Posted by Astounder on October 31, 2007, at 17:56:02
In reply to Complicated biochem question - for you smarties, posted by Jimmyboy on October 29, 2007, at 13:52:57
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> About a month ago I took an intravenous dose of scopolamine hoping it would help my bipolar depression . ( Its in clinical trials for this) Well it did not help and it seems to have made some ( hopefully not permanent!!!) changes in my body.
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> Basically, I feel as if I have lost all creativity , feel real flat and have completely lost all sex drive ( which was strong before).
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> Now in the literature it says that scopolamine is a strong muscarinic antagonist, this has to do with the acetylcholine system.
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> Could getting a massive dose of an antagonist to this do something to the receptors for acetylcholine or what, I'm lost here . The study said that the effect of the drug could last from days to months... uh.. I hope it doesn't last many more months b/c this sucks.
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> By the way, it was definitely from this and this alone, it was very pronounced and immediate, so I know those symptoms have to do with this drug.
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> Any tips to even things out and get back to normal would be greatly appreciated.
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> JBI've taken deliriant doses of scopolamine and other anticholinergics before, and didn't suffer long-term ill effects. Acetylcholine receptors in general are quite resistant to plastic change. It's probably not something to do with the mAChRs themselves.
Rather the theory behind the acute scopolamine infusions is the same as the one behind acute ketamine infusions: An increase in brain-derived neurotrophic factor (BDNF). BDNF in the hippocampus is necessary for antidepressants to reverse learned helplessness. However, BDNF in other areas of the brain do not have positive effects: BDNF in the amygdala is anxiogenic and in the accumbens it's depressogenic in animals. It's probable that in some persons, lack of BDNF is preventing response to antidepressants, but that doesn't seem to be so in your case, and maybe BDNF simply rose in these "bad" areas.
If you really think you're not getting enough central mACh activity, you could ask your doc for a cholinersterase inhibitor like they use for Alzheimer's, however they have been reported to worsen depressive symptoms.
poster:Astounder
thread:792174
URL: http://www.dr-bob.org/babble/20071027/msgs/792603.html