Adrenal glands of Spix's yellow-toothed cavy (Galea spixii, Wagler, 1831): morphological and morphometric aspects

Abstract

Considering the physiological importance and need of greater morphophysiological knowledge of adrenal glands, the aims of present study were compare the morphometric data between left and right adrenal of male and female; perform a histological, scanning and transmission electron microscopy study showing tissue constitution of glands; finally, in order to define the presence and correct site of the cytochrome P450c17 expression in adrenal glands, immunohistochemical study of this enzyme was performed in 18 adrenal glands (right n=9 and left n=9) of nine adult Galea spixii (four males and five females). Right adrenal was more cranially positioned than left adrenal; dimensions (weight, length and width) of right adrenal was larger than left adrenal; no differences between male and female body and adrenal measurements were found; the morphology of cells and different amounts of lipid droplets may be related to the different demands of steroid hormones production, related to each zone of the adrenal cortex; and, the cytochrome P450c17 immunolocalization in fasciculate and reticular zone may be related with synthesis of 17-hydroxy-pregnenolone, 17-hydroxy-progesterone, dehydroepiandrosterone or androstenedione.Keywords: adrenal cortex, adrenal medulla, CYP, steroidogenic enzymes, wild rodents. Glândulas adrenais de preás (Galea spixii, Wagler, 1831):aspectos morfológicos e morfométricos ResumoConsiderando a importância fisiológica e a necessidade de melhor conhecimento morfofisiológico das glândulas adrenais, os objetivos do presente estudo foram comparar dados morfométricos entre adrenais direitas e esquerdas de machos e fêmeas; realizar estudos histológicos e microscopia eletrônica de varredura e transmissão revelando a constituição tecidual das glândulas; finalmente, foi realizado estudo imunohistoquímico com objetivo de definir a presença e correto sítio de expressão da citocromo P450c17 nas glândulas adrenais em 18 glândulas adrenais (direita n=9 e esquerda n=9) de nove Galea spixii adultos (quatro machos e cinco fêmeas). A glândula adrenal direita estava posicionada mais cranialmente que a adrenal esquerda; as dimensões (peso, comprimento e largura) da glândula adrenal direita foram maiores que as da esquerda; não houve diferença entre as medidas corpóreas e das adrenais entre machos e fêmeas; a morfologia das células e diferentes quantidades de gotículas lipídicas podem estar relacionadas a diferentes demandas na produção de hormônios esteroides relacionados a cada zona do córtex adrenal; e, a imunolocalização da citocromo P450 na zona fasciculada e reticular pode estar relacionado com a síntese de 17-hidroxi-pregnenolona, 17-hidroxi-progesterona, dehidroepiandrosterona ou androstenediona.Palavras-chave: córtex adrenal, medula adrenal, CYP17, enzimas esteroidogênicas, roedores silvestres.

Morphology of the adrenal glands of giant anteater (Myrmecophaga tridactyla, Linnaeus, 1758) of wild life

“…Additionally, measurements were statistically higher (p<0.05) in the right glands, except for thickness. These results differ from studies by Machado et al (2002) in Myocastor coypus and Santos et al (2016) in Galea spixii. In this study, the authors observed asymmetry between the right and left glands.…”

“…These characteristics follow the topographic location described in other wild mammals such as rodents Lagostomus maximus (RIBES, 1999), Myocastor coypus (MACHADO et al, 2002;CULAU et al, 2008), Dasyprocta agouti (NEVES et al, 2007), Cavia porcellus (COOPER; SCHILLER, 1975) and Galea spixii (SANTOS et al, 2016), and domestic animals such as dogs, cats and horses (REECE et al, 2005). Morphology of the adrenal glands… SANTOS, A. C. et al…”

“…In this study, the authors observed asymmetry between the right and left glands. The right adrenal had triangular shape and smaller volume compared with the left gland, which had elongated shape in Galea spixii (SANTOS et al, 2016).…”

“…It has as main characteristic, the presence of cells arranged in oval groups very attached and with reduced intracellular spaces, similarly to rats (CHANG et al, 2011), Galea spixii (SANTOS et al, 2016) and Gerbilus tarabuli (SAADI;LEBAILI, 2012); the second layer is the fasciculata, characterized by columns of vacuolated cells as in rats (CHANG et al, 2011. ) and Galea spixii (SANTOS et al, 2016.…”

“…In mammals, each adrenal gland is composed of two structures: the cortex, which is originated from embryonic mesoderm and the medulla, which is originated from embryonic neurectoderm. Each part of the adrenal gland has different cell types: the cortex cells produce mineralocorticoid, glucocorticoids and sexual steroid hormones (SANTOS et al, 2016) while in the medulla, chromaffin cells produce catecholamine and neuropeptides (KEMPNÁ;FLÜCK, 2008;QIU et al, 2012).…”