I explained in my post largely what you are saying by going into details about the pineal gland in your brain. Without it your brain wouldnt function. No one knows where its energy comes from but it sends dopamine (a type of plasma) around your brain keeping it functioning.
Dopamine is not a type of plasma....
Neurons make their own dopamine. When the dopamine level in a neuron is low, a copy of the portion of DNA that codes for "Dopamine" is made. This copy is one of the forms of RNA. This goes into the cell body, where ribosomes help attach proteins in a chain. There are 4 basic proteins, each of them correspond to one of the 4 different codes in DNA. Thus, you can create any protein in any body - plant or animal - using this coding system. So, the code for "dopamine" gets copied and translated into dopamine. Several dopamine molecules are packaged into tidy little bubbles and are transported to the synapse, where it is needed. It is not made solely by the pineal gland.
Dopamine is a neurotransmitter. It is released from one neuron at a synapse whenever the neuron receives an electrical signal. The dopamine interacts with receptors in the cell membrane of the next neuron, causing an influx of Na+ across the cell membrane, which propagates the electrical signal along
that neuron. Dopamine then is released from the receptors, and is absorbed either into the cell once again, via re-uptake pathways, or released into the blood stream.
I also know where the pineal gland would get its energy from. It's not a huge secret - sugars. Animal cells like ours burn sugar as an energy source. This allows them to perform various functions, like protein building and signal transmittion.
All this is from 1st year level cellular biology. It wouldn't be too much effort to go and find some factual information yourself...