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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a series of endocrine glands of vertebrate animals and man that are composed of chromaffin (adrenal) tissue and that secrete adrenaline (epinephrine), noradrenaline (norepinephrine), and possibly other catecholamines into the blood. In man and mammals paraganglia include very small nodules as well as large encapsulated, lobulated aggregates, which have an organ structure. The largest paraganglia are the medullary portions of the adrenal glands; substantially smaller are the carotid paraganglion and the paraganglia located near the heart and aorta. The components of paraganglia are secretory cells, of at least two types, and auxiliary cells, which are enclosed in connective-tissue stroma. The hormone is stored in cytoplasmic granules. Upon excitation (depolarization) of the cell membrane, it is secreted by evacuation of the granule contents into the extracellular medium. The biochemical and pharmacological characteristics of the secretory cells of paraganglia are similar to those of some neurons, especially sympathetic ones, in which noradrenaline is the mediator and which, in the opinion of a number of scientists, share a common embryonic origin with paraganglial cells. The auxiliary, or lining, cells cytologically resemble neuroglia. A unique feature of paraganglia is that their secretory cells are directly innervated, that is, they are innervated by efferent (motor) nerve endings. Functionally and genetically, paraganglia are a single system that cannot be divided into chromaffin (“sympathetic”) and nonchromaffin (“parasympathetic”) parts. The erroneous distinction of nonchromaffin paraganglia led to denial of their secretory function and to the notion that the carotid paraganglion, for example, functions as an organ of chemical sense. It is now established that all paraganglia have a single type of chemistry, which is adrenaline-related, and that the innervation of paraganglial secretory cells is efferent.


Smitten, N. A. Simpato-adrenalovaia sistema v filo- i ontogeneze pozvonochnykh. Moscow, 1972.
Coupland, R. E. The Natural History of the Chromaffin Cell. London, 1965.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Paragangliomas are tumours that arise from neural crestderived endocrine cells or organs, known as paraganglia. These paraganglia can be divided into two groups
These slow-growing tumors emanate from either of the two paired paraganglia - the superior or inferior (1, 3).
Pheochromocytoma (PHEO; MIM #171300) is a rare neuroendocrine tumor of chromaffin cells originating in the adrenal medulla, whereas paragangliomas (PGLs; MIM #168000) are even rarer tumors arising in the paraganglia along the parasympathetic and sympathetic chains [1].
Pheochromocytoma and paraganglioma are relatively uncommon tumors of neuroendocrine origin that arise from neural crest-derived chromaffin cells of the adrenal medulla and sympathoadrenal and parasympathetic paraganglia, respectively.
Paragangliomas are rare neuroendocrine tumors that arise from the extra-adrenal autonomic paraganglia. These are small organs consisting mainly of neuroendocrine cells that are derived from the embryonic neural crest and have the ability to secrete catecholamines [1].
Paragangliomas arise from the paraganglia, which are small groups of neuroendocrine cells stemming from autonomic nervous system ganglia.
(2) Paraganglioma is a kind of tumour that arises from extraadrenal paraganglia and consists of specialized neural crestderived cells.
Most of these are catecholamine-secreting tumors and primarily located in the abdomen (more rarely in the chest) in the extraadrenal paraganglia, whereas the remainder are generally non-catecholamine secreting and mostly located in the head and neck paraganglia (5).
Mediastinal paragangliomas are hypervascular tumours and many of them invade or firmly adhere to the adjacent mediastinal organs such as heart, great vessels, trachea and the spine.1 Mediastinal paragangliomas are predominantly concentrated in two locations; the aorticosympathetic paraganglia of the posterior mediastinum or the autonomic ganglia in the superior and middle mediastinum.6 Aorticopulmonary tumours tend to occur in patients with a mean age of 49 years with no gender preference and only 3% of these secrete catecholamines.
The third and final part of the book is made up of various real-world cases, including adrenal and paraganglia diagnosis, anterior mediastinal mass diagnosis, appendix diagnosis, and several other examples.
Tympanic paragangliomas are neuroendocrine neoplasms located in the middle ear and arising from chromaffin cells of the parasympathetic paraganglia. (1) Patients classically present with pulsatile tinnitus and a red mass medial to the tympanic membrane.