Tag Archives: neuroscience

Physiologic Effects of Pain on the Endocrine System

The Physiologic Effects of Pain on the Endocrine System – Free full-text PMC4107914 – Pain Ther. 2013 Dec – by Forest Tennant

Severe pain has profound physiologic effects on the endocrine system.

Serum hormone abnormalities may result and these serve as biomarkers for the presence of severe pain and the need to replace hormones to achieve pain control.

Initially severe pain causes a hyperarousal of the hypothalamic–pituitary–adrenal system which results in elevated serum hormone levels such as adrenocorticotropin, cortisol, and pregnenolone.

If the severe pain does not abate, however, the system cannot maintain its normal hormone production and serum levels of some hormones may drop below normal range.   Continue reading


Testosterone to treat central sensitization

A novel use for testosterone to treat central sensitization of chronic pain in fibromyalgia patients – ScienceDirect – August 2015


  • Testosterone is effective therapy for fibromyalgia.
  • Low/deficient testosterone levels are linked to a high risk for chronic pain states.
  • Novel mechanisms by which testosterone is likely to down-modulate pain signals
  • Mechanisms involving testosterone are linked to central sensitization.

Continue reading

Filling-In, Spatial Summation, and Radiation of Pain

Filling-In, Spatial Summation, and Radiation of Pain: Evidence for a Neural Population Code in the Nociceptive System – Free full-text PMC2804406 – J Neurophysiol. 2009 Dec

The receptive field organization of nociceptive neurons suggests that noxious information may be encoded by population-based mechanisms.

Electrophysiological evidence of population coding mechanisms has remained limited.

However, psychophysical studies examining interactions between multiple noxious stimuli can provide indirect evidence that neuron population recruitment can contribute to both spatial and intensity-related percepts of pain. Continue reading

Do Nav1.7 inhibitors work for neuropathic pain?

What are Nav1.7 inhibitors and how are they used in the treatment of neuropathic pain? – August 2017 – By McKenzie C. Ferguson, PharmD, BCPS

Nav1.7 is a voltage-gated sodium channel isoform encoded by the SCN9A gene.

The Nav1.7 channel is normally expressed in the dorsal root ganglion neurons, trigeminal neurons, and their small-diameter peripheral axons

Mutations in these isoforms have been associated with several pain disorders, including erythromelalgia, paroxysmal extreme pain disorder (PEPD), congenital insensitivity to pain (CIP), and painful peripheral neuropathy.   Continue reading

Chronic Pain Causes Brain Damage

Functional Reorganization of the Default Mode Network across Chronic Pain Conditions – PLoS One. – Sep 2014

Here we use resting-state functional magnetic resonance imaging to investigate functional changes in patients suffering from chronic back pain (CBP), complex regional pain syndrome (CRPS) and knee osteoarthritis (OA).

We isolated five meaningful resting-state networks across the groups, of which only the default mode network (DMN) exhibited deviations from healthy controls.

All patient groups showed

  1. decreased connectivity of medial prefrontal cortex (MPFC) to the posterior constituents of the DMN, and
  2. increased connectivity to the insular cortex in proportion to the intensity of pain.  Continue reading

Pain Tolerance and C-reactive protein

C-reactive protein and cold-pressor tolerance in the general population : PAIN – July 2017

Pain and inflammation are related: systemic inflammation may lead to a variety of pain states, and, in turn, persistent pain causes an upward adjustment of proinflammatory mediators that sometimes elicit a prolonged low-grade immune response, leading to long-lasting, subclinical inflammation.

The cytokines that are produced during inflammatory responses are the main stimulators of the production of acute-phase proteins, specifically C-reactive protein (CRP).

C-reactive protein is a nonspecific systemic marker of infection, inflammation, tissue damage, malignancy, and autoimmune disease.  

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Study sheds new light on how body processes pain

How does the body process pain? Study sheds new light – Medical News Today  by Ana Sandoiu – June 2017

Currently available pain medications have limited efficacy and numerous side effects. New research, however, provides deeper insights into how our bodies process pain, paving the way for an innovative, more effective way of targeting chronic pain.

According to recent estimates from the National Institutes of Health (NIH), as many as 25 million people in the United States live with daily pain, and 23 million of the country’s adults have more severe pain.

Previous efforts to develop more effective analgesics have been stalled by our limited understanding of the mechanisms that allow nerves to sense and transmit pain signals,” Dr. Bunnett says.   Continue reading

New opioid active only where inflammation present

A New Opioid Targets Active Sites of Inflammation to Relieve Pain – by Nathan T. Fried on 23 Mar 2017

Summary: NFEPP binds and activates mu-opioid receptors only at low pH, soothing pain in rats without typical side effects

Adverse effects of opioids can occur because the drugs act at both injured and healthy tissue, but if researchers could find a way to direct opioids only to the former and not the latter, perhaps the drugs would lack off-target activity.

Now, a new report reveals the design of a novel opioid that only works where inflammation exists, leaving healthy tissue untouched and avoiding the unwanted consequences seen with traditional drugs.   Continue reading

How Slow Breathing Induces Tranquility

How Slow Breathing Induces Tranquility – Neuroscience News – Mar 2017

Stanford scientists have identified a small group of neurons that communicates goings-on in the brain’s respiratory control center to the structure responsible for generating arousal throughout the brain.

Try it. Breathe slowly and smoothly. A pervasive sense of calm descends. Now breathe rapidly and frenetically. Tension mounts. Why?

It’s a question that has never been answered by science, until now.

In a new study, researchers at the Stanford University School of Medicine and their colleagues have identified a handful of nerve cells in the brainstem that connect breathing to states of mind.   Continue reading

Glial Cells: “Missing Link” in the Physiology of Pain

The “Missing Link” in the Physiology of Pain: Glial Cells – Practical Pain Management – May 2016

glial cells and their interactions have become recognized as having a critically important role in the generation and maintenance of acute and chronic pain… and may now be a “missing link” in our understanding of the conversion of acute to chronic pain and the development of chronic neuropathic pain

This conversion process has been called “chronification,” and includes

  • central sensitization,
  • neuroplastic changes,
  • altered pain modulation, and
  • changes to the “neuromatrix” of the central nervous system.

Continue reading