Arctostaphylos uva-ursi

Series of six paired embryological vascular structures

The aortic arches are a series of six paired embryological vascular structures that give rise to several major arteries in the adult. These arches are part of the pharyngeal arches and are crucial in the development of the circulatory system in vertebrates. In humans, these structures are transient and undergo significant remodeling to form the great arteries of the heart.

Development

The aortic arches develop from the aortic sac, which is an extension of the truncus arteriosus. Each arch is associated with a corresponding pharyngeal arch and is initially symmetrical on both sides of the embryo. As development progresses, these arches undergo complex transformations, with some regressing and others forming the major arteries of the body.

First Aortic Arch

The first aortic arch largely regresses, but it contributes to the formation of the maxillary artery, which supplies the deep structures of the face.

Second Aortic Arch

The second aortic arch also regresses significantly, with remnants forming the stapedial artery in the embryo, which is not present in adults.

Third Aortic Arch

The third aortic arch is crucial as it forms the common carotid arteries and the proximal portion of the internal carotid arteries.

Fourth Aortic Arch

The fourth aortic arch has different fates on the left and right sides. On the left, it forms part of the aortic arch itself, while on the right, it contributes to the formation of the right subclavian artery.

Fifth Aortic Arch

The fifth aortic arch is either rudimentary or absent in humans and does not contribute to any major adult structures.

Sixth Aortic Arch

The sixth aortic arch is also known as the pulmonary arch. On the left side, it forms the ductus arteriosus and part of the pulmonary arteries. On the right side, it contributes to the formation of the right pulmonary artery.

Clinical Significance

Abnormal development of the aortic arches can lead to congenital anomalies such as coarctation of the aorta, interrupted aortic arch, and vascular rings. These conditions can have significant clinical implications, often requiring surgical intervention.

Related pages

• Pharyngeal arches
• Circulatory system
• Embryology
• Congenital heart defect

Gallery

• 
  Diagram of the aortic arches in a human embryo.
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  Illustration showing the transformation of the aortic arches.
• 
  Development of the aortic arches and their derivatives.

Arctostaphylos uva-ursi

• File:Arctostaphylos uva-ursi 25924.JPG