Some science behind the scenes
Any chemicals that are distributed via the blood stream to a receptor are called ‘ligands’. Ligands can be produced by our bodies – so naturally produced signals that help in the overall functioning of our body; or they can have been obtained from outside our bodies via drugs or food or similar. They have been eaten or breathed in, or injected into a vein or artery or a muscle or rubbed onto our skin or in some way wriggled into our bodies from outside.
Biochemists classify each ligand that binds to a cell into four main types:
A Full or partial agonist - binds to a receptor of a cell and triggers a response by that cell. If it is a ‘full’ agonist you get the full response. So if a ligand binds to a cell that is able to make you happy, you are not just happy you are really happy – euphoric. If it is a ‘partial’ agonist you do not get the full response, the function is perhaps a lower grade of activity than the full response. So instead of being really happy you are just pleasantly happy or not sad, instead of being really depressed you are just a bit sad.
An Antagonist - binds to a receptors but blocks the response and stops any more binding. These too can be full or partial So if a full ligand binds to the cell receptor controlling happiness, you feel nothing – neither happy nor sad. Functionally it may also mean you can’t wee or can’t poo or have difficulty remembering or learning, or counting, or being sensible or any number of the other functions we have. It is a function blocker. A function deactivator. If it is only partial it just has a partial blocking action
Personally I find this classification a little unhelpful. I prefer to think of the function as a function with a sort of sliding scale of activity. For example
The function covers happiness and sadness and all its extremes of emotion with a sort of slider on the scale to turn up or turn down the volume depending on the amount of ligand activity. At either end of the scale you have overdose proportions – full activity, whereas in between normal proportions – partial activity – reducing down to tiny little - homeopathic amounts – produces gradually smaller amounts of activity until everything balances out and you get nothing – no activity either way.
See also Intensity and Emotions and intensity.
I suspect that the volume is in part dependent on the frequency of the electrical signals if the signal is via the nervous system and if the chemical is carried by the blood stream by dose.
Some activities like happiness do us no harm when we overactivate them. If we agonistically over-activate the activity of pleasure, we will get total bliss. If we over-activate the function that gives us happiness or sadness, however, we could be driven into a morass of depression or a tumult of euphoria depending on whether the trigger is antagonistic or agonistic. Being euphoric once in a while may be quite nice [but see the problems of overload.] But there are obviously also some activities that if we over activate them they can cause us as much harm as if they were blocked.
In a natural environment I think the body uses antagonists to dampen down any activity that gets a bit out of control – it is a necessary regulator. For example, suppose we have a function or activity that helps cells to reproduce. If this activity goes haywire and cells start reproducing violently we say we have cancer. Antagonistic activity then helps to dampen this out of control reproduction, so if we have cancer, an antagonist applied correctly would help us. But if the antagonist blocks cell reproduction we die. So everything in nature has its use, it is only harmful if the balance goes wrong.
If external agents are introduced into our body that have unbalanced us, or we ourselves have somehow through what we have done produced an imbalance, all we may need to get us up and running again is a tiny tiny little jog in the right direction – a homeopathic dose. This is how homeopathy works and the substance may be an agonist or an antagonist – it depends on what activity we want triggering. In the example above with overactivation of cell reproduction, we would want to add a small dose of antagonist.
My granny [my Dad’s Mum] was a homeopathist and she used arsenic and all sorts of apparently poisonous substances to treat my dad and all his brothers and sisters when he was young. Sickness to her was a sign that one function was either over-activated, or under-activated, so you had to give it a tiny kick in the opposite direction to get it in balance. One truly minute dose was usually enough. For granny, no natural substance was a poison, at the wrong dose it certainly could be, but all substances by their agonist or antagonistic action had their uses.