a dor e a pimenta / the pain and chili peppers.(also in english)

do site: boingboing.net Os seres humanos   evitam a pimenta. A fruta contém uma substância irritante  chamada capsaicina. É tão forte que um miligrama do material branco cristalino sem sabor, se colocado na palma da mão queima como um cigarro aceso e a dor dura horas. Nos mamíferos  as suas sementes morrem nas vísceras ao serem consumidas.. A capsaicina é a forma da planta de dizer " afaste-se" (Sementes de pimenta Chili pode sobreviver sendo comido pelas aves, que não têm receptores para sentir capsaicina. Na verdade, as plantas de pimenta "querem" aves para comê-los porque as aves são excelentes vetores de propagação da semente.) Diferentemente da maioria dos mamíferos, seres humanos desfrutam a queima de capsaicina em seu alimento e em grandes doses, a capsaicina faz com que a longo prazo ocorra a dessensibilização de neurônios que enviam sinais de dor ao cérebro. O laboratório  NeurogesX em San Carlos, Califórnia criou um adesivo transdérmico de alívio da dor que contém capsaicina. Foi revestida com um gel transparente adesivado.  NeurogesX foi fundada pelo Dr. Wendye Robbins, baseado em seu sucesso em 1997 com capsaicina no tratamento de pacientes com dor do nervo debilitantes. Robbins usou um creme contendo capsaicina quase 10%  em pacientes com HIV que tinham dor crônica e grave do pé e que  tinham sido incapaz de encontrar alívio usando qualquer outro medicamento, incluindo a morfina . Sessenta por cento dos pacientes de Robbin relataram  que a dor havia sido reduzida em pelo menos 50 por cento. Agora, com US $ 30 milhões em capital de risco, NeurogesX tem um sistema transdérmico no mercado chamado Qutenza, que contém capsaicina 8%. Uma única aplicação de uma hora pode aliviar a dor debilitante que muitas vezes resulta de um caso de herpes zoster.  Human beings are supposed to avoid chili peppers. The fruit contains a fiery irritant, called capsaicin. It’s so strong that one milligram of the flavorless white crystalline stuff placed in your palm burns like a lighted cigarette, and the pain lasts for hours. Chili peppers evolved this defense mechanism because their seeds die in the guts of mammals. Capsaicin is the plant’s way of saying “back off.” (Chili pepper seeds can survive being eaten by birds, which don’t have receptors to feel capsaicin. In fact, chili plants “want” birds to eat them because birds are excellent chili propagation vectors.) Unlike most mammals, human beings enjoy the burn of capsaicin in their food. And there’s another reason to like it besides its culinary thrill: in large doses, capsaicin causes long-term desensitization of neurons that send pain signals to the brain. That point was made clear to me a few years ago when I paid a visit to Neurogesx in San Carlos, California. Annika Malmberg, the director of pharmacological research showed me a transdermal pain relief patch containing capsaicin. It was coated with a clear gummy gel. When I reached out for it, she said, “Oh no! Don’t touch,” pulling it away and sticking it on the back of her own hand. “But you’re touching it,” I said. “Ahh,” she said, dismissively waving her other hand. “I’m completely desensitized.” If I had put the patch on, however, my hand would start to hurt like hell, at least until my nerve cells shriveled up. Neurogesx was founded by Dr. Wendye Robbins, based on her success in 1997 using capsaicin to treat patients with debilitating nerve pain when she was an assistant clinical professor of anesthesiology at the Mount Zion Pain Center in San Francisco. There, Robbins used a cream containing nearly 10% capsaicin (about 100 times the amount found in over-the-counter arthritic rubs) on HIV patients who had severe chronic foot pain and had been unable to find relief using any other drug, including morphine. Sixty percent of Robbin’s capsaicin patients reported that their pain had been reduced by at least 50 percent, and all the patients reported at least some pain relief. Now with $30 million in venture capital, Neurogesx has a transdermal patch on the market called Qutenza, which contains 8% capsaicin. A single, one-hour application can alleviate the debilitating pain that often follows a case of shingles. Neurogesx is currently running clinical trials to study other uses for capsaicin. Who would have thought that this natural compound, evolved to keep people away from it, would be so alluring?