Page 1

December 10, 2012


Krista Filek, Marissa Stelzer, Grace Doty, Lauren Williams

A neurotransmitter is a chemical messenger that carries, boosts and modulates signals between neurons and other cells in the body.

Neurotransmitters are chemicals that live inside brain cells (neurons). They are stored in sacks just by the synapse at the end of the neuron’s axon.

Functions? The functions of serotonin are numerous. It involves control of appetite, sleep, memory and learning, temperature regulation, mood, behavior (including sexual and hallucinogenic behavior), cardiovascular function, muscle contraction, endocrine regulation, and depression. Serotonin also regulates many other processes such as carbohydrate cravings, sleep cycle, pain control and appropriate digestion.

Excitatory or Inhibitory? Serotonin is an inhibitory neurotransmitter, meaning it does not stimulate the brain. Serotonin levels balance any excessive excitatory neurotransmitters firing in the brain. If one uses stimulant medications or caffeine daily, it can cause depletion of serotonin.

What in the body does it affect? About 80% of our body's total serotonin is in the enterochromaffin cells - where it regulates intestinal movements. The rest is synthesized in neurons in the central nervous system. Serotonin can affect the function of the heart, muscles, and element in the endocrine system. It is said Serotonin may also play a role in regulating milk production in the breast, and Serotonin defects could be a cause of Sudden Infant Death Syndrome (SIDS).


What happens if there is too much or too little? Changes in amount of serotonin levels may affect mood. Serotonin is used to help the brain function normally, so a person with normal serotonin levels feels happy when conditions allow, and feel other emotions when happiness is not appropriate. If an individual has low levels of serotonin, they may feel distresses, have high anxiety, feel depressed, and have mood changes. If an individual has a high amount of serotonin, they may feel sleepy and inhibition of normal mood elevation and depression, also ones immune system will weaken.

Interesting Facts? 1) Scientists think that falling in love can affect your serotonin levels. A study done found that students who had recently fallen in love had 40% less serotonin in their blood. 2) Serotonin could play a role in why we love chocolate– chocolate contains tryptophan, which is a chemical that the brain uses to make serotonin. High levels of serotonin can make us feel really good. 3) Serotonin levels change with the seasons - serotonin transporter protein, a brain chemical that lowers serotonin levels around brain cells, is more active during the winter months - meaning that serotonin levels are lower. Researchers from the University of Toronto and the Medical University of Vienna believe that this mechanism explains why some people feel miserable during the winter

Diseases/ Disorders? When the brain produces low levels of serotonin, such signals become much more infrequent and shorter-lived, which produce psychiatric diseases including depression and anxiety, obsessive-compulsive disorder, and addiction. Researchers have found that low levels of serotonin turn individuals toward depression. Serotonin also plays a role in anxiety; individuals with low serotonin levels are more likely to experience anxiety to an unusual degree. With an abnormal amount of this neurotransmitter, one can feel very uncomfortable, leading them to obsess about particular issues or concerns. The obsession results in a compulsive behavior. serotonindeficient mice share the traits related to addiction, leading researchers to conjecture that individuals born with "addictive personalities" might well be serotonin deficient.

2 Medications/ Drugs? Selective serotonin inhibitors (SSRI) are used to suppress depression. SSRI alter the function of neurons that release serotonin by blocking the reuptake of serotonin back into the cell. This causes the serotonin level to increase in any part of the nervous system that uses serotonin as a chemical signal between cells. SSRIs is the drug of choice because they have to fewest side effects. Prozac is not only used to treat depression but people who lack selfesteem, fear rejection and the lack the ability to experience pleasure. Prozac prevent neurons from taking serotonin out of the synapses for recycling purposes. Unfortunately, although these SSRIs are effective in treating depression and are the least toxic of the antidepressants, they do produce some harmful side effects. Some have defined the presence of certain side effects due to SSRIs as "serotonin syndrome". To treat serotonin-related disorders, researchers have developed serotonin-increasing drugs that help the brain function more normally and decrease symptoms associated with low serotonin.

SSRI approved to treat depression • Citalopram (Celexa) • Escitalopram (Lexapro) • Fluoxetine (Prozac, Prozac Weekly, Sarafem) • Paroxetine (Paxil, Paxil CR, Pexeva) • Sertraline (Zoloft) • Fluoxetine combined with the atypical antipsychotic

For further information visit:http://


pictures: %253D2009%25252F12%25252FSerotonin1.jpg&w=450&h=337&ei=kDvCUL3iATVyAGryoCYBA&zoom=1&iact=hc&vpx=512&vpy=170&dur=369&hovh=172&hovw=231&tx=148&ty=76&sig=113976857079100892769&page=1&tbnh =137&tbnw=184&start=0&ndsp=21&ved=1t:429,r:3,s:0,i:161 S5UGBuLlvpI/AAAAAAAAA7k/Bk6mmY8zXXg/s400/happy%252Bserotonin.jpg&w=400&h=279&ei=kDvCUL3iATVyAGryoCYBA&zoom=1&iact=rc&dur=304&sig=113976857079100892769&page=1&tbnh=141&tbnw=203&start=0&ndsp=21&ved=1t:429,r:14,s:0,i: 194&tx=143&ty=65 %253D2009%25252F12%25252FSerotonin2.jpg&w=450&h=337&ei=kDvCUL3iATVyAGryoCYBA&zoom=1&iact=rc&dur=275&sig=113976857079100892769&page=1&tbnh=137&tbnw=178&start=0&ndsp=21&ved=1t:429,r:1,s:0,i: 155&tx=130&ty=58


Serotonin p 7  

Neurotransmitter Serotonin project