Kinetics of the pulmonary phase of Schistosoma mansoni in mice treated with dexamethasone
Hermeto, M.V.; Bicalho, R.S.; de Melo, A.L.; Pereira, L.H.
Revista do Instituto de Medicina Tropical de Sao Paulo 32(3): 168-171
1990
ISSN/ISBN: 0036-4665 PMID: 2135369 Document Number: 363213
In the experimental schistosomiasis mansoni glucocorticoids cause a reduction in the worm burden when administered in the week of infection or, the longest, at the next week. In order to determine the probable(s) site(s) of reduction of the worm burden, mice were infected with cercariae of LE strain of Schistosoma mansoni and dexamethasone was administered daily (50 mg/kg, subcutaneously) starting 1 hour before infection until the eighth day. Mice were sacrificed daily starting on the third day after infection until the ninth day, and schistosomula from lungs were collected. Six weeks after infection, the remaining mice were sacrificed and perfused for adult worm recovery. Analysis of the results showed that the non-treated mice presented larger numbers of lung larvae than the treated ones, and this difference was also found later in the worm burden in the portal system. This difference may reflect the early death of larvae in treated animals, before or after reaching the lungs.