Rostral ventromedial medulla

Not to be confused with Ventromedial nucleus of the hypothalamus.
Rostral ventromedial medulla
RVM is labeled 5 in red at the bottom
Details
Identifiers
LatinNucleus ventromedialis
NeuroNames2000
Anatomical terms of neuroanatomy

The rostral ventromedial medulla (RVM), or ventromedial nucleus of the spinal cord,[1][2] is a group of neurons located close to the midline on the floor of the medulla oblongata. The rostral ventromedial medulla sends descending inhibitory and excitatory fibers to the dorsal horn spinal cord neurons.[3] There are 3 categories of neurons in the RVM: on-cells, off-cells, and neutral cells. They are characterized by their response to nociceptive input. Off-cells show a transitory decrease in firing rate right before a nociceptive reflex, and are theorized to be inhibitory.[3] Activation of off-cells, either by morphine or by any other means, results in antinociception.[4] On-cells show a burst of activity immediately preceding nociceptive input, and are theorized to be contributing to the excitatory drive. Neutral cells show no response to nociceptive input.[3]

The rostral ventromedial medulla is also essential in the regulation of arterial pressure.[5]

  1. ^ Noback CR, Harting JK (1971). "Cytoarchitectural Organization of the Gray Matter of the Spinal Cord". Spinal Cord (Spinal Medulla): Primatologia. Karger Medical and Scientific Publishers. p. 2/14. ISBN 3805512058. Retrieved 11 August 2015.
  2. ^ ancil-2000 at NeuroNames
  3. ^ a b c Urban, M.O. (July 1999). "Supraspinal contributions to hyperalgesia". PNAS. 96 (14): 7687–7692. Bibcode:1999PNAS...96.7687U. doi:10.1073/pnas.96.14.7687. PMC 33602. PMID 10393881.
  4. ^ Morgan, Michael (November 2008). "Periaqueductal Gray neurons project to spinally projecting GABAergic neurons in the rostral ventromedial medulla". Pain. 140 (2): 376–386. doi:10.1016/j.pain.2008.09.009. PMC 2704017. PMID 18926635.
  5. ^ Madden, CJ; Sved, AF (October 2003). "Rostral ventrolateral medulla C1 neurons and cardiovascular regulation". Cellular and Molecular Neurobiology. 23 (4–5): 739–49. doi:10.1023/a:1025000919468. PMID 14514028.