子Triton提取模型的提取和再活化溶液（Gibbons和Gibbons，1982）用于培养毛蚴。有趣的是，纤毛的跳动频率是NaCl浓度的函数。纤毛的跳动频率也与ATP、Mg++浓度和pH值有关。在标准再活化培养基（4 mMATP，1 mMMgSO_4，pH8.1）中，模型以活毛蚴在水中游泳速度的1/3（2 m/sec）游泳。Ca ~（++）可部分激活纤毛的搏动，但不引起纤毛搏动方向的逆转。其他二价阳离子没有激活纤毛跳动。VO 3抑制毛蚴纤毛的搏动，Ca++离子载体和佛波醇酯激活毛蚴纤毛的搏动。W-7、H-7和钙通道阻滞剂可抑制包裹在蛋壳内毛蚴的纤毛活动，其纤毛活动的药理学调控机制正在研究中。

The study was designed to explore the mechanism(s) of control of activity of cilia which are present all over the surface of schistosome miracidia. The hatched miracidia and miracidia enclosed within the eggshell of Schistosoma mansoni were used in this study.Scanning electron microscopy revealed that the body is covered with numerous cilia, 3 different cilia are present, and the major cilia are 8.5 mum in length and 0.25 mum in width, which distribute all over the surface except the anterior tip of the body.The swimming speed of miracidia was measured in NaCl, KCl and sucrase solution. The swimming speed of miracidia is a function of the concentration of NaCl, KCl and suorose. These results indicate that beating frequency of miracidial cilia is depend on the osmotic presure.Control of ciliary activities by exterally applied reagents was studied in triton-extracted model. The extraction and reactivating solution used for triton-extracted model of sperm(Gibbons and Gibbons, 1982)was used for schistosome miracidia. Interestingly enough the beating frequency of cilia is function of NaCl concentation. The beating frequency of cilia is also depend on ATP and Mg++ concentration and pH of medium. In a standard reactivating medium (4mM ATP,lmM MgSO4, pH8.1), the models swim at 1/3 of swimming speed of the live miracidia in water(2m/sec). Ca++ activated partially the ciliary beating, but did not cause the reversed direction of beating. Other divalent cations did not activate the ciliary beating. VO3 caused the inhibition of ciliary beating.Ca++ ionophore and phorbol esters activated the cilial beating of miracidia enclosed within the eggshell. W-7, H-7 and calcium channel blocker inhibited the cilial beating of miracidia enclosed within the eggshell.Pharmacological studies on control mechanism of ciliary activities is now in progress.