Influence of Brain and Azadirachtin on Trypanosoma cruzi Development in the Vector, Rhodnius prolixus

• Published in: Experimental parasitology 1999-06, Vol.92 (2), p.100-108
• Main Authors: Gonzalez, M.S., Nogueira, N.F.S., Mello, C.B., De Souza, W., Schaub, G.A., Azambuja, P., Garcia, E.S.
• Format: Article
• Language: English
• Subjects: Animals; azadirachtin; Biological and medical sciences; biological development; brain; Brain - physiology; disease vectors; Ecdysone - pharmacology; ecdysteroids; Epithelium - drug effects; Epithelium - parasitology; Epithelium - ultrastructure; Fundamental and applied biological sciences. Psychology; Insect Vectors - drug effects; Insect Vectors - parasitology; Insect Vectors - ultrastructure; Insecticides - pharmacology; Intestines - drug effects; Intestines - parasitology; Intestines - ultrastructure; Limonins; Medically important nuisances and vectors, pests of stored products and materials: population survey and control; Microscopy, Electron, Scanning; midgut; Reduviidae; Rhodnius - drug effects; Rhodnius - parasitology; Rhodnius - ultrastructure; Rhodnius prolixus; Triterpenes - pharmacology; Trypanosoma cruzi; Trypanosoma cruzi - drug effects; Trypanosoma cruzi - growth & development; Trypanosoma cruzi - ultrastructure; ultrastructure; Vectors. Intermediate hosts
• ISSN: 0014-4894; 1090-2449
• DOI: 10.1006/expr.1998.4387

Gonzalez, M. S., Nogueira, N. F. S., Mello, C. B., De Souza, W., Schaub, G. A., Azambuja, P., and Garcia, E. S. 1999. Influence of brain and azadirachtin on Trypanosoma cruzi development in the vector, Rhodnius prolixus. Experimental Parasitology92, 100–108. Studies on the effects of decapitation, head transplantation, azadirachtin, and ecdysone therapy on the ultrastructural organization of the midgut of Rhodnius prolixus, a vector of the protozoan Trypanosoma cruzi, show a distinct effect on the organization of the epithelial cells. When insects are decapitated or treated with azadirachtin, the ultrastructural organiza tion of these compartments changed significantly and drastically blocked the development of T. cruzi infection. In converse experiments, head transplantation or oral therapy with ecdysone significantly re versed the T. cruzi infectivity and reestablished the organization of the stomach and intestine in decapitated or azadirachtin-treated insects. These results indicat that a brain factor, possibly the prothoracicotropic hormone which stimulates ecdysteroid production on the prothoracic glands, may act directly or indirectly on both the midgut cell organiza tion and the intestinal microenvironment, interfering in the trypanosome survival and infection of the vector R. prolixus.