Breaking News
February 20, 2019 - Study sheds new light on how antibiotic resistance genes are transferred between bacteria
February 20, 2019 - Chronic Wasting Disease may soon spread to humans, warns CDC
February 20, 2019 - Scientists identify new genetic causes linked to abnormal pregnancies and miscarriages
February 20, 2019 - Using LyoSpeed technology to avoid residual solvent when drying HPLC fractions
February 20, 2019 - New screening tool more likely to identify sexual and labor exploitation of youth
February 20, 2019 - Newly licensed nurses work for long hours, also have a second paid job
February 20, 2019 - Physicists identify simple mechanism used by deadly bacteria to fend off antibiotics
February 20, 2019 - FDA Grants Priority Review to Genentech’s Personalized Medicine Entrectinib
February 20, 2019 - Exposure to chemicals before and after birth is associated with a decrease in lung function
February 20, 2019 - Neuroscientists reveal that simple brain region can guide complex feats of mental activity
February 20, 2019 - Study finds new link between food allergies and multiple sclerosis
February 20, 2019 - First gene therapy operation for macular degeneration is a success
February 20, 2019 - Physicians graduated outside the U.S. offer better care for Medicare patients with complex needs
February 20, 2019 - FDA Approves Keytruda (pembrolizumab) for the Adjuvant Treatment of Patients with Melanoma with Involvement of Lymph Node(s) Following Complete Resection
February 20, 2019 - Study identifies brain cells that modulate behavioral response to threats
February 20, 2019 - Researchers take closer look at how viruses bind cells and cause infection
February 20, 2019 - Newly developed gene therapy helps decelerate aging process
February 20, 2019 - Study suggests new treatment strategy for deadly brain cancer
February 20, 2019 - Scientists develop unique hybrid implant that imitates bone structure
February 20, 2019 - Push-ups can be tailored to meet specific needs of individuals
February 20, 2019 - Early-career job loss has long term health implications
February 20, 2019 - CVD Does Not Modify Depression-Mortality Link in Elderly
February 20, 2019 - Electrical activity early in fruit flies’ brain development could shed light on how neurons wire the brain
February 20, 2019 - Machine learning technique helps predict which asthma patients respond to corticosteroid therapy
February 20, 2019 - Self-reported sleep duration is a useful tool to measure sleep in children, study suggests
February 20, 2019 - T-cells play key role in how the body fights follicular lymphoma
February 20, 2019 - Study shows how 3D organization of genetic material helps perpetuate the species
February 20, 2019 - Researchers engineer stem cell with ‘suicide genes’ to induce cell death in all but beta cells
February 20, 2019 - Study reveals major sex differences in management of cardiovascular risk factors among U.S. adults
February 20, 2019 - Health Tip: Get Your Child to School on Time
February 20, 2019 - Shortcut strategy for screening compounds with clinical potentials for drug development
February 20, 2019 - Common acid reflux drugs tied to elevated risk for kidney disease
February 20, 2019 - Microbiome could be culprit when good drugs do harm
February 20, 2019 - Prenatal exposure to forest fires causes stunted growth in children
February 20, 2019 - Gene therapy restores hearing in mice with congenital genetic deafness
February 20, 2019 - First molecular test predicts treatment response for kidney cancer
February 20, 2019 - New method for improved visualization of single-cell RNA- sequencing data
February 20, 2019 - Researchers capture altered brain activity patterns of Parkinson’s in mice
February 20, 2019 - A possible blood test for detecting Alzheimer’s disease before symptoms show
February 20, 2019 - Primary care physicians associated with longevity, new research finds
February 19, 2019 - New study identifies many key lessons to establish sanctioned safe consumption sites
February 19, 2019 - Single CRISPR treatment can safely and stably correct genetic disease
February 19, 2019 - Multinational initiative to study familial primary distal renal tubular acidosis
February 19, 2019 - Breakthrough study highlights the promise of cell therapies for muscular dystrophy
February 19, 2019 - Subsymptom Threshold Exercise Speeds Concussion Recovery
February 19, 2019 - Midline venous catheters – infants: MedlinePlus Medical Encyclopedia
February 19, 2019 - Searching for side effects
February 19, 2019 - Humanity is all right, probably, although human extinction remains quite possible, researcher says
February 19, 2019 - Having Anesthesia Once as a Baby Does Not Cause Learning Disabilities, New Research Shows
February 19, 2019 - Anti-cancer immunotherapy could be used to fight HIV
February 19, 2019 - Customized Micropatterning for Improved Physiological Relevance
February 19, 2019 - Unique gene therapy approach paves new way to tackle rare, inherited diseases
February 19, 2019 - Activating gene that helps excite neurons reverses depression in male mice
February 19, 2019 - Science Puzzling Out Differences in Gut Bacteria Around the World
February 19, 2019 - Cells that destroy the intestine
February 19, 2019 - On recovery, vulnerability and ritual: An exhibit in white
February 19, 2019 - Scientific Duo Gets Back To Basics To Make Childbirth Safer
February 19, 2019 - COPD patients need more support when understanding new chest symptoms
February 19, 2019 - Using light-based method for production of pharmaceutical molecules
February 19, 2019 - Scientists find link between inflammation and cancer
February 19, 2019 - The High Cost Of Sex: Insurers Often Don’t Pay For Drugs To Treat Problems
February 19, 2019 - Hearing impairment associated with accelerated cognitive decline with age
February 19, 2019 - Researchers identify multiple genetic variants associated with body fat distribution
February 19, 2019 - Influenza and common cold are completely different diseases, study shows
February 19, 2019 - Scientists untangle how microbes manufacture key antibiotic compound
February 19, 2019 - Greater primary care physician supply associated with longer life spans
February 19, 2019 - HIV-1 protein suppresses immune response more broadly than thought
February 19, 2019 - Brain imaging indicates potential success of drug therapy in depressive patients
February 19, 2019 - For 2020 Dem Hopefuls, ‘Medicare-For-All’ Is A Defining Issue, However They Define It
February 19, 2019 - Specialized lung cells appear in the developing fetus much earlier than previously thought
February 19, 2019 - KU professor discusses promise of brain-computer interface to aid, restore communication
February 19, 2019 - Highly effective solution for detecting onset of aggregation in nanoparticles
February 19, 2019 - Early marker of cardiac damage triggered by cancer treatment identified
February 19, 2019 - Antidepressant drug could save people from deadly sepsis, research suggests
February 19, 2019 - CRISPR technology creates pluripotent stem cells that are ‘invisible’ to the immune system
February 19, 2019 - New study establishes how stress favors breast cancer growth and spread
February 19, 2019 - Midlife Systemic Inflammation Linked to Later Cognitive Decline
February 19, 2019 - Therapy derived from parasitic worms downregulates proinflammatory pathways
February 19, 2019 - Antimicrobial reusable coffee cups are less likely to become contaminated with bacteria, study shows
February 19, 2019 - Harnessing the evolutionary games played by cancer cells to advance therapies
Post-surgical opioids can prolong pain for more than three weeks, study shows

