Paraganglia

Paraganglia - specific organs originating from the rudiments of the autonomic nervous system, some of these bodies are involved in the internal secretion, and others in chemoreception. There are chromaffin paraganglia related to adrenal system, the cells which produce adrenaline (after fixing the bichromate become yellow color), and necromania related to chemoreceptors. Adrenal system includes the brain substance napochechnikov (see), which is the largest chromaffin paraganglia, and free chromaffin cells. The small paraganglia are locations sympathetic plexus. The abdominal aorta lies abdominal aortic paraganglia, which is particularly developed in children. To necromorphism paraganglia include carotid, jugular, aortic-pulmonary glomus and other Cells they are in close contact with blood vessels, delegate of irritation to the nerve endings. Cm. also Glomus, Carotid iron.

Paraganglia (paraganglia) - special bodies, some of which date back to the adrenal, or chromaffin, others - to the chemoreceptor system. Both paraganglia develop from neiroendokrinnoi bookmarks. Adrenal system includes the brain substance napochechnikov (see), available chromaffin cells and cell clusters in the sympathetic ganglia. Physiological role of adrenal system is determined by highly active secretion of hormones group of catecholamines. Fabric adrenal system formed large prismatic cells connected in anastomosis bands, limited on the one hand of blood, on the other venous sinuses. The cytoplasm contains a large number of secretory granules and in contact with axoneme sympathetic nerves.
Chemoreceptor bodies presents nodular lumps-newromfilename P. (Fig) and klausami (see). Necromania paraganglia located on the forks of arterial trunks, in the walls of the veins, in the course of the branches of the parasympathetic nerves and tissue nodes; their sizes range from microscopic to 0.5 cm in diameter.
To necromorphism P. include drum, carotid, jugular, aortic-pulmonary nodules, glomus of the stomach, skin. A functional unit on, are retsepturno transforming cells closely in contact with blood vessels and transferring appropriate irritation of the nervous devices. Receptor, the so-called light or epithelioid cells surround the blood vessels in the form of clutches, composed in bands or cell, closely adjacent to anastomosis blood vessels. For reprompting paraganglia typically arterio-blood circulation, which is combined with arteriovenous; leading and lateral vessels are vessels closing type. In the cytoplasm of the principal cells discovered serotonin, lipochrome, various enzymes and cholinesterase. Chemoreceptors (see Receptors) highly sensitive to hypoxia and take part in regulation of the constancy of the level of oxygen in the blood. Excitation of chemoreceptors in hypoxia causes a reflex shortness of breath, high blood pressure and decreased spleen, increase the total amount of oxygen the blood.
Cm. also Carotid iron.

Necromania paraganglia gussarova node person.