Parkinson’s disease (PD) is believed to be caused by a deficiency of dopamine. Dopamine is a neurotransmitter, a chemical messenger between nerve cells in the mammalian brain. People with Parkinson’s Disease (PD) suffer increasing motor behavior impairment, usually at an older age. The primary symptoms include: muscular rigidity, resting tremor, difficulty with movement initiation (bradykinesia), slowness of voluntary movement, difficulty with balance, and difficulty with walking. This disease was named after the English MD. James Parkinson, who in 1817 was the first person to describe these symptoms as ‘the shaking palsy’,.
Dopamine research has enhanced scientists’ understanding of how diseases and addictions originate and develop. This understanding is leading to new treatment possibilities. Drugs, which act primarily as dopamine receptor agonists or antagonists can, serve as important clinical tools. Dopaminergic neurotransmission can mediate or modulate behaviors ranging from ambulation and stereotypy to self-stimulation, TOP conditioned avoidance responding, feeding and drinking.
D opamine is a biogenic amine synthesized in the hypothalamus, in the arcuate nucleus, the caudate, and various areas of the central and peripheral nervous system. It has been widely established that dopamine and its agonists play an important role in cardiovascular, renal, hormonal, and central nervous system regulation through stimulation of alpha and beta-adrenergic and dopaminergic receptors. There are several agonists of dopamine-2 (DA 2 ) dopaminergic receptors, such as bromocriptine, pergolide, lisuride, quinpirole, and carmoxirole, which inhibit norepinephrine release and produce a decrease in arterial blood pressure; in some cases, bromocriptine and pergolide also reduce heart rate.
A number of psychiatric disorders are associated with imbalances with dopamine, particularly schizophrenia, Parkinson’s disease, and mood disorders, including certain types of depression. Dopamine may also be involved in restless legs syndrome.
Dopamine is just one of many neurotransmitters used for communications between brain cells known as neurons. Neurotransmitters convey a nervous impulse across the gap that separates one neuron from another. After the signal has been passed along, the neurotransmitters diffuse away, are actively dismantled by enzymes or are reabsorbed by protein complexes called transporters on the surface of the originating neuron. “It’s known that the adenosine receptor and the dopamine receptors are present in some of the same areas of the brain, and sometimes even on the same cell. This fits in perfectly with our idea that dopamine fights against the tendency of adenosine to promote sleep,”
Benefits of dopamine
Dopamine is critical to the way the brain controls our movements and is a crucial part of the basal ganglia motor loop. Shortage of dopamine, particularly the death of dopamine neurons in the nigrostriatal pathway, causes Parkinson’s disease, in which a person loses the ability to execute smooth, controlled movements.
In the periphery, physiological dopamine increases renal blood flow, decreases renal resistance and acts on the kidney tubule to enhance natriuresis and diuresis. The loss of dopamine function may be involved in the deterioration in kidney function associated with ageing and may have a role in the pathogenesis of hypertension and diabetes.
Dopamine is used primarily for the treatment of hypotension that is not secondary to hypovolemia. Dopamine, Little explains, triggers the actions required to repeat previous pleasures. It’s not only involved in drug users’ “high” – it helps drive us to eat, work, feel emotions, and reproduce. Normally, when something pleasurable happens, dopamine neurons pump the chemical into the gaps between themselves and related brain cells. Dopamine finds its way to receptors on neighboring cells, triggering signals that help set off pathways to different feelings or sensations.
Dopamines are generally prescribed to treat Parkinson’s disease. However, in some people there may be a relationship between restless legs syndrome (RLS) and abnormalities in how the body produces or uses dopamine. A health professional may prescribe medication as treatment for continuous RLS symptoms that frequently disturb sleep, in which case dopamines are usually the first choice.
Schizophrenia has also been found to be hereditary. This biological disorder of the brain is a result of abnormalities, which arise early in life and disrupt the normal development of the brain. These abnormalities involve structural differences between a schizophrenic brain and a healthy brain. Schizophrenic brains tend to have larger lateral ventricles and a smaller volume of tissue in the left temporal lobe in comparison to healthy brains. The chemical nature of a schizophrenic brain is also different in the manner the brain handles dopamine, a neurotransmitter. Neurotransmitters transmit impulses between neurons.