The morphological study on the adrenal gland of African ostrich chicks

Post-hatching developmental changes in the adrenal gland of the Japanese quail (Coturnix coturnix japonica): Histological, immunohistochemical, and electron microscopic studies

The adrenal glands are paired abdominal endocrine organs vital to the bird's health. The present research aimed to provide a comprehensive examination of the histological, ultrastructural, and immunohistochemical investigations of the adrenal gland in Japanese quail during the post hatching period. The current study was performed on 21 healthy Japanese quail chicks at different post hatching periods. Our results showed the adrenal gland is surrounded by a connective tissue capsule, which consists of dense collagen fibers containing large blood vessels, chromaffin cells, autonomic ganglia, fibroblasts, and migrating Schwann cells. The zonation of the adrenal gland is composed of a subcapsular layer, a peripheral zone, and a central zone, which gets more pronounced with age. At the ultrastructural level, the interrenal cells take the steroid-secreting cells characters; they have varying amounts of lipid droplets and abundant mitochondria. Adrenal medullary chromaffin cells showed positive immunoreactivity to the NSE. With increasing age, the chromaffin tissue's Sox10 immunoreactivity increased. β-catenin is expressed within the plasmalemma and the cytoplasm of the interrenal and chromaffin cells and its reactivity increased with age, especially in the chromaffin cells. Our results indicate the adrenal gland undergoes significant morphological changes during the postnatal life. Overall, the postnatal period is an important time for the development and maturation of the adrenal glands.

Interrenal development and function in zebrafish

In this article we aim to provide an overview of the zebrafish interrenal development and function, as well as a review of its contribution to basic and translational research. A search of the PubMed database identified 41 relevant papers published over the last 20 years. Based on the common themes identified, we discuss the organogenesis of the interrenal gland and its functional development and we review what is known about the genes involved in zebrafish steroidogenesis. We also outline the consequences of specific defects in steroid biosynthesis, as revealed by evidence from genetically engineered zebrafish models, including cyp11a2, cyp21a2, hsd3b1, cyp11c1 and fdx1b deficiency. Finally, we summarise the impact of different chemicals and environmental factors on steroidogenesis. Our review highlights the utility of zebrafish as a research model for exploring important areas of basic science and human disease, especially in the current context of rapid technological progress in the field of Molecular Biology.

Morphological and histological studies of the adrenal gland in the Japanese quail (Coturnix japonica)

The adrenal gland is a vital endocrine gland that secretes many important hormones in everyday bird life. The adrenal gland of the Japanese quail is grossly located ventromedially the corresponding kidney and has a creamy to yellow color. The quail gland is surrounded by a capsule and contains some ganglionic cells, and the capsule is characterized by the presence of chromaffin cells. The adrenal gland is subdivided into three concentric zones: subcapsular, peripheral, and central. The parenchyma consists of interrenal tissue, chromaffin islets, and blood sinusoids. The interrenal cells contain lipid droplets, are arranged in cords, and rest on the basement membrane. Chromaffin cells are categorized as two types: epinephrine (E) and norepinephrine (NE) cells. These cells contain the granules, and are characterized by the presence of lipid droplets. In this study, the interrenal tissue was found to have a higher proportion of chromaffin cells in quail as compared with other birds, which is attributed to the fact that the Japanese quail is a migratory bird. Therefore, the present investigation aims to provide a detailed study on the adrenal gland in the Japanese quail to help physiologists understand the gland's function and the pathologist to determine the implications for the differential diagnosis of adrenal gland tumors. HIGHLIGHTS: The adrenal gland is subdivided into three concentric zones: subcapsular, peripheral, and central. The interrenal cells contain lipid droplets, are arranged in cords. Chromaffin cells are categorized as two types: epinephrine (E) and norepinephrine (NE) cells. These cells contain the granules, and are characterized by the presence of lipid droplets. The interrenal tissue was found to have a higher proportion of chromaffin cells in quail because it is a migratory bird.