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Vicc · 04-18-2007, 10:14 AM

Dear IHH, and, of course, everyone else,

First, Wikipedia can be a good resource, but anyone can post anything there. Misinformation abounds on that site. There is so much information about every aspect of medicine available on the Internet (stuff that has a solid source attribution), that this one really is far short of the best option.

IHH, you didn't get the chance to read a thread titled Why RSD Pain is Different that I posted at BrainTalk (and one which I still hope someone saved, because I didn't and can really use it now), in which I described a simple experiment in which allodynia can be induced in less than 30 minutes in anyone.

All one needs to do, and no one with RSD should ever try it, is apply a blood pressure (BP) cuff to your arm, raise the pressure to above systolic and let it remain for 30 minutes (probably less). At the end of this period, the arm and hand will be the familiar color of cyanosis and the touch of an ice cube to the tip of the thumb will produce the magnificant burning pain of allodynia. People with RSD should not try this, as it's probably the best way to induce symptom migration.

(Having your BP taken is not the same. The cuff is only inflated for a very short time so the risk is minimal at worst).

We don't need speculation that nerve damage may lead to decreased firing thresholds of nociceptors. The fact that we don't is helpful because nociceptors are not nerves; they are the nerve endings of C-fiber neurons. Nerves are the bundles of the fibers at the other end of neurons. They are buried well below the skin surface, where they are protected against damage, and carry various messages (including pain) to and from the brain and the body.

I am not correcting you; I am pointing out that there are real and very precise words for the parts of our bodies and it really is inexcusable for any doctor to talk about nociceptors as nerves: it results in obfuscation and confusion.

We don't need postulates about peripheral nerve injury inducing sprouting ot A-beta neurons in the dorsal horn, because it has already been proved that A-beta neurons stimulate the release of GABA in the dorsal horn.

A-beta neurons contain the nerve endings that tell the brain about the environment: touch, weight (to a degree), texture, even the sense of a light breeze. They are larger and faster than C-nociceptive neurons and are insulated. This means they have greater energy needs than the latter and respond more quickly to hypoxia (the result of the BP cuff left on).

GABA are inhibitory neurotransmitters. Basically, this means that they take up parking places on the receptors of the receiving neurons at synapses, preventing active neurotransmitters from finding a parking place and passing their chemical messages on to the receiving nerve.

It is no coincidence that GABAergic drugs, like Neurontin (gabapentin), and Lyrica are used to reduce RSD and other neuropathic pain: By stimulating GABA in the dorsal horn, A-beta fibers actually modulate the pain signals of C-nociceptive neruons; they do it, as I said, by stimulating natural GABA. When A fibers are denied adequate oxygen and nutrients they don't function properly and don't stimulate GABA, so we take GABAergic drugs.

I said it in my reply to Bronco's thread Upset: we know our skin is cyanotic, and I showed that the only neurological explanation for cyanosis isn't present in RSD, so we have to face the facts: the experts are lying to us.

Everyone here is free to believe what you want about RSD, but if you are willing to take the time and make the effort to learn everything you can about this disease, you won't be able to believe the experts any longer. Since this disease has taken almost everything from us, I think learning all you can is worth the effort.

I know that some people don't think they're smart enough to learn all that medical stuff, so I chose to devote what's left of my life teaching people what I've learned by using words we can all understand. There are medical words that can't be replaced by "people talk" but I define those words in ways we can all understand.

Meanwhile, I remain grateful to Kris Kristofferson, a truly great songwriter even if he had never writter To Beat the Devil; but he did. If you want to know what that means, you'll have to listen to the song...Vic