MAOIs: Multiple Effects and Sites of Action

Re^3: Symposium 524

Thank you very much for all of your interest in my poster. It is really nice to get feedback!

As mentioned in my poster, clorgyline has an affinity for many sites; the enzyme MAO, sigma binding sites, the I2 imidazoline receptor site, and the MQB site. My clorgyline/moclobemide study determined that clorgyline's action at the MAO-A enzyme does not result in the blockade of quinpirole induced locomotor sensitization, and suggested that the MQB site may be involved.

Unfortunately, moclobemide has little affinity for sigma and I2 sites, and an interaction at these sites must be discounted before I can begin to attribute my results to clorgyline's activity at MQB. Furthermore, moclobemide has no affinity for MAO-B and since (as you've stated) there is an association between I2 sites and MAO-B this possibility should also be examined.

If chronic 2-BFI treatment is found to block quinpirole-induced locomtor activity, then that would be an indication that the I2 site is involved in locomotor sensitization to quinpirole. Alternatively, if 2-BFI has no effect, it leads us one step closer to implicating the MQB site in sensitization.

I am not very familiar with amiloride... I have read briefly about its affinity for the MAO-A I2 binding site, and am interested in its action. Could you tell me more?

If you have any other sugesstions I would love to hear them.Thanks again for all of your comments, Kirsten.

Tue Dec 15