The nucleus paragigantocellularis (nPGi) is a part of the

brain The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head ( cephalization), usually near organs for special ...

, located in the rostral ventral medulla. It is a key

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 ...

region involved in the expression of cardiovascular and respiratory changes that occur following sympathetic activation. The nPGi is one of two major afferents of the

locus coeruleus The locus coeruleus () (LC), also spelled locus caeruleus or locus ceruleus, is a nucleus in the pons of the brainstem involved with physiological responses to stress and panic. It is a part of the reticular activating system. The locus coer ...

(LC), and sends collateral projections to the LC and to the

nucleus of the solitary tract In the human brainstem, the solitary nucleus, also called nucleus of the solitary tract, nucleus solitarius, and nucleus tractus solitarii, (SN or NTS) is a series of purely sensory Nucleus (neuroanatomy), nuclei (clusters of nerve cell bodies) for ...

(NTS). Neurons in this region have also been associated with analgesia processes. Consistent with this, PGi neurons have widespread distributions to brain areas that are important for controlling autonomic activity and

nociception Nociception (also nocioception, from Latin ''nocere'' 'to harm or hurt') is the sensory nervous system's process of encoding noxious stimuli. It deals with a series of events and processes required for an organism to receive a painful stimulus, ...

References

{{Neuroanatomy-stub Brainstem