Role of nitric oxxide in host defense against Hymenolepis nama infection

ABSTRACT

The defensive role of nitric oxide [NO] against Hymenolepis nana was investigated in vivo and in vitro studies. Serum NO levels were increased in mice 5 days [cysticercoid stage] and 15 days [adult stage] after H. Nana induced oral infection with 1000 eggs/mouse compared with the normal controls. Meanwhile, L-NAME, a NO synthase inhibitor, oral administration in drinking water to infected mice caused a nonsignificant decrease in the serum NO levels compared with the normal controls and was associated with a significant increase in the number of both cysticercoids and adult worms compared with that in infected mice 5 and 15 days post infection. In an in vitro study, the NO donor, sodium nitroprusside caused an increased mortality rate of H. Nana cysticercoids and adult worms compared with the controls without NO donor and this was in a concentration-dependent manner. The implications of these results were discussed