Monday, September 26, 2022

What Is Serotonin In The Brain

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Foods Arent The Only Things To Boost Serotonin

There are plenty of other options available that will increase serotonin levels. Drinks like green tea and probiotics help to boost serotonin.

While these drinks dont contain serotonin, other components within them assist with boosting serotonin levels.

Other foods containing Vitamin D are also good because Vitamin D activates tryptophan, which leads to increases in serotonin levels. Good sources of Vitamin D foods include cod liver oil, fortified orange juice, and many types of yogurt.

What Causes Serotonin Syndrome

A rise in serotonin levels can cause serotonin syndrome. This increase in serotonin can happen when a person:

  • Takes more than one medication that affects serotonin levels.
  • Recently started on a medication or increased the dose of a medication known to increase serotonin levels.
  • Takes too much of one serotonin-related medication, accidentally or on purpose.

Antidepressants are the most familiar medications that affect serotonin levels. Different classes of antidepressants include:

  • Selective serotonin reuptake inhibitors such as fluoxetine , citalopram , and sertraline .
  • Serotonin and norepinephrine inhibitors such as duloxetine and venlafaxine .
  • Bupropion .
  • Tricyclic antidepressants such as amitriptyline and nortriptyline .

Several other medications can affect the bodys serotonin use. These medications treat:

  • Severe pain: This pain is treated with medications including opioids like tramadol and oxycodone.
  • Coughing: Over-the-counter cough and cold medications containing dextromethorphan can be used to treat coughing.
  • Migraine headaches: These headaches can be treated with medicines called triptans.
  • : Drugs like ritonavir can be used to treat HIV/AIDS.
  • Anti-nausea medications: Metoclopramide and ondansetron .

Other factors may affect how your body regulates serotonin levels. These factors include using:

Seasonal Affective Disorder And Suicides

Dysfunctions in brain serotonin are implicated in many mental disorders, such as autism, Down’s syndrome, anorexia nervosa, anxiety, and depression. There are nearly 15,000 papers dealing with serotonin and various diseases ranging from alcohol addiction and autism to herpes zoster and dermatitis . The relationship between serotonin and depression is cited in over 23,000 papers, with 16.000 citations since 2000. Furthermore, a strong correlation exists between brain serotonin levels, depression, and suicide, with the first paper in this area written over 50 years ago . Those attempting suicide had significantly lower levels of 5-HIAA in the CSF compared to controls . PET studies indicate the 5-HT2A receptors are altered in depressed suicide attempters , and the receptor gene is changed in at-risk populations . A decrease in serotonin has serious consequences on normal brain homeostasis, both structural and functional, and influences a person’s desire to continue living. It is surprising to learn that sunlight has dramatic actions on the brain serotonin system of humans.

Figure 1.8. The evolutionary relationship between sunlight and the amino acid tryptophan and its major derivatives: serotonin, melatonin, auxin, and NADH. In addition, the connections of certain tryptophan-containing proteins are illustrated: chlorophyll, rhodopsin, and the 5-HT1A receptor. These relationships began in the earliest eukaryotic cells and continue in humans.

S. Athar, in, 2010

Serotonins Link To Autism Explained

This article is part of:

Serotonin, the brain chemical best known for its link to depression, may also be involved in autism.

Serotonin has many roles throughout the body, including in mood, sleep, appetite and sociability. In the intestines, it stimulates muscles involved in digestion; in the blood, it causes vessels to shrink or expand; and in the brain, it relays messages between neurons. Its levels in the brain are closely tied to depression. Many antidepressants work by increasing the levels of serotonin at neuronal junctions.

Tenuous ties between serotonin and autism first surfaced decades ago. In 1961, a study of 23 autistic people reported that 6 of them had an unusually high level of serotonin in their blood. Since then, researchers have consistently found that about one in four people on the spectrum has high blood serotonin.

That result is incredibly well replicated, says Jeremy Veenstra-VanderWeele, professor of psychiatry at Columbia University.

Motivated in part by these results, several research teams have tested antidepressants as a treatment for autism over the past 20 years with mixed results. Interest in serotonins role in autism has grown in the past five years, due in part to mouse studies that implicate the chemical in social behavior.

Heres what we know so far about serotonins role in autism.

These levels are highly heritable, suggesting that genetic factors control them.


Soexplain How Does Serotonin Impact Mood And How Is That Related To Mental Health

The serotonin pathways in the brain. The principal centres ...

The unsatisfying answer is researchers arent sure. While they can measure serotonin levels in the bloodstream, its impossible to measure them in the brain of a living person.

