FREE-RADICAL GENERATION DURING INFECTION WITH NIPPOSTRONGYLUS-BRASILIENSIS (NEMATODA) AND OR EIMERIA-NIESCHULZI (APICOMPLEXA)/

To determine if Eimeria nieschulzi suppresses Nippostrongylus brasilie nsis-induced self-cure in Sprague-Dawley rats by inhibiting free radic al production, jejunal free radical production was assessed using the Thiobarbituric Acid Assay in rats infected with 1 x 10(3) third-stage larvae of N. brasiliensis and/or 1 x 10(5) sporulated oocysts of E. ni eschulzi. Sham infected rats administered saline served as controls. R ats infected with N. brasiliensis were killed on day 11 postinoculatio n (PI) and those infected with E. nieschulzi on day 8 PI. Rats infecte d with both parasites were killed when day 8 PI with E. nieschulzi coi ncided with day 11 PI N. brasiliensis. Free radical production was ind irectly assessed by quantifying malondialdehyde (MDA), and data were e xpressed as a nM MDA x 10(-2)/mu g mucosal protein. No significant (P greater than or equal to 0.05) differences in MDA production were obse rved among the groups. Results of this study show that E. nieschulzi d oes not suppress N. brasiliensis self-cure by inhibition of free radic al production in Sprague-Dawley rats and, in fact, that this rat strai n does not increase jejunal free radical production in response to inf ection with either parasite.