Gastroesophageal tube of the Iguana iguana : descricao histologica, histoquimica e analise imunohistoquimica de celulas 5-HT e SS

• Published in: Brazilian journal of biology 2023-01, Vol.83
• Main Authors: Serra-Campos, A.O, Abreu, A.N.G., Jr, Nascimento, A.A, Abidu-Figueiredo, M, Lima, M.S.C.S, Machado-Santos, C
• Format: Article
• Language: English
• ISSN: 1519-6984
• DOI: 10.1590/1519-6984.242086

The work aims were to describe the histological and histochemical structure of the gastroesophageal tube of Iguana iguana and verify the occurrence and distribution of immunoreactive serotonin (5-HT) and somatostatin (SS) cells. Fragments of the gastrointestinal tract (GIT) of five iguanas were which underwent standard histological and immunohistochemistry technique. Immunoreactive cells for 5-HT and SS were quantified using the STEPanizer. The oesophagus has ciliated columnar pseudostratified epithelium with staining Alcian blue (AB) + and goblet cells highly reactive to periodic acid Schiff (PAS). In the cervical oesophagus, the numerical density of 5-HT cells per unit area (QA [5-HT cells]/[micro][m.sup.2]) was 4.6 * [10.sup.-2] [+ or -] 2.0 and celomatic oesophagus presented QA = 4.0 * [10.sup.-2] [+ or -] 1.0. The epithelium of the stomach is simple columnar, PAS and AB +. The cranial and middle regions of the stomach presented (QA [5-HT cells]/[micro][m.sup.2]) = 6.18 * [10.sup.-2] [+ or -] 3.2 and the caudal region, QA = 0.6 * [10.sup.-2] [+ or -] 0.2. The SS cells were only observed in the caudal stomach, with numerical density (QA [SS cells]/[micro][m.sup.2]) = 1.4 * [10.sup.-2] [+ or -] 0.9 In I. iguana, variation was observed in terms of the distribution of mucus secretions and the pattern of occurrence of serotonin and somatostatin-secreting enteroendocrine cells in the TGI, which possibly will result in an interspecific adaptive response. Keywords: serotonin, somatostatin, stomach-oesophagus, morphology, reptilian. Os objetivos do trabalho foram descrever a estrutura histologica e histoquimica do tubo gastroesofagico da Iguana iguana e verificar a ocorrencia e distribuicao de celulas serotonina (5-HT) e somatostatina (SS) imunorreativas. Fragmentos do trato gastrointestinal (TGI) de cinco iguanas foram submetidos a tecnica histologica e imunohistoquimica padrao. As celulas imunorreativas para 5-HT e SS foram quantificadas usando o STEPanizer. O esofago apresenta epitelio pseudoestratificado colunar ciliado Alcian blue (AB) positivo, com celulas caliciformes altamente reativas ao acido periodico de Schiff (PAS). No esofago cervical, a densidade numerica de celulas 5-HT por unidade de area (QA [celulas 5-HT] / [micro][m.sup.2]) foi de 4.6 * [10.sup.-2] [+ or -] 2.0 e o esofago celomatico apresentou QA = 4.0 * [10.sup.-2] [+ or -] 1.0. O epitelio do estomago e colunar simples, PAS e AB positivo. As regioes cranial e media do estomago apresentaram