We cant say that serotonin impacts mood in a particular way, says Jonen. A lot of what we know is by inference and observation. Weve noticed that when serotonin levels are high, mood improves. But there are lots of other chemical processes happening in the bodyit might not be a one-to-one relationship. We dont know if people who are depressed stop making serotonin, if low levels of serotonin lead to depression, or if there are other factors that cause both depression and low serotonin.

Other potential causes include faulty serotonin receptors on cells or a lack of tryptophan, the amino acid from which serotonin is made.

Despite these lingering question marks, it is clear from research that balanced serotonin levels often lead to calm, focused, happy, and stable moods. When levels dip too far, well lets just say, its a different story. Low serotonin levels are mostly commonly associated with depression, as well as , panic disorder, obsessive-compulsive disorder, and excessive anger.

The Link Between Too Much Serotonin And Autism

High blood levels of serotonin are linked to autism spectrum disorder.

This biomarker occurs in 25% of all autistic children.

Interestingly, elevated blood levels of serotonin are also found in immediate family members who are not autistic.

The significance of this association is not clearly understood at this time, but another key to the puzzle may lie in the fact that children exposed to drugs that increase serotonin in utero have an increased risk of developing autism.

Organized Projections Of Neurons

The Stanford scientists focused on a region of the brainstem known as the dorsal raphe, which contains the largest single concentration in the mammalian brain of neurons that all transmit signals by releasing serotonin .

The nerve fibers, or axons, of these dorsal raphe neurons send out a sprawling network of connections to many critical forebrain areas that carry out a host of functions, including thinking, memory, and the regulation of moods and bodily functions. By injecting viruses that infect serotonin axons in these regions, Ren and her colleagues were able to trace the connections back to their origin neurons in the dorsal raphe.

This allowed them to create a visual map of projections between the dense concentration of serotonin-releasing neurons in the brainstem to the various regions of the forebrain that they influence. The map revealed two distinct groups of serotonin-releasing neurons in the dorsal raphe, which connected to cortical and subcortical regions in the brain.

Serotonin neurons in the dorsal raphe project to a bunch of places throughout the brain, but those bunches of places are organized, Luo said. That wasnt known before.

Can Diet Influence Our Supply Of Serotonin

It can, but in a roundabout way. Unlike -rich foods, which can directly increase your blood levels of this mineral, there are no foods that can directly increase your body’s supply of serotonin. That said, there are foods and some nutrients that can increase levels of tryptophan, the amino acid from which serotonin is made.

Protein-rich foods, such as meat or chicken, contain high levels of tryptophans. Tryptophan appears in dairy foods, nuts, and fowl. Ironically, however, levels of both tryptophan and serotonin drop after eating a meal packed with protein. Why? According to nutritionist Elizabeth Somer, when you eat a high-protein meal, you “flood the blood with both tryptophan and its competing amino acids,” all fighting for entry into the brain. That means only a small amount of tryptophan gets through — and serotonin levels don’t rise.

But eat a carbohydrate-rich meal, and your body triggers a release of . This, Somer says, causes any amino acids in the blood to be absorbed into the body — but not the brain. Except for, you guessed it — tryptophan! It remains in the bloodstream at high levels following a carbohydrate meal, which means it can freely enter the brain and cause serotonin levels to rise, she says.

What can also help: Getting an adequate supply of vitamin B-6, which can influence the rate at which tryptophan is converted to serotonin.

Supplements To Increase Serotonin In The Brain

The word nootropics might seem like a made-up term, but its used extensively in the medical community to describe a class of drugs that intend to enhance cognitive functioning in various methods.Supplements To Increase Serotonin In The Brain


Nootropics are substances that promote cognitive function, particularly by improving memory, concentration, and focus. Youve probably become aware of them as wise drugs or brain drugs. Nootropics are likewise referred to as nootropics, clever drugs, neuroenhancers, memory enhancers, cognitive enhancers, and intelligence enhancers.

Serotonin Syndrome Causes And Treatment

Serotonin syndrome, which is a type of serotonin toxicity, is when high levels of the chemical accumulate in the body. This is sometimes caused by taking two or more medications that raise levels, or combining medications with some herbal supplements. Abuse of illegal drugs, like LSD, cocaine, ecstasy and amphetamines can also cause this condition.

The most common serotonin syndrome symptoms are anxiety, restlessness, agitation, sweating and confusion. In more serious cases, it can also lead to health issues like muscle twitching, muscle stiffness, irregular heartbeat, high blood pressure, high fever and seizures.

Research also suggests high serotonin levels increase the risk of osteoporosis due to its effects on our bones. If you notice these symptoms, consult your healthcare provider and talk to him/her about having your levels tested.

