WEB 2086, a platelet-activating factor antagonist, inhibits prophenoloxidase-activating system and hemocyte microaggregation reactions induced by Trypanosoma rangeli infection in Rhodnius prolixus hemolymph.
J Insect Physiol
; 52(7): 685-92, 2006 Jul.
Article
em En
| MEDLINE
| ID: mdl-16777137
The effects of the triazolodiazepine WEB 2086, a platelet-activating factor (PAF) antagonist, on hemocyte microaggregation and prophenoloxidase (proPO)-activating system in the hemolymph, hemocoelic infection and mortality in fifth-instar larvae of Rhodnius prolixus inoculated with Trypanosoma rangeli were investigated. Hemocoelic injection of short T. rangeli epimastigotes (1x10(4) parasites/insect) in R. prolixus that were previously fed with blood containing 1muM of WEB 2086 resulted in (i) reduced hemocyte microaggregations as well as an attenuated proPO system in the hemolymph and (ii) greater parasitemia and mortality among the insects. In vitro assays using hemolymph from insects previously fed with blood containing WEB 2086 exhibited attenuated hemocyte microaggregations when T. rangeli was employed as the inducer of the reaction, and this effect was not counteracted by PAF treatment. In vitro assays using hemolymph from insects previously fed with blood, regardless of WEB 2086 presence increased the PO activity when incubated with the parasites. However, the PO activity was drastically inhibited when hemolymph from insects fed with blood, whether or not it contained WEB 2086, was incubated with fat body homogenates from insects fed with blood containing WEB 2086. The addition of PAF did not enhance the PO activity. These analyses did not reveal any PAF influence on WEB 2086 effects in the two defense reactions.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Rhodnius
/
Azepinas
/
Triazóis
/
Trypanosoma
/
Inibidores da Agregação Plaquetária
/
Fator de Ativação de Plaquetas
/
Catecol Oxidase
/
Precursores Enzimáticos
/
Hemócitos
Limite:
Animals
Idioma:
En
Revista:
J Insect Physiol
Ano de publicação:
2006
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Reino Unido