Estudo quantitativo e qualitativo dos plexos de Auerbach e Meissner do esôfago de cães inoculados com o Trypanosoma cruzi

Abstract

Foi realizado um estudo quantitativo e qualitativo dos plexos deAndrade caracterizou bem a fase aguda e a forma indeterminada da cardiopatia chagásica no cão1 . Lana inoculando a cepa Be78 em cães caracterizou m uito bem a card io p atia chagásica crônica fibrosame, com quadro clínico e eletrocardiográfico muito semelhante a forma cardíaca humana". Pelo que sabemos, até o m o m en to , não se d o cu m en to u claramente a forma digestiva (megaesôfago e megacólon) experimental. Também nao se tem notícias de estudos sistematizados dos neurônios dos plexos de Auerbach e Meissner do esôfago na trip a n o so m ía se cruzi experimental. Por estas razões realizamos o presente trab a lh o , no p re s su p o s to de encontrar prováveis lesões neuronais do esôfago na infecção chagásica experimental canina.

Morphometry of submucous and myenteric esophagic plexus of dogs experimentally reinfected with Trypanosoma cruzi

“…These data are in accordance with Caliari et al (1996) that, analyzing a greater number of esophageal sections of dogs sacrificed in the acute phase, also did not find denervation and only identified rare neurons in the submucosal plexus, suggesting that this plexus has a small number of neurons. In the present study, no denervation was observed maybe because the strains SC-1 and 147 have little destructive action on the myenteric plexus.…”

“…The denervation absence observed in the esophagus of the dogs, agree with results of Caliari et al (1996), Santos (1998) and Santos et al (1998), that have studied the acute phase of Chagas disease in dogs. However, our findings of neurons size between chagasic and non-chagasic dogs differ from Santos (1998).…”

“…Köeberle (1957) found dogs with megaesophagus and/or megacolon, however, the animals were naturally infected by Trypanosoma cruzi and the author did not describe how long the dogs have been infected. Two systematic studies of esophagus submucous nerve cells and myenteric plexuses in experimental Chagas disease in dogs were made (Caliari et al 1996, Santos 1998, both in the acute phase of the disease, where no denervation was found. In this work, we analyzed the morphometry of the esophagus, from dogs experimentally infected and/or reinfected with T. cruzi, to evaluate causal denervation and/or hypertrophy in the intramural plexuses of this organ as well as the possible influence of reinfection in this process.…”

Myenteric plexus is differentially affected by infection with distinct Trypanosoma cruzi strains in Beagle dogs

“…Sections were viewed with a 40X objective and images were digitised by Leica DFC340FX microcamera associated with Leica DM5000B microscopy; all images were analysed using the image processing and analysis software Leica Qwin V3 at Multiuser Laboratory of Center for Research in Biological Sciences of UFOP. The inflammatory process was assessed by cell nuclei quantification in the submucous and muscular layers in 20 random images (fields) covering a total area equal to 1.5 × 10 6 µm 2 and the difference (p < 0.05) between the number of cell nuclei present in the animals infected with T. cruzi and that observed in NI animals (cut-off) determined the number of inflammatory cells ( Caliari et al 1996 , Maltos et al 2004 ). The images number was determined by stability statistical test draw at random replacement.…”

“…Given the scarcity of experimental models to study digestive tract changes in ChD and similarities in disease progression in a canine model ( Canis familiaris ) ( de Lana et al 1988 , 1992 , Caliari et al 1996 , Machado et al 2001 ), as well as the potential role of ENS components in the development of the digestive form of ChD, this study evaluated the profile of changes that occurred in the oesophagus and colon of Beagle dogs after infection with two morphologically distinct T. cruzi subpopulations belonging to the discrete typing unit (DTU) TcII.…”