Re: Neues aus der Opiumforschung

verfasst von Bob, 11.11.2003, 16:36

-->Kurze Einführung: Zu jeder Droge gibt es einen sog. Antagonisten, d.h. eine Substanz, die geeignet ist, die Wirkung der Droge aufzuheben. Die Idee hier besteht darin, einem schmerzstillenden Opiat eine sehr geringe Menge (ultra-low-dose) eines Opium-Antagonisten beizumischen. Das Resultat ist kaum erklärbar aber wohl deutlich genug, um dahingehend zu forschen.

...

On November 8th, Francesco Leri, Ph.D., Assistant Professor at University of Guelph, Canada, presented the results of a pre-clinical model of addiction and relapse. In this model, rats are trained to self-administer opiates alone or in combination with ultra-low-dose opioid antagonists. Dr. Leri found that rats that previously self-administered opiates plus ultra-low-dose opioid antagonists showed significantly reduced"drug-seeking" behavior compared to rats that self-administered the same amount of the opiate drug. These pre-clinical data suggest that ultra-low-dose opioid antagonists may attenuate addictive drug-seeking commonly observed after chronic opiate use.

On November 9th, Mary C. Olmstead, Ph.D., Assistant Professor at Queen's University, Canada, presented the results of a pre-clinical model of opioid withdrawal. In this experiment, rats chronically treated with opiates avoided a compartment in a testing box where they previously experienced opiate withdrawal. In contrast, rats chronically treated with opiates combined with ultra-low-dose antagonists showed no aversion to this area, indicating no withdrawal was experienced. These pre-clinical data suggest that ultra-low-dose opioid antagonists can prevent the aversive withdrawal that is commonly observed after chronic opiate use.

The third poster presentation examines what happens to brain cells in opioid tolerant rats.

"It's well known that nerve cells become tolerant when exposed to chronic doses of opioids," said Eitan Friedman, Ph.D., Professor and Chair, Department of Pharmacology and Physiology, CUNY Medical School."From a clinical perspective, tolerance means a patient takes more drug over time just to maintain a constant level of pain relief, even in the absence of disease progression. How this happens on a cellular level is the subject of much research. We have now confirmed a dramatic change in the opioid receptor that we think is very important."


Today, Dr. Hoau-Yan Wang, Associate Medical Professor at CUNY Medical School, will show that opioid receptors switch into an abnormal signaling mode during tolerance or dependence. Opioid receptors normally send inhibitory signals into the cell. During tolerance or dependence, inhibitory signals are replaced by excitatory signals, according to Dr. Wang's data. These excitatory signals use a novel protein not normally used by opioid receptors. Dr. Wang also shows that excitatory signals can be blocked by ultra-low-dose naloxone, effectively blocking tolerance or dependence. These results suggest a molecular explanation for the ability of ultra-low-dose opioid antagonists to attenuate tolerance and dependence.

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gesamter Thread:

• Gulbuddin Hekmatjar droht auch deutschen Soldaten - stocksorcerer, 11.11.2003, 16:04
  • LOL, hier das Bild ;-) - stocksorcerer, 11.11.2003, 16:05
    • Re: Neues aus der Opiumforschung - Bob, 11.11.2003, 16:36