Dextroamphetamine questions

[AlphaMethylPhenyl]

I bet many of these have been covered. Sorry.


So if d-amp is more structurally related to serotonin by dopamine why is its effect on dopamine levels five times (guesstimate, corrections appreciated) greater?

I read a reviews of the pharmacology of amphetamine and it seems to be classified as a, let's see if I can remember, competitive monoamine substrate reuptake inhibitor?

So it binds to the dopamine transporter given structural similarity to dopamine, gets taken into cytistolic stores, then vmt2 transports it to vesicular stores where it pushes out dopamine into the synapse. It also acts as an agonist at dopamine and norepinepherine and the trace amine receptors (para-tyramine, beta-phenylethylamine, octopamine, etc) and at serotonin in higher doses, though causes release of serotonin through a dopinminergic mechanism. It also inhibits re-uptake and is a weak maoi. Am I right?

Does amphetamine exhibit greater ability to increase cognition in healthy individuals than caffeine? Methylphenidate?

I've heard that amphetamine is less of a crude stimulant relative to caffeine because it targets fewer brain regions, resulting in a more concerted focus, whereas caffeine produces a more peripheral and generalized stimulation.

It has so many mechanisms

By which mechanism does it increase preproenkephalin and other opiate peptides?

Thanks.

 

[sekio]

So if d-amp is more structurally related to serotonin by dopamine

what?

These sound like questions that could be answered by PubMed

 

[AlphaMethylPhenyl]

Than dopamine, I meant. I searched and couldn't find the answers to basically all. I thought based on knowledge of chemistry/bio people could give educated guesses too.

 

[sekio]

Structurally ampehtamine better overlays with dopamine/NE than it does with 5ht.

 

[AlphaMethylPhenyl]

Was my explanation of its mechanism right? Any other comments on my questions/statements? Thanks sek.

 

[Dresden]

Does amphetamine exhibit greater ability to increase cognition in healthy individuals than caffeine? Methylphenidate?

Yes, amphetamine (at a high enough dosage) exhibits greater ability to increase cognition in healthy individuals than caffeine or methylphenidate. 500mg of caffeine is bioequivalent to 20mg of amphetamine.

 

[Epsilon Alpha]

Yes, amphetamine (at a high enough dosage) exhibits greater ability to increase cognition in healthy individuals than caffeine or methylphenidate. 500mg of caffeine is bioequivalent to 20mg of amphetamine.

Source on the bio-equivalence info? I've seen indirect comparisons only

 

[TCMVegas]

Could be wrong, sorry for no source cited, but I believe that came from an army study on wakefulness under sleep deprivation

 

[AlphaMethylPhenyl]

By blocking reuptake its less effective at being taken up into the presynaptic cell. The two actions seem to somewhat cancel each other out...

 

[endotropic]

So if d-amp is more structurally related to serotonin by dopamine why is its effect on dopamine levels five times (guesstimate, corrections appreciated) greater?

Are you confusing d-amp with MDMA here? MDMA is closer structurally to dopamine, which always felt a bit backwards.

It also inhibits re-uptake and is a weak maoi. Am I right?

It inhibits re-uptake in that it causes the transporter to work in reverse. If it's pumping out it can't pump in.

It is an maoi in as much as any mao substrate is an maoi. I've never seen indication that d-amp inhibits mao any further than that.

 

[MrSpeedyG]

amp isnt a direct maoi... i guess if a few hundred mg were occupying mao enzyme then yeah but it isnt

 

[Hammilton]

All substrates technically inhibit MAO. Not meaningfully, though.