Posted by Tomatheus on August 15, 2010, at 16:12:00
In reply to Re: RIMAs vs MAOIs » SLS, posted by ed_uk2010 on August 15, 2010, at 14:30:58
> Why would a selective & irreversible MAO-A inhibitor be more effective than Nardil/Parnate? I expect that such a drug would be somewhat better tolerated, but probably not more effective.
Am I allowed to respond? I don't want to get in the way of your dialogue with Scott, but I think it's only fair that I get to share my thoughts too.
Anyway, I suspect that a selective irreversible MAO-A inhibitor would be more effective than the nonselective irreversible MAOIs currently on the market because elevated levels of MAO-A have been implicated in major depressive disorder, but elevated levels of MAO-B have not. When treating any illness, the goal (in my opinion) should be to target the underlying pathology without creating any unnecessary chemical imbalances. Individuals with high MAO-A levels don't need their MAO-B levels messed with. They simply need their MAO-A levels to be reduced to a healthy, normal level. If MAO-B levels are already at a healthy, normal level, then taking a nonselective MAOI will cause MAO-B levels to drop to a level that's unhealthy. Low platelet MAO (MAO-B) levels have been associated with a subtype of schizophrenia characterized by auditory hallucinations (Schildkraut et al., 1976; Becker & Shaskan, 1977; Orsulak et al., 1978) and even with dysfunctional impulsivity and antisocial behavior (Eensoo et al., 2004). Of course, low MAO-A levels have also been associated with antisocial behavior and aggression, so lowering MAO-A levels too far can also be problematic. My point, though, is that for individuals with high MAO-A levels, it would be far more desirable to simply bring MAO-A levels down to a healthy, normal level without doing anything else than it would be to inhibit MAO-A and to bring MAO-B levels unnecessarily low.
I should point out that what I'm doing is making an educated guess as to whether or not a selective irreversible MAOI would be more effective than the nonselective irreversible MAOIs. There are no studies that I'm aware of that directly compare selective irreversible MAOIs with nonselective irreversible MAOIs, and until there are (which won't be any time soon), all we can really do is make educated guesses.
Tomatheus
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REFERENCES
Becker, R.E., & Shaskan, E.G. (1977). Platelet monoamine oxidase activity in schizophrenic patients. American Journal of Psychiatry, 134, 512-517. Abstract: http://ajp.psychiatryonline.org/cgi/content/abstract/134/5/512
Eensoo, D., Paaver, M., Pulver, A., Harro, M., & Harro, J. (2004). Low platelet MAO activity associated with high dysfunctional impulsivity and antisocial behavior: Evidence from drunk drivers. Psychopharmacology, 172, 356-358.
Orsulak, P.J., Schildkraut, J.J., Schatzberg, A.F., & Herzog, J.M. (1978). Differences in platelet monoamine oxidase activity in subgroups of schizophrenic and depressive disorders. Biological Psychiatry, 13, 637-647. Abstract: http://psycnet.apa.org/psycinfo/1980-09825-001
Schildkraut, J.J., Herzog, J.M., Orsulak, P.J., Edelman, S.E., Shein, H.M., & Frazier, S.H. (1976). Reduced platelet monoamine oxidase activity in a subgroup of schizophrenic patients. American Journal of Psychiatry, 133, 438-440. Abstract: http://ajp.psychiatryonline.org/cgi/content/abstract/133/4/438
poster:Tomatheus
thread:958646
URL: http://www.dr-bob.org/babble/20100811/msgs/958709.html