Studies On The Method For Collecting And Hatching Eggs Of Taenia Solium And Cytotoxicity Of Nitric Oxide To Oncospheres

Objective: 1) To establish a new method for collecting eggs of Taenia solium by digesting gravid proglottids by the acidity pepsin.2) To observe the number of eggs in gravid proglottids of Taenia solium by the new acidity pepsin method.3) To study the rule and factors of hatching eggs of Taenia solium by sodium hypochrite method.4) To study the in vitro larvicidal activity of nitric oxide (NO) to the oncospheres of Taenia solium.Methods: 1) The integrity and smashed gravid proglottids of Taenia solium were digested by pepsin solution in common or surge condition , then the time of digesting gravid proglottids was observed; the eggs in gravid proglottids collected by physical method and the remanent eggs in the gravid proglottids collected by pepsin method were counted, then the difference in the number of eggs collected by physical method or pepsin method was observed; the hatching rate of eggs and the viability of oncospheres were observed after the eggs collected by physical method or pepsin method and hatched by sodium hypochrite method; the hatching rate of eggs and the viability of oncospheres were observed after the gravid proglottids were digested 40min or 120min by pepsin solution and hatched by sodium hypochrite method; 2) Gravid proglottids of Taenia solium were digested by pepsin. Then the eggs werecollected and counted;3) The eggs of Taenia solium were hatched by sodium hypochrite solution in different concentration, then the hatching rate of eggs and the viability of oncospheres were observed in different time; the hatching process with 1% sodium hypochrite solution was observed;4) Macrophages were induced by LPS to produce NO, and the oncospheres were added to the medium with activated macrophages, then the larvicidal activity was observed; in order to further comfirm the effect of NO, the inhibitors of iNOS, Dexamethasone(DXS) and N w -nitro-L-arginine (L-NNA), were used to inhibit the production of NO, larvicidal activity was measured by the same methods and the difference of dead larvae ratio was compared between the inhibited and uninhibited groups.Results: l)The time of gravid proglottids digested by pepsin solution in surge condition was less than in common condition(P<0.01), and the time of the integrity gravid proglottids digested by pepsin solution was less than the smashed(P<0.01); the number of eggs collected by pepsin method was more than that by physical method (>6%);the hatching rate of eggs and the viability of oncospheres after the eggs collected by physical method or pepsin method and hatched by sodium hypochrite method were not different(P>0.05); the hatching rate of eggs and the viability of oncospheres after the gravid proglottids were digested 40min or 120min by pepsin solution and then hatched by sodium hypochrite method were not different(P>0.05);2) The number of the eggs in each mature gravid proglottid varied from 550 to 172500, and the average number was 26891. The difference of the eggs in gravid proglottids of different worms of Taenia solium was more prominent than that in gravid proglottids of the same worm of Taenia solium;3) The oncospheres can be obtained in all concentration except for that of 36%. The hatching rate rose with the concentration and the viability of oncospheres descreased 1with increase of the concentration and the eggs showed cytolytic quickly in highconcentration (36%). After the eggs of Taenia solium were hatched 5-6 minutes in 0.4%-1.0% sodium hypoehrite solution, the hatching rate of eggs and the viability was higher than the others; and though the process that the eggs of Taenia solium were hatched by 1% sodium hypoehrite solution was observed, we found the embryo membrane was dissolved and the oncospheres transgressed ;4) LPS can induce macrophages to produce NO effectively. The NO production of 2.0 x 105 macrophages was 119.6400+5.1154 u,mol,L, and the larvicidal effect reached to 79.83%. This activity can be inhibited by DXS and L-NNA. NO production and dead larvae ratio were reduced significantly in the inhibited gr...