The so-called ligamentum arteriosum is innervated

Area of Science:

• Cardiovascular Biology
• Neuroscience
• Developmental Biology

Background:

• The ductus arteriosus is a fetal vessel that bypasses the lungs.
• Postnatally, it transforms into the ligamentum arteriosum (LA).
• Innervation of the ductus arteriosus is known, but its persistence in the LA is unclear.

Purpose of the Study:

• To investigate whether the ligamentum arteriosum retains innervation after birth.
• To characterize the nature of this innervation in humans and animal models.

Main Methods:

• Double-immunofluorescence labeling using neuronal markers (PGP 9.5) and smooth muscle markers (Smooth muscle actin).
• Transmission Electron Microscopy (TEM) on mouse LA samples.
• Analysis of human, pig, and mouse LA tissues.

Main Results:

• Extensive innervation of the ligamentum arteriosum was confirmed in mice, pigs, and senescent humans.
• Immunolabeling showed intense neuronal marker presence.
• TEM revealed nerve terminals close to smooth muscle cells, closer than typically seen in elastic arteries.

Conclusions:

• The ligamentum arteriosum is innervated, similar to the fetal ductus arteriosus.
• This innervation may influence vessel compliance and the local microenvironment.
• Further research into the neurochemistry of LA innervation is warranted.