|MadSci Network: General Biology|
You have asked a very interesting question, one that is actually related to current biomedical research. We are learning a whole lot about what kind of substances are found in the signalling pathways of "love." Since I'm not sure just how much detail you need, I will give you an overview of the substances, and some links to follow. If you need to know the body systems that effected by the substances, you can either write back, or take a look through one of the neuroscience websites.
Basically, what we know about the feelings that are associated with "love" is that they are related to certain chemicals that are released in the body of those "in love." One of those substances is b-phenylethylamine (PEA) norepinephrine. This substance triggers the breakdown of glycogen and triacylglycerols, which provides the body a boost of energy. That's the "high" of being "in love."
For more information, I would suggest:
Good luck. Hope this helps!
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