For people dealing with this condition, serotonin syndrome treatment involves withdrawal from the drugs or medications that are causing your chemical levels to be too high. There are also medications that are used to block production of the neurotransmitter, such as Periactin.

How Does Serotonin Help With Memory Improvement

There are many memory improvement benefits with having normal or slightly elevated serotonin levels in the brain. One is that Serotonin is the precursor to the hormone, Melatonin. Melatonin is made in the pineal gland and is released at night to signal to your body that it is time to go to sleep. Getting enough sleep for your brain to fully recover is essential when it comes to moving information from short term memory to long term memory. 

In a study done by John Hopkins, they state the following three main points about Serotonin and those with early-onset signs of dementia or memory issues.

  • Lower serotonin transporter binding is observed in mild cognitive impairment versus controls in cortical, limbic, sensory and motor regions.
  • Reductions in the serotonin transporter were more statistically robust than cerebral atrophy in mild cognitive impairment compared to controls.
  • Lower serotonin transporter binding was associated with worse performance in verbal and visual-spatial memory in mild cognitive impairment.

Now this doesnt necessarily mean that having low levels of Serotonin causes dementia or Alzheimers but it does say that those with cognitive issues showed that they had low levels of Serotonin compared to control groups of healthy individuals.

More research still needs to be done to have a definitive answer as to whether or not serotonin alone can directly benefit healthy individuals brains when it comes to memory improvement.

Serotonergic System In Relation To Food Intake And Satiety

Concentration of brain serotonin is related to behavior and mood changes, anxiety, aggressiveness, depression, sleep, fatigue, and appetite suppression. Studies have shown that inhibition of 5-HT transporter reduces food intake and body weight gain. The serotonergic system shows control over hunger and satiety through various 5-HT receptors with different functions, and 5-HT1A, 5-HT1B, and 5-HT2C seem to be the most important receptors in this regard . The system also interacts with different pathways, precisely 5-HT2C, POMC, CART, and MC4, in regulating the energy balance.

Table 17.6. Role of Biogenic Amines and Neuropeptides in Obesity and Food Intake Behavior

Example of biogenic amines and peptideType/nature

J. Vernikos-Danellis, P.A. Berger, in, 1973

Too Much Serotonin: Take The Next Step


Serotonin is one of the most important of the feel-good neurotransmitters.

Too little is linked to depression, but too much serotonin is linked to a long list of side effects, may contribute to anxiety and autism, and can even be acutely dangerous.

Antidepressants usually work by increasing serotonin levels, but can elevate them too much.

This is the main cause of an excessively high serotonin level.

Avoid mixing antidepressants with other serotonin-boosting drugs or supplements as this will put you at risk for an elevated serotonin level.

Additionally, you can modulate serotonin synthesis with the right supplements.

If you are unsure whether your medications or supplements can be safely mixed, we urge you to talk to your doctor or pharmacist.

In the meantime, consult one of the reputable online drug interaction checkers found in our Mental Health Resources Guide.

Foods That Support Healthy Serotonin Function

Tryptophan, an important amino acid that humans can only obtain through diet, is the bodys precursor to serotonin. The World Health Organization recommends a daily tryptophan intake of 4 mg/kg of body weightfor a person weighing 150 pounds, thats about 272 mg of tryptophan a day. 

Foods containing high concentrations of tryptophan, according to the U.S. Department of Agricultures National Nutrient Database, include: 

  • Seeds and nuts, particularly pumpkin, chia, and sesame seeds
  • Eggs
  • Soy products including tofu, soy beans, and soy milk
  • Cheese, especially Parmesan, cheddar, and mozzarella
  • Oats and oat bran

Chocolate, bananas, and dried plums are additional sources.


Serotonin And Differentiation Of Hematopoietic Cells

The regulation of serotonin on differentiated hematopoietic cells has also been reported. Serotonin is an important regulator for the survival of red blood cells in vivo and that erythropoiesis is obviously impaired in mice with peripheral serotonin deficiency . Further analysis reveals that serotonin in the microenvironment acts as an antioxidant extrinsic effector to protect RBCs from senescence . Serotonin has also been shown to bind onto the surface of platelets and the conjugation of serotonin to the procoagulant proteins could stimulate platelet activation . Platelet-derived serotonin influences the differentiation of monocytes into dendritic cells and impairs the differentiation of DCs to T cells .

Outside The Nervous System

In the digestive tract

Serotonin regulates gastrointestinal function. The gut is surrounded by enterochromaffin cells, which release serotonin in response to food in the . This makes the gut contract around the food. Platelets in the veins draining the gut collect excess serotonin. There are often serotonin abnormalities in gastrointestinal disorders such as constipation and irritable bowel syndrome.

