Ventral aorta

Both ventral aorta in the area between the fourth and third aortic arcs are converted into common carotid arteries, aa. carotides communes, and due to the above transformations of the proximal ventral aorta, the right common carotid artery turns out to be extending from the brachiocephalic trunk, and the left one directly from the arcus aortae. In the future, the ventral aorta is transformed into the external carotid artery, aa. carotides externae.

The third pair of aortic arches and the dorsal aorta in the segment from the third to the first branchial arch develop into the internal carotid arteries, aa. carotides internae, bbm, and it is explained that the internal carotid arteries lie more laterally in the adult than the external. The second pair of aortic arches turns into aa. linguales et pharyngeae, and the first pair – in the maxillary, facial and temporal arteries. In violation of the normal course of development, various anomalies arise.

From the dorsal aorta, a series of small paired vessels arises, running in the dorsal direction on both sides of the neural tube. Since these vessels diverge at regular intervals into the loose mesenchymal tissue located between the somites, they are called the dorsal intersegmental arteries. In the neck, on both sides of the body, they are joined early by a series of anastomoses, forming longitudinal vessels – the vertebral arteries.

At the level of the 6th, 7th and 8th cervical intersegmental arteries, the kidneys of the upper extremities are laid. One of the arteries, usually the 7th, grows into the upper limb and increases with the development of the arm, forming the distal subclavian artery (its proximal part develops, as already indicated, on the right of the 4th aortic arch, on the left grows from the left dorsal aorta, which the 7th intersegmental arteries connect).

Subsequently, the cervical intersegmental arteries are obliterated, as a result of which the vertebral arteries are derived from the subclavian.

Thoracic and lumbar intersegmental arteries give rise to aa. intercostales posteriores and aa. lumbales.

The abdominal visceral arteries develop partly from aa. omphalomesentericae (yolk-mesenteric circulation) and part of the aorta.

Arteries of the limbs were originally laid along the nerve trunks in the form of loops.

Some of these loops (along the n. Femoralis) develop into the main arteries of the extremities, others (along the n. Medianus, n. Ischiadicus) remain companions of nerves.