Glomera aortica

Heart and great vessels. The glomera aortica, not visible, lie in front of and under the aortic arch (Arch of Aorta).

The glomera aortica ( singular glomus aorticum ; aortic body ) are irregularly distributed millimeter-sized structures in the area of ​​the aortic arch and the subclavian artery , which with the somewhat larger, paired glomera carotica above the point of division of the arteria carotis commonis and other glomera , for example on the larynx Defense against hypoxia , i.e. an insufficient supply of oxygen . This glomera is sometimes counted among the Paraganglia .

The glomera aortica consist of so-called envelope cells and main cells , as well as blood vessels and nerve fibers . The nerve fibers run mainly via the vagus nerve towards the brain. The main cells contain messenger substances such as acetylcholine , dopamine , serotonin and adenosine triphosphate stored in vesicles . They work as chemoreceptors . If the oxygen partial pressure of the blood falls when there is insufficient oxygen supply , if the carbon dioxide partial pressure rises or if the pH value falls , the cells are excited - and indeed depolarized - and release their messenger substances. The messenger substances in turn excite the nerve fibers of the glomera, and the brain counteracts the deficiency.

The glomera aortica are difficult to access and therefore less well known than the glomera carotica. The latter were identified as early as 1743, the glomera aortica not until 1906 and only approximately. The Belgian pharmacologists Jean-François Heymans and his son Corneille Heymans discovered their precise location and function in 1927. Today we know that its main cells react in a similar way to the main cells of the carotid glomer. If there is a lack of oxygen, it is possible that breathing is primarily stimulated via the glomera carotica, while the glomera aortica is primarily used to stimulate the heart; this would promote both oxygen uptake and oxygen transport.

literature

• Peter Böck: The Paraganglia. In: Handbook of Microscopic Human Anatomy Volume VI. Blood vessel and lymphatic system, internal secretory glands . Springer-Verlag , Berlin 1982, ISBN 3-540-10978-1 .
• Julius H. Comroe : The peripheral chemoreceptors. In: Wallace O. Fenn, Hermann Rahn (eds.): Handbook of Physiology Section 3: Respiration , Volume 1, pp. 557-583. American Physiological Society , Washington 1964.
• W. Sorrow: Paraganglia. In: Detlev Drenckhahn : Benninghoff - Drenckhahn - Anatomie. 16th edition. Volume 2, pp. 615-620. Elsevier Urban & Fischer , Munich 2004. ISBN 3-437-42350-9 .
• Nikol A. Piskuric, Colin A. Nurse: Effects of chemostimuli on [Ca ²⁺ ] _i responses of rat aortic body type I cells and endogenous local neurons: comparison with carotid body cells. In: The Journal of Physiology 590, 2012, pp. 2121-2135. doi : 10.1113 / jphysiol.2012.229468

Individual evidence

1. ↑ Böck 1982, p. 122.
2. ↑ J.-F. Heymans, C. Heymans: Sur les modifications directes et sur la régulation réflexe de l'activité du center respiratoire de la tête isolée du chien. In: Archives internationales de Pharmacodynamie et de Thérapie 33, 1927, pp. 273–372.
3. ↑ Piskuric and Nurse 2102.
4. ↑ Kummer 2004, p. 620.
5. ↑ Piskuric and Nurse 2012.