Dopamine is commonly known as one of the “happy hormones”, with three other key molecules – serotonin, oxytocin and endorphin also belonging to this group. A vital neurotransmitter, dopamine is involved in promoting good moods and pleasure, by relaying signals between neurons – the specialised nerve cells in the brain and spinal cord.
Also Read: Serotonin: Structure, Crucial Functions And Adverse Effects
The majority of dopamine is synthesized in many different segments of the brain and is released into blood flow by the hypothalamus, upon coming across anything that triggers good and positive thoughts. Dopamine plays a central role in the motivation-reward-reinforcement cycle, for example, it is released when a person who is fond of chocolate pastries sees some delicious fudge brownies at a store and the sense of satisfaction is attained upon taking measures to buy one and eat it.
Often referred to as the “feel-good hormone”, dopamine, aside from elevating feelings of motivation, reward, arousal, also regulates motor control, movement, decision-making, stress response and even insulin activity. These operations are facilitated by dopamine working in association with other key hormones of serotonin and adrenaline, which are also neurotransmitters.
Dopamine And Its Structure:
Dopamine was successfully synthesized by two renowned British chemists George Barger and James Ewens, for the first time in the year 1910 in London, England. Following this, the presence of dopamine in the human brain was determined by Katherine Montagu, a distinguished British researcher, in 1957. The function of dopamine as a neurotransmitter was conclusively established by two Swedish neuropharmacologists – Arvid Carlsson and Nils-Ake Hillarp, from late 1957 to 1958. For his significant contribution towards decoding the pivotal role of dopamine in the human body and identifying that dopamine was not merely a precursor for adrenaline and noradrenaline but a neurotransmitter in itself as well, Arvid Carlsson was awarded the Nobel Prize In Physiology Or Medicine in the year 2000.
Dopamine derives its name from its basic structure as a monoamine with the precursor L-dopa, in the chemical synthesis protocol outlined by Barger and Ewens. It is an organic compound that belongs to the catecholamine and phenethylamine groups. A dopamine molecule comprises a catechol component – a benzene ring with two hydroxyl side units, having one amine group affixed by means of an ethyl chain. Dopamine has a molar mass of 153.181 g/mol (grams per mole), with the chemical formula – C8H11NO2.
Functions Of Dopamine:
Dopamine is involved in carrying out various key operations in the body, such as:
- Fostering good moods
- Encouraging happiness and satisfaction
- Improving alertness, focus and productivity
- Sustaining motivation, active interest and arousal
- Supporting optimal blood circulation
- Promoting rational decision-making skills and practical choices
- Regulating body movement and control of motor neurons
- Ensuring normal functioning of the pancreas and boosting insulin activity
- Uplifting deep sleep and rest at night and preserving optimal sleep-wake cycles
- Augmenting the functioning of the heart, kidneys and digestive system
- Helping cope with stress by mediating cortisol effects
Also Read: Cortisol: Structure, Crucial Functions, Adverse Effects
Adverse Effects Of Hormonal Imbalance In Dopamine:
Low Levels:
Since dopamine promotes motivation and interest to perform any task, low levels of this hormone result in poor moods and trigger negative emotions of anger, frustration, worry, nervousness and irritability. It also invariably leads to decreased concentration and memory, lack of enthusiasm, problems with the smooth and vigorous motion of hands, legs and mobile body parts and even hampered coordination and control.
Moreover, insufficient amounts of dopamine prompt lethargy, tendency to fall asleep and fatigue, while disorders like insomnia give rise to low dopamine levels in the system. Depression and Parkinson’s disease are linked with reduced amounts of dopamine.
High Levels:
Dopamine in ideal concentrations enriches moods and positive feelings, however, in very high amounts, it can trigger severe euphoria, hallucinations, delusions, mania, such as the symptoms seen in bipolar disorder and cyclothymic disorder.
In addition, too much dopamine circulating in the body instigates chronic conditions of obesity, schizophrenia and even induces addictive sensations, leading to uncontrolled consumption of alcohol, tobacco, drugs or indulging in harmful pursuits. It is hence important to keep dopamine levels in the system under control for optimal brain function, mental wellbeing and nervous system activity.
