Serotonin

I'm trying to understand the role of serotonin more. I understand platelets carry serotonin. So if you have fewer platelets, does not as much serotonin get where it needs to go? Is this why some of us have more anxiety/depression issues? And also migraines, since serotonin can affect those as well?

I am on the fence about the ITP/Serotonin depression connection. I've never really found an article that supports it well. I have read that platelets carry only 2% of serotonin to the brain which does not seem like much. Some ITP patients are not depressed at all even with low counts and most depression seems to stem from steroids or fear/frustration with the disorder.

If you find anything, please post it.

Thank you Sandi. I've only read that on here about platelets carrying serotonin. But didn't know how much. My doctor had said that, too, but we didn't go into further discussion about it. I had anxiety issues before ITP, and I definitely have been worse than I am now. I am more curious about my migraines. I'm getting about 2-3 a month since my ITP diagnosis. I know stress and hormones are likely the biggest factors, but thought maybe this could be playing into it as well.

I can't remember if you've been tested for APS?

As far as migraine is concerned, it is an excess of serotonin causing vasoconstriction that is theorized as causing migraine headaches. The excess serotonin is released from the platelets because they are "sticky" and tend to aggregate, causing shear stress when they pass through narrow capillaries. Very counter-intuitive, but that is the theory, and it is an old theory that may not have gone anywhere. You can find more on it by googling migraine serotonin platelet.

Ellen has had some success using a tricyclic antidepressant called nortriptyline as a migraine preventative, and of course it works as an antidepressant as well.

Thank you, Rob! That is good info to know.

Yes, Sandi, I was tested in May. It was negative. But they'll test again when I'm done breastfeeding. That really freaks me out, though.

I remember now, sorry. Don't freak out.

Just a general observation here: Serotonin does not cross the blood-brain barrier (BBB). The neurons in the brain make their own serotonin using the pathway tryptophan -> 5-hydroxytrytophan -> serotonin. This is why we have to use TCAs and SSRIs etc. when treating depression and anxiety. They modulate the levels of serotonin by inhibiting MAO or affecting cellular pumps, or other mechanisms that are not currently well understood. Of course, blood vessels that pass through the brain are on the outside of the BBB, and their behavior can be affected by serotonin, as Rob pointed out in his comments on migraines.

Taz if you had anxiety before ITP and are now worse couldn't it be because you are worried/concerned/scared/etc more now than before ITP and this has nothing really to do physically with ITP? Just a thought. I think we tend to "think" too much and try to pin too much on ITP.