Psychotropic drugs

[CraigD]

I’ve a couple of question about the physiological mechanism of psychotropic (mind altering) drugs in general.

As best I understand, psychotropics work in 4 broad ways

• Blocking nerve depolarization by binding to sodium channels
• Binding to a receptor, either to activate it, prevent its activation by its usual neurotransmitter, prevent the reuptake of a neurotransmitter, or otherwise alter the usual transmitter-receptor interaction.
• Chemically retard or increase the rate at which neurotransmitters break down into neurologically inert molecules
• Bind with and disable, or chemically degrade the usual molecules that retard or increase the rate at which neurotransmitters break down

My questions: am I missing a significant mechanism? Are other mechanisms, if not found in human of animal physiology, possible in principle?

[Racoon]

yeah,

Which chemicals and neurotransmitters ? ...

Plus absorbtion levels, (which might/could be included in your 4th bullet point)

[Michaelangelica]

Originally Posted by CraigD

[*]Binding to a receptor

This interests me
I have learnt on this forum that there are not only cannaboid receptors (I knew about opiate receptors) but also psychotropic receptors in the human brain.
These have been designed by us just as keys are made to fit locks

If a person hallucinates in psychotic disorders such as Schizophrenia (or in religious "ecstasy") does that mean he is producing his/her own internal psychotropic drugs?
just as the long-distance runner produces his own opiates?

If that is the case Schizophrenia may be helped by something that stops this process ????

[billg]

Originally Posted by Michaelangelica

This interests me
I have learnt on this forum that there are not only cannaboid receptors (I knew about opiate receptors) but also psychotropic receptors in the human brain.
These have been designed by us just as keys are made to fit locks

If a person hallucinates in psychotic disorders such as Schizophrenia (or in religious "ecstasy") does that mean he is producing his/her own internal psychotropic drugs?
just as the long-distance runner produces his own opiates?

Most psychotropic drugs act, as mentioned previously, by activating or inhibiting certain neurons by stimulating or blocking receptors on the neurons. So while it is probable that disorders like schizophrenia (and more controversially religious experiences) are a result of defects in the brain systems affected by drugs such as cocaine or LSD, it is not because they produce a chemical we don't, but rather because either they produce more or less of it, or because their receptors are more or less sensitive, or because they have more receptors.

Originally Posted by Michaelangelica

If that is the case Schizophrenia may be helped by something that stops this process ????

Yes, though I don't think it's that simple, especially not for schizophrenia. They do give drugs to schizophrenic patients, and the drugs that seem to work at alleviating symptoms are part of the reason they think certain types of receptors (such as dopamine and serotonin) are involved in such diseases - if they work, it makes sense the system they act on is involved. Unfortunately, schizophrenia is much more complex than that, and there may be many, many chemical differences between parts of a schizophrenics brain and ours, and the brain may even have altered anatomical structure as well, so its unlikely a single chemical will be found that's a "cure-all". More likely just ways to treat some symptoms.

[Michaelangelica]

Originally Posted by billg

Unfortunately, schizophrenia is much more complex than that, and there may be many, many chemical differences between parts of a schizophrenics brain and ours, and the brain may even have altered anatomical structure as well, so its unlikely a single chemical will be found that's a "cure-all". More likely just ways to treat some symptoms.

Yes, just a bit of wishful thinking.

Are the chemical receptors for psychotropic drugs simialr to opiate & MJ receptors?

It is strange that LSD trips and pellagra and schizophrenia have similar symptoms. Is there a common link?

[sun]

they've tested lsd on schizo's for a long time,
and lsd on balanced kids like us, too
and the acid barely affects the crazy,
Only in severe doses.
It is proven that schizo's are imbalanced
and some experience a good trip
and some experience a bad.

[Drip Curl Magic]

It's strange to think

that schitzophrenics are just tripping

about the same as I would

except

all the time.


Probably not proven.... but it makes enough sense to me.

[Drip Curl Magic]

researching.....

[Ganoderma]

Our bodies also build up a resistance to certain chemicals. Psilocybin mushrooms are a great example. What’s the reasoning behind resistance? is it because of the ways they are absorbed? Reactions? And what about other things that make us of MAOI's?

[billg]

In essence there are two reasons people build up resistance to chemicals. The first is rapid, and it's called receptor desensitisation; a process whereby a receptor that is hit with a large amount of the chemical that acts upon it becomes less sensitive to that chemical in the short term. This can be achieved for example by their being another receptor molecule that picks up the chemical messenger. This second receptor may then lead to a change in the first receptor which then decreases how active the first receptor is. In this way, strong, continuous activation of a neuron leads to a rapid decrease in activity.

After this, if stimulation is chronic like in drug abuse, a slower longer lasting mechanism occurs, called receptor down-regulation. Similar chemical signals act on the nucleus of the cell (rather than on the receptors themselves) - these signals result in the amount of the receptor on the surface of the cell to decrease; in other words, more receptors are recycled back into the cell, and fewer are put back out. Less receptors means the chemical or drug will have less of an effect, and also means that in the absence of the drug, the person will not function normally (in other words have withdrawal symptoms).