If irritants are present in the food, the enterochromaffin cells release more serotonin to make the gut move faster, i.e., to cause diarrhea, so the gut is emptied of the noxious substance. If serotonin is released in the blood faster than the platelets can absorb it, the level of free serotonin in the blood is increased. This activates 5-HT3 receptors in the chemoreceptor trigger zone that stimulate . Thus, drugs and toxins stimulate serotonin release from enterochromaffin cells in the gut wall. The enterochromaffin cells not only react to bad food but are also very sensitive to and cancer chemotherapy. Drugs that block 5HT3 are very effective in controlling the nausea and vomiting produced by cancer treatment, and are considered the gold standard for this purpose.

Bone metabolism

Organ development

Cardiovascular growth factor

Cardiac fibrosis

Several classes of target the 5-HT system, including some , , , , and antimigraine drugs, as well as, the psychedelic drugs and .

Low Serotonin And Insomnia

Sleep problems of all kinds the inability to fall asleep, sleep deeply, or stay asleep can be due to lack of serotonin.

Serotonin is a precursor to melatonin, the hormone responsible for managing your biological clock.

Of course, there are many causes for insomnia that have nothing to do with serotonin.

But according to Dr. Kharrazian, if melatonin supplements help you sleep, thats an indication that your insomnia is serotonin-related.

How To Increase Serotonin

Depression is known to be associated with chemical imbalances in the brain. While serotonin’s role in depression is more complex than an imbalance, it is believed to play a key role.

Increasing how much serotonin is in the brain appears to improve communication between brain cells, which in turn lifts mood and reduces symptoms of depression. This is why prescription antidepressant medications are used to treat clinical depression and other mood disorders.

There are also natural ways to increase serotonin levels. Everything from the food you eat to how much sunlight you get can affect how much serotonin your body has, as well as how effectively it can use it.

Can Alcohol Cause Anxiety

The long-term consequences of alcohol abuse can be a variety of health problems, including mental health disorders.

shows that people with alcoholism find it difficult to recover from traumatic events. This is possibly because of the effects of alcohol abuse, which can actually change brain activity.

Long-term heavy drinkers may be predisposed to developing an anxiety disorder. However, there is no evidence that moderate drinking will cause anxiety.

Increased anxiety is also a symptom of alcohol withdrawal. If youve consumed alcohol in large amounts for a long period of time and suddenly stop drinking, your anxiety can be aggravated by the side effects of alcohol withdrawal. Other symptoms of alcohol withdrawal include:

  • trembling hands

typically refers to two drinks a day for adult men and one for women. Older adults metabolize alcohol faster, so if youre in this age group, limit yourself to one alcoholic beverage per day. Ask your doctor if moderate alcohol consumption is suitable for you.

The benefits of alcohol consumption can sometimes be outweighed by the risks, which include:

  • depression
  • liver disease
  • cardiovascular damage

Alcohol affects everyone differently. It can cheer you up after a rough day or make you feel more sedated. Discuss these concerns with your doctor first to see if alcohol is safe for you.

Keep in mind that you may not safely drink alcohol if you have:

  • a low tolerance for drinking
  • anxious or aggressive tendencies
  • a mental health disorder

What Is The Link Between Serotonin And Depression

There are many researchers who believe that an imbalance in serotonin levels may influence mood in a way that leads to depression. Possible problems include low brain cell production of serotonin, a lack of receptor sites able to receive the serotonin that is made, inability of serotonin to reach the receptor sites, or a shortage in tryptophan, the chemical from which serotonin is made. If any of these biochemical glitches occur, researchers believe it can lead to , as well as obsessive-compulsive disorder, anxiety, , and even excess anger.

One theory about how develops centers on the regeneration of brain cells — a process that some believe is mediated by serotonin, and ongoing throughout our lives. According to Princeton neuroscientist Barry Jacobs, PhD, may occur when there is a suppression of new brain cells and that stress is the most important precipitator of depression. He believes that common known as SSRIs, which are designed to boost serotonin levels, help kick off the production of new brain cells, which in turn allows the depression to lift.

Also, researchers don’t know whether the dip in serotonin causes the depression, or the depression causes serotonin levels to drop.

medications that work on serotonin levels — SSRIs and SNRIs — are believed to reduce symptoms of depression, but exactly how they work is not fully understood.

Dangers Of Too Much Serotonin

Main serotonin pathways in the brain.

Always ask your doctor before taking any medication or supplement to increase low serotonin. Certain medications and supplements can raise serotonin levels too much, which can lead to serotonin syndrome.

