Posted by Marty on July 6, 2008, at 22:16:54
In reply to Re: +++ MAO-A or B ? Gerovital (procaine) selectivity, posted by SLS on July 6, 2008, at 13:56:46
Hi Scott,
> Just a quickie:
>
> http://biopsychiatry.com/clorgvparg.htm
>
> I bet the results of the study you cited were >in error. Clorgyline does not inhibit MAO-B at >any dosage. Again, this is a significant finding >when it comes to assessing therapeutic effect.I wonder what we are arguing about at this stage... as I'm sure we all agree that MAO-A inhibition helps more people than MAO-B inhibition BUT sometimes MAO-B inhibition works for some for which MAO-A inhibition didn't help much or enough.
Your quickie isn't helping your point much since it validate to some extent what Undopaminergic is telling you: quote "clorgyline, a preferential inhibitor of monoamine oxidase (MAO) type A"
PREFERENTIAL .. which means that it ALSO like EVERY OTHER MAOIs inhibit, to some level the untargeted isoform, MAO-B when dosage is sufficient. I wouldn't be surprised if there's no inhibitor -100%- specific to one isoform or the other. To my knowledge we don't have many very highly specific/selective molecule at this time. Even the most selective SSRIs somehow flirt with other things at some dosage. And how are we suppose to be PERFECTLY specific to one MAO isoform when they seems to share (yes I know, to some -very- small degree except dopamine and cie which they both equally *likes* ) all of the same substrates... ie: MAO-B does have some very small affinity for Serotonin even if MAO-A prefers it greatly. ... at higher dosage it seems impossible to NOT effect both isoform to some level.. specially in the case of a specific MAO-A inhibitor since MAO-B is only 30% of brains MAOs.
That said I feel WAY out of my league as to how scientist can be 100% specific to one isoform.. there is surely more differences betweens the two that there preferencial specificity for some substrates and maybe those other difference are "targetable" ... what do I know :)Anyway, why would we want a perfectly specific MAO-A or MAO-B inhibitor ? I'm sure we can live with an inhibition level of MAO-A 90%+ and MAO-B 30%- ... and MAO-A 10%- and MAO-B 90%+ .. I dont see the need to be more selective than that. Am I missing something ?
Hope your doing well,
/\/\arty
poster:Marty
thread:836966
URL: http://www.dr-bob.org/babble/20080706/msgs/838528.html