The ventrolateral medulla, part of the

medulla oblongata The medulla oblongata or simply medulla is a long stem-like structure which makes up the lower part of the brainstem. It is anterior and partially inferior to the cerebellum. It is a cone-shaped neuronal mass responsible for autonomic (involun ...

of the

brainstem The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is conti ...

, plays a major role in regulating

arterial blood pressure Blood pressure (BP) is the pressure of circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term "blood pressure" r ...

and

breathing Breathing (spiration or ventilation) is the rhythmical process of moving air into ( inhalation) and out of ( exhalation) the lungs to facilitate gas exchange with the internal environment, mostly to flush out carbon dioxide and bring in oxy ...

. It regulates blood pressure by regulating the activity of the sympathetic nerves that target the heart and peripheral

blood vessel Blood vessels are the tubular structures of a circulatory system that transport blood throughout many Animal, animals’ bodies. Blood vessels transport blood cells, nutrients, and oxygen to most of the Tissue (biology), tissues of a Body (bi ...

s. The ventrolateral medulla consists of a

rostral ventrolateral medulla The rostral ventrolateral medulla (RVLM), also known as the pressor area of the medulla, is a part of the ventrolateral medulla in the brainstem responsible for basal and reflex control of sympathetic activity associated with cardiovascular fun ...

(RVLM) and a caudal ventrolateral medulla (CVLM). Neurons in the RVLM project directly to preganglionic neurons in the

spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue that extends from the medulla oblongata in the lower brainstem to the lumbar region of the vertebral column (backbone) of vertebrate animals. The center of the spinal c ...

and maintain tonic activity in the sympathetic vasomotor nerves. This activity is inhibited by

GABA GABA (gamma-aminobutyric acid, γ-aminobutyric acid) is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. GA ...

output from the CVLM.

References

Sympathetic nervous system Reflexes Medulla oblongata Cardiovascular physiology {{neuroanatomy-stub