The symptoms of serotonin syndrome range from unpleasant to life-threatening and can include sudden swings in blood pressure, seizures, and loss of consciousness.

Serious cases of serotonin syndrome can be fatal if left untreated. If you or a loved one is showing symptoms of serotonin syndrome, or go to the nearest emergency room.

How Are Dopamine And Serotonin Levels Affected By Various Drugs

Every type of drug you take affects the brain in one way or another. It most often affects how the brain communicates with the rest of the body. Most drugs interact with serotonin and dopamine.

The drugs that interact with serotonin will cause a persons happiness to be affected. Sometimes, it can be hyperactive happiness and joy while other times, the person can fall into deep depression.

The National Institute on Drug Abuse reports that drug abuse commonly affects dopamine and serotonin. When dopamine is manipulated, it has an effect on the following:

  • Motivation.
  • How a person is effected by events.

Drugs that have an effect on serotonin include:

  • Learning.

Increase In Brain Serotonin Signaling And Bone Mass

Serotonin once released outside the cells is inactivated by either metabolizing it through the enzymes or is taken back in the cells through a transporter to curtail its effect on the receptors. This metabolism of serotonin has long been utilized to cure patients with depression by elevating their extracellular concentration of serotonin in the brain and thereby increasing serotonin signaling. This raises the question of what effect an increase in serotonin signaling has on the bone mass. Selective serotonin reuptake inhibitors are a class of drugs that blocks the transporter HTT and increase serotonin signaling . Based on these effects, this class of drugs is prescribed to cure many psychiatric disorders associated with diminished serotonin signaling and their therapeutic actions are diverse, ranging from efficacy in the treatment of depression to panic disorders. The plethora of receptors and metabolic pathways for serotonin are candidates to mediate not only the therapeutic actions of SSRIs, but also their side effects . Richards et al. , while studying a cohort of community-dwelling adults, revealed that patients that were taking SSRIs had an increased risk of hip fractures. Because SSRIs have the ability to cross the bloodbrain barrier it raised the question as to the site of action of these drugs to produce their deleterious actions on bone.

Charles D. Nichols, Elaine Sanders-Bush, in, 2003

Serotonin Deficiency Diagnosis And Treatment

A serotonin blood test can measure levels of serotonin in the blood. However, doctors usually only use this test to check for serotonin-producing tumors. Doctors dont usually perform blood tests to assess serotonin levels because factors other than blood serotoninsuch as metabolism, the behavior of serotonin receptors, and hormonescan affect the bodys ability to process and use serotonin. Its possible for a person whose blood serotonin levels appear normal to have very little usable serotonin.

Instead of testing serotonin levels, doctors typically treat a persons symptoms. Depending on the symptoms you have, your provider may recommend tests to rule out other causes, such as hormone imbalances or a physical injury. Then they may recommend a medication that raises serotonin levels, such as an antidepressant. In some cases, providers may also recommend lifestyle changes such as exercise.

Serotonin deficiency is a complex issue. Lifestyle and psychological factors often play a central role. Moreover, symptoms of serotonin deficiency can affect a persons relationship and quality of life. Therapy can help in numerous ways. For people with depression related to low serotonin, a therapist can offer lifestyle management tips, a sympathetic ear, and help with relationship issues.

For help finding a therapist who can support you as you deal with low serotonin, .


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Role Of Serotonin In Anaphylaxis

In a comprehensive review48 of recent work on serotonin, Erspamer has discussed the role of serotonin in anaphylaxis.

In the dog serotonin probably plays no part as a chemical mediator of anaphylaxis.49 This is not true of other species. In the rabbit serotonin is released from blood platelets during anaphylactic shock.50, 51, 52 This causes an immediate rise in plasma serotonin.51 There is also an increase in the urinary excretion of serotonin metabolites.53 Furthermore, during anaphylaxis in the rabbit the amount of serotonin in whole blood falls from 3·26·0g to 0·8 g./ml., whereas the lung content of serotonin increases considerably from 3 to 22 g./g. This is caused by the trapping of platelets in the blood vessels of this organ.54 Pretreatment of the animals with heparin prevents the above effects and also the release of serotonin from platelets recovered from the blood of sensitised animals and exposed to antigen in vitro. Heparin will also inhibit the ability of rabbit platelets to adsorb serotonin55 from plasma in vitro.

An interesting observation which may eventually shed some light on the changes in tissue serotonin distribution provoked by anaphylaxis was made by Waalkes and Coburn.63 The intravenous administration of glycogen causes a marked fall in whole blood concentration of serotonin and a rise in lung serotonin content. As in anaphylaxis, this was brought about by the trapping of platelets in the pulmonary circulation.

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