Synthesis And Function Of The Dopamine Transporter

Cocaine influences dopamine, norepinephrine and serotonin neurotransmission by inhibiting their reuptake. Pimozide, alpha-flupenthixol, perphenazine and chlorpromazine, all dopamine antagonists, were used to pre-treat rats in an attempt to demonstrate the reinforcing effects of dopamine.

Of the six most common neurotransmitters, dopamine is probably the one people know the most about. Dopamine is involved in controlling the reward and pleasure system in the brain. It allows us to recognize rewards and helps give us the ability to go after them. Learning, behavior, and cognition are also affected by dopamine levels. As with anything, if you have an imbalance, then bad things can happen. Parkinson’s disease can be caused by low dopamine amounts. People who have low dopamine levels can be addicted to substances easier.

Dopamine is produced in the substantia nigra, as well as in the adrenal glands and is transmitted to the basal ganglia along a connecting neural

Alzheimer disorder is an major nervous condition that present in irreparable loss of neuron in the cortex and hippocampus of the brain. The recurrence of the disease is 7% of people above 65 years old and 40% of individual above 80 years old. Patients commonly have issues in decision making, remembrance, and judgment. Pathological lineaments are specified as loss of neuron, extracellular senile plaques include peptide β-amyloid. Diagnosis is established on neurological feedback to rule out other reasons by using autopsy. Dopamine as neurotransmitter has an important part in etiology of Alzheimer disease and it is reduced in this disease.[3]

Information from the nigra cells passes through the synapses with the aid of a specific hormone, dopamine, which is a significant chemical transmitter in the brain. Because the existence of dopamine is essential to the function of the substania nigra, it is also essential for the various muscular activities controlled by the striatum, such as walking, balance, etc. (16).

Some dopaminergic (i.e., dopamine-releasing) neurons run from the substantia nigra to the corpus striatum; their loss gives rise to the clinical manifestations of Parkinson's Disease (Korczyn 1994); others, involved in the rewarding effects of drugs and natural stimuli, run from the mesencephalon to the nucleunucleus accumbens.

Over the years, experiments have produced evidence to suggest that dopamine plays a role in the development of Schizophrenia (Howes, McCutcheon, & Stone, 2015). Dopamine is a neurotransmitter that is produced in the substantia nigra and ventral tegmental regions of the brain. The belief that dopamine was involved in Schizophrenia arose after multiple studies performed with compounds produced an increase in extracellular concentrations of dopamine (Lieberman, Kane, & Alvir, 1987). The patients that were administered these compounds had similar symptoms to those observed from patients who were diagnosed with Schizophrenia (Lieberman et al., 1987).

Sex chromosomes can apply impacts free of sex steroid hormones on the advancement and upkeep of the dopamine framework.

The substrate L-DOPA showed a Vmax of 2.9*〖10〗^(-4) μmol/min with Tyrosinase, and a Km of 2.17*〖10〗^(-4) μmol (Figure 17). On the other hand D-DOPA showed a Vmax of 4.14*〖10〗^(-4) μmol/min and a Km of 5.44*〖10〗^(-4)

Performed in the practical was an experiment which was used to determine the number of dopamine D1 receptors in the striatum of a rat, along with the binding affinity of these receptors. In the total receptor binding experiment, the 3H-SCH 23390 was added to homogenised rat striatum tissue and Tris ion buffer in descending concentrations of 3H-SCH 23390. No flupentixol was added to these experiments. The lack of flupentixol allowed the binding of both specific binding to the D1 receptor and the non-specific binding to other binding sites to occur. The results in this experiment were as predicted.

The D2 Receptor of dopamine has an extremely important function in the nervous system. The D2 receptor is found as metabotropic which means it is coupled with a G-Protein Linked Receptor. It is found pre-synaptically as D2Sh which is also known as an autoreceptor. The D2Sh isoform of D2 receptor can regulate neurotransmission as well as affect synthesis, storage, and release of dopamine into the synaptic cleft. The heteroreceptor isoform of D2 receptor is known as D2Lh which

The pathways of dopaminergic called dopaminergic projections; has a group of neurons located in the brain that produces and releases the dopamine defined as a neurotransmitter (Le Moal, 2013). The neurons present in the dopamine have axons that run through the whole extent of the pathway and it named as dopamine neurons. Sometimes, mesocortical and mesolimbic pathways can be mentioned as the mesocorticolimbic pathway or system.The mesolimbic pathway has dopaminergic projections which release dopamine from the ventral tegmental area present in the midbrain to the ventral striatum (has nucleus accumbens and olfactory tubercle). This pathway has a role in emotion and reward systems. However, dopamine produces in the mesolimbic brings about pleasure

Parts of the brain that govern specific functions are: cerebellum-coordination and hippocampus-memory. Information is relayed from one area to another thru complex circuits of interconnected neurons, via electrical impulses called neuron transmission. This process involves a variety of chemical substances called neuron transmitters. One such neuron transmitter is called dopamine. Dopamine is an amine essential to normal nerve activity in the brain. Normally, dopamine is released by a neuron into the synapse

The University of Utah conducted a study and created a simulation called “Mouse Party” and shows how drugs cross the membrane in the brain and show the effects that the drugs have. For example, in the “Mouse Party” simulation, one of the dugs tested was cocaine. The simulation first states that dopamine transporters main function is to remove dopamine from the synaptic cleft when their job is finished. It then goes on to explain that when cocaine enters the system, the drug blocks the dopamine transporters; when this blockage occurs, the dopamine left in the synaptic cleft has no option but to bind to the receptors multiple times over which in returns over stimulates the cell. The simulation also explains that cocaine focusses in the reward pathway and is also in the section of the brain that controls voluntary movements, which explains why cocaine abusers are twitchy and cannot sit still for a certain period of time. (University of Utah Genetic Science Learning Center Mouse Party 2013). With the different drugs, different transport mechanisms, bulk, active, and passive, were used to transport the drug from the outside of the cell to the inside of the

Cocaine, on the other hand, has been found to have a profound effect on increased dopamine activity. Kennedy & Hanbauer (1983; cited in Karch, 2007) found a strong correlation between cocaine binding and the inhibition of dopamine uptake, and therefore proposed that dopamine transporters are binding sites for cocaine. Such research, which correlates strong reinforcing properties of cocaine with inhibition of dopamine transporters, suggests that cocaine has a more significant affect upon dopamine, than than it has upon serotonin and noradrenaline. The excessive role of dopamine can explain the high degree of pleasure that users of cocaine experience, as well as depression and cravings, which follow.