Post-surgical opioids can prolong pain for more than three weeks, study shows

image_pdfDownload PDFimage_print

Giving opioids to animals to quell pain after surgery prolongs pain for more than three weeks and primes specialized immune cells in the spinal cord to be more reactive to pain, according to a new study by the University of Colorado Boulder.

The authors say the paradoxical findings, if replicated in humans, could have far-reaching implications for patient pain management and add a new wrinkle to the conversation about the national opioid epidemic.

“This indicates that there is another dark side of opiates that many people don’t suspect,” said senior author Linda Watkins, a professor in the Department of Psychology and Neuroscience. “It shows that trauma, including surgery, in combination with opiates can lead to chronic pain.”

For the study, Watkins and co-author Peter Grace, then an assistant research professor at CU Boulder, performed exploratory abdominal surgery, or laparotomy, on male rats. A similar procedure is done tens of thousands of times annually in the United States in humans, and opiates are routinely used after surgery.

“Opiates are really effective for acute pain relief. There is no drug that works better. But very little research has been done to look at what it is doing in the weeks to months after it’s withdrawn,” said Grace, now an assistant professor at MD Anderson Cancer Center in Houston.

In one experiment, half the rats were given the equivalent of what would be a “moderate” dose of morphine in people for seven days postsurgery. Half were given a saline solution.

In another experiment, the rats were given morphine for eight days and then tapered off by day 10. In a third, the animals were given morphine until day 10 and then it was abruptly withdrawn.

Before and after the treatments, the researchers measured the animal’s sensitivity to touch as well as activity of genes that express inflammatory proteins in the spinal cord.

They found that rats given morphine experienced postoperative pain for more than three weeks longer. The longer they received morphine, the longer their pain lasted. And gradual tapering made no difference.

“This tells us that this is not a phenomenon related to opioid withdrawal, which we know can cause pain. Something else is going on here,” Grace said.

Watkins describes that something as a “one-two hit” on specialized immune system cells called glial cells in the central nervous system. The first hit, the surgery, stimulates what she calls the “not me, not right, not OK” receptor, Toll-like receptor 4 on the cells, igniting the release of a cascade of inflammatory proteins and “priming” them to be on guard for a second hit.

Morphine, which also stimulates that receptor, is the second hit.

“With that second hit, the primed glial cells respond faster, stronger and longer than before, creating a much more enduring state of inflammation and sometimes local tissue damage,” she said.

In a previous study, published in the Proceedings of the National Academy of Sciences in 2016, the researchers showed that just a few days of treatment with opiates to treat peripheral nerve pain, such as sciatica, could exacerbate and prolong pain for months in animals, in part by increasing expression of inflammatory genes.

A few small studies in humans have associated postsurgical opioid administration with chronic pain as much as one year later.

“An unusually high number of people end up with postoperative chronic pain. This new study lends insight into one explanation for that,” Watkins said.

The researchers, acknowledging that animal studies cannot directly translate to humans, are now calling for more clinical studies on opioids and chronic pain.

More than 50 million U.S. adults experience chronic pain, according to the National Institutes of Health.

Watkins is also studying novel compounds that could be given with opioids to mute the exaggerated immune response they are believed to trigger, as well as alternative painkillers, including cannabinoids, for pain.

“There is surely a dark side in terms of addiction when it comes to opioids, but this is a very different idea–that we think we are treating the pain with these drugs and we may actually be prolonging it,” she said.

Source:

https://www.colorado.edu/today/2018/04/16/opioids-after-surgery-can-paradoxically-prolong-pain

Tagged with:

About author

Related Articles