Where are endorphins stored?

[Intense]

Me, intense?

No I was referring to the OP.

 

[Nagelfar]

...Seems weird to me that poppies would create such a chemical as a so-called 'defence mechanism'. Seems more like an incentive to me.

We're usually calling it thus against insects; which a dose that would be many times fatal to life of that size would not be to a "mega-fauna" such as a human (which is what we're technically classed as due to our respective size relative all other non-plant life on earth). In the same way that cocaine in the coca plant is an insecticide due to its anesthetic and stimulant properties killing insects, but not so for humans (though capable of killing humans in large concentrated doses too, just not as readily)

 

[Muzda Jonxx]

We're usually calling it thus against insects; which a dose that would be many times fatal to life of that size would not be to a "mega-fauna" such as a human (which is what we're technically classed as due to our respective size relative all other non-plant life on earth). In the same way that cocaine in the coca plant is an insecticide due to its anesthetic and stimulant properties killing insects, but not so for humans (though capable of killing humans in large concentrated doses too, just not as readily)

That makes sense, thanks for clarifying..

 

[Jabberwocky]

Do we have much knowledge on what mediates the pleasureable effects of orgasm, or what brain region(s) or cells are most involved?

Yes.

Dopamine - main driver

Serotonin m- balancing act -- increases pleasure and responsible for indicating post coital state by release of oxytocin -- too much = anorgasmia and lacy of sensation

nor-adenaline - adjunct to dopamine release

Oxytocin (post orgasm)

Prolactin high levels causes anorgasmia and low libido due to it's action on dopamine -- and vice versa

dopamine agonists can eliminate male refractory time and allow for multiple orgasm


Nucleus Accumbens, hypothalamus, explicitly at orgasm ( also insular & cingulate cortex, hippocampus during pre-orgasm)

 

[aced126]

Yes.

Dopamine
Serotonin
nor-adenaline
Oxytocin (post orgasm)

High Prolactin causes anorgasmia and low libido due to it's action on dopamine -- and vice versa

dopamine agonists can eliminate male refractory time and allow for multiple orgasm

I thought dopamine regulates prolactin secretion (D2 agonism at prolactin cells), not the other way round.

 

[Jabberwocky]

I thought dopamine regulates prolactin secretion (D2 agonism at prolactin cells), not the other way round.

Prolactin lowers testosterone and increases estrogen production -- both inhibit dopamine release

I found a citation once about a direct action of prolactin -- ill have to find it

 

[aced126]

Prolactin lowers testosterone and increases estrogen production -- both inhibit dopamine release

I found a citation once about a direct action of prolactin -- ill have to find it

This is weird...it would result in positive feedback and more release of prolactin surely?

 

[Jabberwocky]

I thought dopamine regulates prolactin secretion (D2 agonism at prolactin cells), not the other way round.

Found it:

" The hypothalamic dopaminergic neurons, which provide DA to the anterior pituitary gland, are themselves regulated by feedback from PRL through a 'short-loop feedback mechanism'"

http://www.ncbi.nlm.nih.gov/pubmed/18477617

and

"[h=1]Prolactin Regulates Tuberoinfundibular Dopamine Neuron Discharge Pattern: Novel Feedback Control Mechanisms in the Lactotrophic Axis"[/h]
http://www.jneurosci.org/content/32/23/8074.full