The roles of sodium channels in nociception:
Implications for mechanisms of pain

by
Cummins TR, Sheets PL, Waxman SG.
Department of Pharmacology and Toxicology,
Stark Neurosciences Research Institute,
Indiana University School of Medicine,
Indianapolis, IN 46202, United States.
trcummin@iupui.edu
Pain. 2007 Oct;131(3):243-57.


ABSTRACT

Understanding the role of voltage-gated sodium channels in nociception may provide important insights into pain mechanisms. Voltage-gated sodium channels are critically important for electrogenesis and nerve impulse conduction, and a target for important clinically relevant analgesics such as lidocaine. Furthermore, within the last decade studies have shown that certain sodium channel isoforms are predominantly expressed in peripheral sensory neurons associated with pain sensation, and that the expression and functional properties of voltage-gated sodium channels in peripheral sensory neurons can be dynamically regulated following axonal injury or peripheral inflammation. These data suggest that specific voltage-gated sodium channels may play crucial roles in nociception. Experiments with transgenic mice lines have clearly implicated Na(v)1.7, Na(v)1.8 and Na(v)1.9 in inflammatory, and possibly neuropathic, pain. However the most convincing and perhaps most exciting results regarding the role of voltage-gated sodium channels have come out recently from studies on human inherited disorders of nociception. Point mutations in Na(v)1.7 have been identified in patients with two distinct autosomal dominant severe chronic pain syndromes. Electrophysiological experiments indicate that these pain-associated mutations cause small yet significant changes in the gating properties of voltage-gated sodium channels that are likely to contribute substantially to the development of chronic pain. Equally exciting, recent studies indicate that recessive mutations in Na(v)1.7 that eliminate functional current can result in an apparent complete, and possibly specific, indifference to pain in humans, suggesting that isoform specific blockers could be very effective in treating pain. In this review we will examine what is known about the roles of voltage-gated sodium channels in nociception.
Eugenics talk
Liberal Eugenics
'Designer babies'
Private eugenics
Psychiatric genetics
Human self-domestication
Selecting potential children
Preimplantation genetic diagnosis
'A life without pain? Hedonists take note'
Francis Galton and contemporary eugenics
Gene therapy and performance enhancement
The neurological basis of the emotional dimension of pain


reproductive-revolution.com
Refs

and further reading

HOME
Resources
Wireheading
BLTC Research
nootropic.com
Superhappiness?
Utopian Surgery?
The Good Drug Guide
The Abolitionist Project
The Hedonistic Imperative
The Reproductive Revolution
MDMA: Utopian Pharmacology
Critique of Huxley's Brave New World