Subject: Does St. John's Wort affect the serotoginic system of the brain? How?

I am interested in these questions especially regarding migraine 
headaches and serotonin levels.  

Hypericum Perforatum's is compared to Prozac, which interacts with 
the brain's serotonin levels.(Prozac is sometimes used for migraine 
profolaxis.)  Does St. John's Wort have any effect on the production, 
use, etc. of serotonin within the brain?  As well, does St. John's 
Wort have any affect on mono amine oxidase levels? How do MAO levels 
and serotonin affect each other?  

Re: Does St. John's Wort affect the serotoginic system of the brain? How?