RESUMEN
Rhodnius neglectus is a wild triatomine, vector of the protozoan Trypanosoma cruzi, which causes Chagas' disease, and feeds on the blood of small mammals, being essential for its growth and reproduction. Accessory glands of the female reproductive tract are important in insect reproduction, but their anatomy and histology in R. neglectus are poorly studied. The aim of this work was to describe the histology and histochemistry of the accessory gland of the female reproductive tract of R. neglectus. The reproductive tract of five females of R. neglectus was dissected and the accessory glands transferred to Zamboni's fixative solution, dehydrated in a crescent series of ethanol, embedded in historesin, sectioned at 2 µm thick, stained with toluidine blue for histological analysis or mercury bromophenol blue for detection of total proteins. The accessory gland R. neglectus is tubular, without branches, opening in the dorsal region of the vagina and differing along its length in proximal and distal regions. In the proximal region, the gland is lined by the cuticle with a layer of columnar cells associated with muscle fibers. In the distal region of the gland, the epithelium has spherical secretory cells with terminal apparatus and conducting canaliculi opening in the lumen through pores in the cuticle. Proteins were identified in the gland lumen, terminal apparatus, nucleus and cytoplasm of secretory cells. The histology of the R. neglectus gland is similar to that found in other species of this genus, but with variations in the shape and size of its distal region.
Asunto(s)
Enfermedad de Chagas , Rhodnius , Trypanosoma cruzi , Animales , Femenino , Rhodnius/anatomía & histología , Rhodnius/fisiología , Insectos Vectores/anatomía & histología , Insectos Vectores/fisiología , Trypanosoma cruzi/fisiología , Reproducción , MamíferosRESUMEN
Rhodnius neglectus is a wild triatomine, vector of the protozoan Trypanosoma cruzi, which causes Chagas' disease, and feeds on the blood of small mammals, being essential for its growth and reproduction. Accessory glands of the female reproductive tract are important in insect reproduction, but their anatomy and histology in R. neglectus are poorly studied. The aim of this work was to describe the histology and histochemistry of the accessory gland of the female reproductive tract of R. neglectus. The reproductive tract of five females of R. neglectus was dissected and the accessory glands transferred to Zamboni's fixative solution, dehydrated in a crescent series of ethanol, embedded in historesin, sectioned at 2 µm thick, stained with toluidine blue for histological analysis or mercury bromophenol blue for detection of total proteins. The accessory gland R. neglectus is tubular, without branches, opening in the dorsal region of the vagina and differing along its length in proximal and distal regions. In the proximal region, the gland is lined by the cuticle with a layer of columnar cells associated with muscle fibers. In the distal region of the gland, the epithelium has spherical secretory cells with terminal apparatus and conducting canaliculi opening in the lumen through pores in the cuticle. Proteins were identified in the gland lumen, terminal apparatus, nucleus and cytoplasm of secretory cells. The histology of the R. neglectus gland is similar to that found in other species of this genus, but with variations in the shape and size of its distal region.
Rhodnius neglectus é um triatomíneo silvestre, vetor do protozoário Trypanosoma cruzi, causador da doença de Chagas. Este inseto se alimenta do sangue de pequenos mamíferos, que é essencial para o seu crescimento e reprodução. As glândulas acessórias do sistema reprodutor feminino são importantes na reprodução de insetos, mas sua anatomia e histologia em R. neglectus são pouco conhecidas. O objetivo deste trabalho foi descrever a histologia e histoquímica da glândula acessória do aparelho reprodutor feminino de R. neglectus. O sistema reprodutor de cinco fêmeas de R. neglectus foi dissecado e as glândulas acessórias transferidas para solução fixadora de Zamboni, desidratadas em série crescente de etanol, embebidas em historesina, seccionadas com 2 µm de espessura, coradas com azul de toluidina para análise histológica ou submetidas ao teste de mercúrio-bromofenol para detecção de proteínas totais. O sistema reprodutor de R. neglectus tem uma glândula acessória tubular, sem ramificações, abrindo-se na região dorsal da vagina, sendo diferenciada em regiões proximal e distal. Na região proximal, a glândula é revestida internamente pela cutícula com uma camada de células colunares associadas a fibras musculares. Na região distal ocorrem células secretoras esféricas com aparato terminal e canalículos condutores que se abrem no lúmen da glândula através de poros na cutícula. O teste histoquímico revelou a presença de proteínas no lúmen da glândula e no aparato terminal, núcleo e citoplasma das células secretoras. A histologia da glândula de R. neglectus é semelhante à das espécies desse gênero, mas com variações na forma e no tamanho de sua região distal.