A study on the chemotaxis of the larvae of Strongyloides ratti

1999 Fiscal Year Final Research Report Summary

• Project/Area Number: 10670231
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 寄生虫学(含医用動物学)
• Research Institution: KYUSHU UNIVERSITY
• Principal Investigator: TADA Isao Kyushu University, Dept. of Parasitology, Professor, 大学院・医学系研究科, 教授 (60064531)
• Co-Investigator(Kenkyū-buntansha): HIGO Hiroo Kyushu University, Dept. of Parasitology, Assistant, 大学院・医学系研究科, 助手 (80117225)
• Project Period (FY): 1998 – 1999
• Keywords: Strongyloides ratti / chemotaxis / third-stage larva / amphid / thermotaxis / enzyme suppression

Research Abstract

Aiming at the clarification of chemotaxis of Strongyloides ratti, a murine nematode parasite, we exaimined the behavior of the third stage larvae (L3) on an agarose plate adjusted with various concentrations of NaCl. The results obtained are as follows : 1) L3 were inhibited their movements at 500 mM or higher in NaCl. 2) L3 showed escaping behavior to lower concentration area in 80-500mM. 3) L3 moved freely in 80 mM or less, while they did not cross the line of 80 mM to higher zone. The movement was shown to be quite sharp in recognition of 80 mM NaCl concentration. The sensitivity thus shown on agarose plates was inhibited by various chemicals and enzymes such as β-glycosidase, β-galactosidase, hyaluronidase, trypsin, lipase, protease, phospholypase, soybean agglutinin, wheat germ agglutinin, spermidine. On this context, we examined the effects of some enzymes on the thermotaxis of this nematode. Hyaluronidase and β-Glucuronidase glucuronidase inhibited this sensitivity of L3 on agaroas. In vivo movements of L3, however, percutaneously inoculated into rats was not disturbed in the course of migration. Present study suggested that mucopolysaccharides derived from hyaluronic acid may play important roles in the amphids of the nematode movements.