Dopamine

Dopamine has many functions in the brain, including important roles in behavior and cognition (The mental process of knowing, including aspects such as awareness, perception, reasoning, and judgment), motor activity, motivation and reward, sleep, mood, attention, and learning.


Dopamine is commonly associated with the pleasure system of the brain, providing feelings of enjoyment and reinforcement to motivate a person proactively to perform certain activities. Dopamine has been shown to be involved in the control of movements, the signaling of error in prediction of reward.

Biosynthesis:
L-Phenylalanine - L-Tyrosine - L-Dopa - Dopamine - Noradrenaline - Adrenaline

Natural Dopamine Supplements:
L-Phenylalanine, L-Tyrosine, Dopa Mucuna (Mucuna Pruriens), L-Theanine, St John's Wort , B6

L-phenylalanine is found in most foods that contain protein such as beef, eggs, poultry, pork, fish, milk, yogurt, cheese, soy products (including soy protein isolate, soybean flour, and tofu), banana, certain nuts and seeds. Vegetables and juices contain small amounts of the free amino acid.

Good sources of tyrosine include dairy products, meats, fish, and beans.

A molecule of Tyrosine, a dopamine precursor:

Dopamine reuptake inhibition, expulsion

Cocaine and amphetamines inhibit the re-uptake of dopamine; however, they both influence separate mechanisms of action. Cocaine is a dopamine transporter blocker that competitively inhibits dopamine uptake to increase the lifetime of dopamine and augments an overabundance of dopamine (an increase of up to 150 percent) within the parameters of the dopamine neurotransmitters.

Like cocaine, amphetamines increase the concentration of dopamine in the synaptic gap, but by a different mechanism. Amphetamines are similar in structure to dopamine, and so can enter the terminal button of the presynaptic neuron via its dopamine transporters as well as by diffusing through the neural membrane directly. By entering the presynaptic neuron, amphetamines force dopamine molecules out of their storage vesicles and expel them into the synaptic gap by making the dopamine transporters work in reverse.

Cocaine has most effect on inhibiting reuptake, while amphetamine has most effect in increasing synthesis of dopamine.

For more on dopamine go to http://en.wikipedia.org/wiki/Dopamine

Article - Why dopamine freezes parkinson patients and drives drug addicts:http://www.physorg.com/news137429061.html

Methamphetamine and Dopamine video: http://www.youtube.com/watch?v=m7HvHp9V-e0