Contribution of tetrahydropapaveroline & tetrahydroisoquinoline derivatives...

[Riemann Zeta]

There has been quite a bit of investigation into the interaction of ethanol with opioid receptors. Much of this was spurred by the finding that naltrexone and other mu antagonists help reduce EtOH consumption in chronic alcoholics. Other research has demonstrated the in vivo formation of tetrahydropapaveroline and other tetrahydroisoquinonline derivatives from ethanol, dopamine and MAO. Many suggest tetrahydropapaveroline is an opioid, but I have never seen anyone do a simple competitive binding assay to test its Ki for the mu-receptor. Others suggest that tetrahydropapaveroline is only an intermediate, leading to the complete in vivo synthesis of morphine-like opioids. This seems a little unlikely that we posses an entire set of enzymes for the synthesis of morphine or morphine-esque compounds. Even more interesting is the observation that mice that have consumed EtOH chronically for 18 mos. endogenously synthesize (S)-tetrahydropapaveroline, but those that have consumed it for 6 mos. do not. Does alcoholism turn on genes for morphine synthesis?

Then there is a the phenomenological argument--does EtOH feel like an opioid at all? I have never experienced an opioid (aside from dextropropoxyphene, which, judging from this board, should not count as a real opioid), but I have obviously experienced EtOH. I will admit, it does produce some analgesia, but I always attributed this to its NMDA-R and (putative) nAChR antagonism.

Anyone else interested in the mechanism of action of EtOH?

 

[Gaz_hmmmm]

Then there is a the phenomenological argument--does EtOH feel like an opioid at all?

I know that when I'm tried or have gone a few hours without food then drink say a few doubles, 3, maybe 4, it sometimes feels abit like an opiate, especially when I'm just chilling and slouching or laying down!

 

[Morninggloryseed]

Re: Human Cells Producing Morphine

This seems a little unlikely that we posses an entire set of enzymes for the synthesis of morphine or morphine-esque compounds.

This article contends that it is possible.

By Kristen Philipkoski in Wired

Meinhart Zenk and his colleagues at Martin-Luther-University Halle-Wittenberg in Germany found that human cells grown in a dish synthesized morphine.

"Without doubt, human cells can produce the alkaloid morphine," Zenk wrote in the paper. "The studies presented here serve as a platform for the exploration of the function of 'endogenous morphine' in the neurosciences and immunosciences."

Don't know the reliability of the article, but I have no reason to doubt it. Interesting theory either way.

 

[who mE?]

teehee, I did a search on google for:
human morphine bioproduction
and the first 2 results were on my site:
http://hive.dopers.org/pdfs/morphine bioproduction.htm
http://hive.dopers.org/pdfs/morphine more bioproduction.htm

haha, this is a proud day for me... I beat out the royal society of chemistry... (damn I should probably update my site, its been over a month, and I've got 400 links and a couple articles waiting for a home)