The brain centers involved in cardiovascular regulation are the medullary sympathetic center (vasomotor center), the medullary parasympathetic center (cardio inhibitory center) and the medullary relay station for cardio respiratory afferents.

The spinal sympathetic center is located in the intermediolateral horn of the spinal cord (T1 – L2). It has two parts: the pressor area, containing the intermediolateral (IML) cells from which the
sympathetic fibers actually originate, and the depressor area located a little medially containing the intermediomedial (IMM) cells that inhibit the pressor area.

The medullary sympathetic center is better known as the vaso­motor center. It controls the output of the spinal sympathetic center. It has two parts: the pressor area located in the rostral ventrolateral medulla (RVLM) which increases the spinal sympa­thetic output, and the depressor area, located in the caudal ven­trolateral medulla (CVLM) which reduces the spinal sympathetic output. The medullary parasympathetic center gives rise to the vagal parasympathetic fibers to the heart. It was earlier called the cardio inhibitory center, and now called by its specific name nucleus ambiguous.

The medullary relay station for all cardio respiratory afferents is the nucleus of tractus solitarius (NTS). All peripheral afferents – bar receptors and chemoreceptors – end here. The afferents release the excitatory neurotransmitter glutamate. Cells of the NTS in turn relay the information to other centers that control parasympathetic and sympathetic output.