RESUMO
Several parameters connected to histamine metabolism and mast cell number were examined in the lungs of rats infected with the nematode Nippostrongylus brasiliensis. Histamine levels as well as mast cell numbers were found to be increased on day 14 after infection and were elevated during the whole time of the experiment. Histidine decarboxylase activity also reached a peak on day 14. There was no measurable activity of diamine oxidase in the lungs of parasitized and normal rats. It is postulated that the increase in histidine decarboxylase activity and histamine concentration observed in the present study is related to the process of mastocytosis.
Assuntos
Histamina/metabolismo , Pneumopatias Parasitárias/metabolismo , Pulmão/metabolismo , Infecções por Nematoides/metabolismo , Amina Oxidase (contendo Cobre)/metabolismo , Animais , Histidina Descarboxilase/metabolismo , Pulmão/enzimologia , Pneumopatias Parasitárias/enzimologia , Masculino , Mastocitose/metabolismo , Infecções por Nematoides/enzimologia , Nippostrongylus , Ratos , Ratos EndogâmicosRESUMO
Interspecific interactions between Nippostrongylus brasiliensis and Eimeria nieschulzi were studied by measuring fecal lysophospholipase (LYPH) activity and relative numbers of peripheral eosinophils in rats singly or concurrently infected with one or both parasite species. Three groups of 10 rats each were inoculated with 2 X 10(3) N. brasiliensis L3 larvae and/or 5 X 10(5) E. nieschulzi sporulated oocysts. Groups 1 and 2 were infected with E. nieschulzi or N. brasiliensis, respectively. Group 3 rats were infected first with N. brasiliensis, followed on day 8 postinoculation (PI) with E. nieschulzi. Each rat served as its own control. Results revealed LYPH levels rose steadily in Group 2 rats, reaching significant peaks on days 10 and 12 PI before decreasing to control levels. Lysophospholipase activity in Groups 1 and 3, however, did not differ from control values. Group 2 rats also demonstrated peripheral eosinophilia, with peak values occurring on days 10, 12, 14, and 16 PI, while rats in Groups 1 and 3 exhibited no eosinophilia. These results demonstrate that E. nieschulzi suppressed intestinal LYPH activity and relative peripheral eosinophilia and demonstrate that a host's immune response to a single parasite may be significantly altered when a second parasite species is present.
Assuntos
Coccidiose/complicações , Eosinofilia/etiologia , Eosinófilos/enzimologia , Lisofosfolipase/metabolismo , Infecções por Nematoides/complicações , Fosfolipases/metabolismo , Animais , Coccidiose/sangue , Coccidiose/enzimologia , Fezes/enzimologia , Lisofosfolipase/sangue , Masculino , Infecções por Nematoides/sangue , Infecções por Nematoides/enzimologia , Nippostrongylus , Ratos , Organismos Livres de Patógenos EspecíficosRESUMO
Results suggest that malabsorption of amino acids which occurs during Eimeria nieschulzi and Nippostrongylus brasiliensis infections in rats is not due to impairment by intestinal inflammation of gamma-glutamyl transpeptidase activity.
Assuntos
Coccidiose/enzimologia , Enteropatias Parasitárias/enzimologia , Mucosa Intestinal/enzimologia , Infecções por Nematoides/enzimologia , Peroxidases/metabolismo , gama-Glutamiltransferase/metabolismo , Aminoácidos/metabolismo , Animais , Coccidiose/complicações , Coccidiose/metabolismo , Inflamação , Absorção Intestinal , Enteropatias Parasitárias/metabolismo , Intestino Delgado/enzimologia , Masculino , Infecções por Nematoides/complicações , Infecções por Nematoides/metabolismo , Nippostrongylus , Ratos , Fatores de TempoRESUMO
Alveolar macrophages (AM) of rats infected with 3000 Nippostrongylus brasiliensis infective larvae for 2, 8 or 32 days (D2, D8 or D32 AM) quantitatively surpassed AM from uninfected rats in one or more of IgG- or C3-dependent phagocytosis indices, beta-D-glucuronidase release, or spontaneous release of thymocyte activating factor (interleukin-1, IL-1) and hepatocyte stimulation factor (HSF). These observations suggest that N. brasiliensis infection results in the activation of AM. We have reported previously that a greater proportion of AM from infected rats expressed C3 receptors and were helminthocidal in vitro in the presence of complement than normal AM which were not helminthocidal. The acquisition of the activated state by AM during infection may play a role in vivo lung resistance against migrating helminth parasites.