Histologia e histoquímica do tubo digestório de Phrynops geoffroanus (Testudines, Chelidae)

Abstract

. Juiz de Fora, Minas Gerais, Brasil. bernadete.sousa@ufjf.edu.br. RESUMOPhrynops geoffroanus é o quelônio onívoro com mais ampla distribuição geográfica na América do Sul. Este trabalho descreve a histologia e histoquímica do tubo digestório desta espécie, relacionando as características dos órgãos com seu hábito alimentar. O esôfago, estômago e intestino de quatro espécimes foram fixados em formol 10% e incluídos em parafina por técnica histológica de rotina. Depois, cortes de 5 μm de espessura foram corados com hematoxilina-eosina (HE), ácido periódico de Schiff (PAS) e alcian blue (AB) pH 0.4 e 2.5. O tubo é formado pelas camadas mucosa, submucosa, muscular e adventícia ou serosa. A mucosa do esôfago e do estômago é revestida pelo epitélio simples cilíndrico com células mucossecretoras, onde estão inseridas glândulas intraepiteliais na porção do esôfago e fossetas gástricas desembocando em glândulas no estômago. O estômago divide-se em anterior, médio e posterior, de acordo com a profundidade das fossetas e a concentração de glândulas gástricas. O intestino é revestido pelo epitélio simples cilíndrico com borda estriada e células caliciformes e divide-se em anterior e posterior, de acordo com o padrão de dobramentos da mucosa e o número de células caliciformes. Reatividade ao PAS e AB é observada em todo o tubo. Fibras musculares lisas estão presentes na camada mucosa de todos os segmentos. A camada muscular é formada por duas subcamadas de músculo liso, exceto na porção posterior do estômago. Este estudo ajudará no entendimento da fisiologia digestiva da espécie investigada e fornecerá dados para análises comparativas com outros quelônios. PALAVRAS CHAVES: Réptil, esôfago, estômago, intestino, células mucossecretoras. Histology and histochemistry of the digestive tract of Phrynops geoffroanus (Testudines, Chelidae)ABSTRACT Phrynops geoffroanus is the omnivorous chelonian with widest geographical distribution in South America. This work describes the histology and histochemistry of the digestive tube of this species, to relate the characteristics of these organs to the species' eating habit. The esophagus, stomach and intestine of four specimens were fixed in 10% formal and embedded in paraffin by routine histological techniques. Afterwards, 5-μm sections were stained with hematoxylin-eosin (HE), periodic acid-Schiff (PAS) and alcian blue (AB) pH 0.4 and 2.5. The tube is formed by the mucosa, submucosa, muscular and adventitia or serosa layers. The mucosa layer of the esophagus and stomach is lined with a simple cylindrical epithelium with mucus-secreting cells, where are intraepithelial glands inserted in the portion of the esophagus and gastric fossettes emptying into glands in the stomach. The stomach is divided into an anterior, middle and posterior region, according to the depth of the fossettes and the concentration of gastric glands. The intestine is lined by a simple cylindrical epithelium with striated boundaries and goblet cells and is divided into an anterior and posterior regions, according to th...

Effect of 60 and 90 days of isotretinoin treatment on the structure of the small intestine mucosa in young male Wistar rats

“…In the ileum, we had an increase in PAS+AB+ goblet cells. This result indicates a potential of microbiota maintained by PAS+AB+goblet cell secretion (Frankel et al , 1995 ; Deplancke & Gaskins, 2001 ; Azevedo et al, 2007 ; Vieira-Lopes et al, 2014 ). The difference found in these proportions is related to the treatment, considering the reversal observed after its interruption, but the alteration is not sufficient to cause loss of the small intestine function.…”

“…In addition, it serves as a lubricant for the passage of solids and as a barrier to antigens, bacteria and viruses (Shirazi et al , 2000 ; Walker & Talley, 2011 ; Chawla et al , 2013 ; Kim & Khan, 2013 ). The diet and the use of drugs can alter the distribution and frequency of goblet cells and it is related to the maintenance of bacterial translocation and microbiota (Frankel et al , 1995 ; Deplancke & Gaskins, 2001 ; Azevedo et al, 2007 ; Vieira-Lopes et al, 2014 ). The modifications concerning goblet cells were concentrated in the duodenum and ileum and the results are interesting, considering the typical goblet cell type in both regions.…”

Morphological characterization of the digestive tube of hawksbill sea turtle (Eretmochelys imbricata) hatchlings

“…Calais Junior et al (2016), when describing the esophagus morphology of C. mydas , observed the presence of PAS-positive mucus-producing glands located in the gastroesophageal region mucosa. Vieira-Lopes et al (2014) also verified the presence of well-defined glands interspersed in the mucosal epithelium of the esophagus on some freshwater turtles, such as Phrynops geoffroanus , formed by clear cells in a semicircular arrangement, while Magalhães et al (2014) reported the presence of mucus-producing superficial cells throughout the esophagus when studying the morphology of the DT of freshwater turtles belonging to the Podocnemididae family, forming a continuous layer of secretory cells occupying the entire apical region, stained positively with PAS, more intense in the posterior portion. In addition to these mucus-producing cells, the authors also verified the presence of some goblet cells irregularly distributed among the columnar cells in the epithelium but did not observe esophageal glands.…”

Segurança do tratamento com isotretinoína mensurado pelos parâmetros de estresse oxidativo, estrutura e ultraestrutura do fígado e intestino delgado de ratos Wistar machos

“…Mucins are likely to be the first molecules that invading pathogens interact with at the cell surface and thus, can limit binding to other glycoproteins and neutralize the pathogen (30)(31)(32)(33). The diet and the use of drugs can alter the distribution and frequency of goblet cells and it is related to the maintenance of bacterial translocation and microbiota (34)(35)(36)(37). The modifications concerning goblet cells were concentrated in the duodenum and ileum and the results are so interesting considering the typical goblet cell type in both regions.…”

“…The modifications concerning goblet cells were concentrated in the duodenum and ileum and the results are so interesting considering the typical goblet cell type in both regions. In duodenum the tendency of increase in PAS+ cell during the treatment and a decrease of the same cell after the treatment interruption indicates a potential of bolus hydration, linked to this type of mucin (34)(35)(36)(37).…”