Can Designer Drugs Target Specific Brain Chemicals for Depression Management?

[Scratch]

For all of you who get depressed on a predictable time table, spring happy mid summer sad, fall happy, winter sad, type deal. Would it be possible for drug companies to make designer drugs paticular to what your various chemicals are at like dopamine. I mean is there a way to take out brain fluid to measure the levels (on a dya that your feeling good) of the three main chemicals that inffluence mood? Or would this be way to expensive for the average drug company to produce or are they happy to be producing drugs that pysch's hand out like candy?


Thanks

 

[Moonbear]

First, the neurotransmitters implicated in depression need to be measured locally by microdialysis in the specific areas of the brain where the problem is occurring. Brain surgery seems a little extreme to get a diagnosis of depression. It's also not quite so simple as "three main chemicals that influence mood."

Research into the causes and mechanisms of depression is still ongoing. The drugs we use now are used simply because they work, not because we fully understand what the cause of the problem is in the first place. Based on what drugs are helping improve depression, we have learned something more about some of the brain pathways involved, but have a long way to go.

There's even less information on seasonal depression than on more typical forms of depression.

 

[rygar]

you can figure out the amount of neurotransmitter in your brain from it's metabolites excreted through urine, such as homovanillic acid (HVA) for dopamine

but to my knowledge they don't really markers and metabolites when prescribing anti-depressants.

as for using a readout to adjust the level of a given drug... it's more of a trial and error thing. they'll start with a low dose and see how it works. usually a disorder will have consistent levels of a neurotransmitter, so an effective dose on one person would be effective on another, compensating for weight, gender, etc.

i don't think it's really necessary to design drugs around these levels, but i wouldn't mind taking physical neurotransmitter levels into account for diagnosis in the future!

 

[Moonbear]

you can figure out the amount of neurotransmitter in your brain from it's metabolites excreted through urine, such as homovanillic acid (HVA) for dopamine

Again, this is an oversimplification of the problem. Measurement of metabolites only gives you a whole body measure, not a measure of what's going on in a specific brain area that's involved in depression. Dopamine circulates throughout the body to affect many organ systems. It's also not necessary that the problem be in the transmitter release, but could also (and very likely is) due to problems with specific receptor subtypes for those neurotransmitters.

I'll leave the dopamine, dopamine receptor and monoamine transporter tutorial to DocToxyn though, if he's around and inclined to participate, because I know that's one of his areas of expertise more so than my area of specialization.