RESUMEN
Alkaline phosphatase activity was detected in salivary gland cells of the Rhodnius neglectus Lent, 1954, and R. prolixus Stal, 1859, vectors of Trypanosoma cruzi Chagas, 1909 (etiological agent of Chagas disease) and T. rangeli Tejera, 1920 (pathogenic to insect). The Gomori technique was used to demonstrate alkaline phosphatase activity. Alkaline phosphatase activity was observed throughout the entire gland, with an increased activity in the posterior region of the principal gland. In particular, phosphatase activity was found in the nucleolar corpuscles, suggesting a relationship with the rRNA transcription and ribosomal biogenesis. Alkaline phosphatase was also detected in the nuclear membrane and nuclear matrix, suggesting an association with the nucleo-cytoplasmic transport of ribonucleoproteins and the mechanisms of cell cycle and DNA replication, respectively. This study highlights the importance of alkaline phosphatase in the salivary gland of R. prolixus and R. neglectus and emphasizes its importance in secretory activity. Secretory activity is directly involved in hematophagy and, consequently, in development during metamorphosis. The observed presence of alkaline phosphatase suggests its involvement in the production of saliva allowing feeding of these insects that are important vectors of Chagas disease.
Asunto(s)
Fosfatasa Alcalina/metabolismo , Proteínas de Insectos/metabolismo , Insectos Vectores/enzimología , Rhodnius/enzimología , Glándulas Salivales/enzimología , Animales , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/transmisión , Femenino , Insectos Vectores/parasitología , Masculino , Rhodnius/parasitología , Glándulas Salivales/parasitología , Trypanosoma cruzi/fisiologíaRESUMEN
The human cases of eosinophilic meningitis recently reported from Brazil have focused the attention of the public health agencies on the role the introduced snail Achatina fulica plays as hosts of the metastrongylid nematodes. Determining the potential of this snail to host and develop infective larval stages of metastrongylids in the wild and identify the species harbored by them is crucial for designing effective control measures. Here we assess if A. fulica may act as intermediate host of A. cantonensis at the peridomiciliary areas of a patient's house from state of Pernambuco (PE), who was diagnosed with eosinophilic meningitis and a history of ingesting raw molluscs. Larvae obtained from naturally infected A. fulica were orally administered to Rattus norvegicus. The worms were collected from the pulmonary artery and brain, and were morphologically characterized and compared to the Japan isolate of A. cantonensis. Adult worms and infective L(3) larvae (PE isolate) recovered from A. fulica specimens were also analyzed by polymerase chain reaction and restriction fragment length polymorphism of ITS2 region from rDNA and compared to A. cantonensis (ES isolate), A. vasorum (MG isolate) and A. costaricensis (RS isolate). The large size of the spicules (greater than those observed in other species of Angiostrongylus) and the pattern of the bursal rays agree with the original species description by Chen (1935). Furthermore, the morphology of the PE isolate was similar to that of Japan isolate. The PCR-RFLP profiles obtained were distinctive among species and no variation in patterns was detected among adult individuals from A. cantonensis isolates from PE and ES. The importance of A. fulica as an intermediate host of eosinophilic menigoencepahlitis in Brazil is emphasized.
Asunto(s)
Angiostrongylus cantonensis/aislamiento & purificación , Caracoles/parasitología , Adulto , Angiostrongylus cantonensis/anatomía & histología , Angiostrongylus cantonensis/crecimiento & desarrollo , Angiostrongylus cantonensis/patogenicidad , Animales , Encéfalo/parasitología , Brasil , Niño , ADN de Helmintos/genética , ADN Ribosómico/genética , ADN Espaciador Ribosómico/genética , Femenino , Genotipo , Humanos , Estadios del Ciclo de Vida , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Arteria Pulmonar/parasitología , Ratas , Infecciones por Strongylida/parasitología , Infecciones por Strongylida/patologíaRESUMEN
Acid phosphatase activity (Gömori technique) in salivary gland cells was investigated in adult insects (males and females) of four species of triatomines: Triatoma infestans, Panstrongylus megistus, Rhodnius neglectus, and Rhodnius prolixus. Binucleated cells with bulky and polyploidy nuclei were detected, with acid phosphatase activity in the heterochromatin and nucleolus, which showed the most intense response. Thus, the activity of these phosphatases during rRNA molecule transcription, possibly in the nucleolar fibrillar center, is suggested. The difference in reactivity found among salivary glands is associated with the cellular metabolism of these regions and, probably, with the biosynthesis of their different secretions. This must be essential in maintaining the hematophagy of triatomines.
Asunto(s)
Fosfatasa Ácida/metabolismo , Núcleo Celular/enzimología , Glándulas Salivales/enzimología , Triatominae/enzimología , Animales , Femenino , Masculino , Glándulas Salivales/citologíaRESUMEN
Acid phosphatase activity (Gömori technique) in salivary gland cells was investigated in adult insects (males and females) of four species of triatomines: Triatoma infestans, Panstrongylus megistus, Rhodnius neglectus, and Rhodnius prolixus. Binucleated cells with bulky and polyploidy nuclei were detected, with acid phosphatase activity in the heterochromatin and nucleolus, which showed the most intense response. Thus, the activity of these phosphatases during rRNA molecule transcription, possibly in the nucleolar fibrillar center, is suggested. The difference in reactivity found among salivary glands is associated with the cellular metabolism of these regions and, probably, with the biosynthesis of their different secretions. This must be essential in maintaining the hematophagy of triatomines