Serotonin is a neurotransmitter that is responsible for your happiness! Most anti-depressants focus on the production of serotonin.
- Introduction:What is Serotonin?
- Beneficial Effects of Serotonin
- 1) Serotonin Affects Heart Function
- 2) Serotonin Induces Intestinal secretions
- 3) Serotonin Helps Control Body Temperature and Breathing
- 4) Brain Serotonin Can Affect Your Mood
- 5) Serotonin Contracts Vascular Muscles
- 6) Serotonin May Impact Bone Regulation
- 7) Serotonin Increases Hypertension
- 8) Serotonin Affects Depression
- 9) Serotonin Impacts Anorexia Nervosa
- 10) Serotonin Impacts Attention-Deficit Hyperactivity Disorder
- 11) Serotonin Affects Carbohydrate-Craving And Obesity
- 12) Serotonin May Play A Role In Kidney Activity
- Technical Section
Introduction:What is Serotonin?
Serotonin, also called 5-Hydroxytryptamine (5-HT), is a biochemical messenger and regulator, synthesized from the essential amino acid L-Tryptophan.
In humans, it is found primarily in the central nervous system, gastrointestinal tract, and blood platelets.
It mediates several important physiological functions including neurotransmission, gastrointestinal motility, hemostasis, and cardiovascular integrity (R).
Beneficial Effects of Serotonin
1) Serotonin Affects Heart Function
5-Hydroxytryptamine can be considered as a significant circulating hormonal factor implicated in normal cardiovascular function either by acting directly on heart cells or by stimulating chemosensitive nerves from the heart (R).
Patients with carcinoid tumors (rare slow growing cancers) have high levels of this regulator associated with arrhythmia, leading to heart block or to valvular fibroplasia (R).
Also, mouse embryos grown in the presence of either a high concentration of 5-Hydroxytryptamine or Serotonin-specific reuptake inhibitors show a decreased proliferation of myocardium, cardiac mesenchyme, and endothelium (R).
2) Serotonin Induces Intestinal secretions
The secretory effects of 5-HT are mediated through different receptors: It induces secretion across human ileal mucosa, whereas a receptor of the 5-HT2A subtype appears to mediate the effect in the human sigmoid colon (R).
3) Serotonin Helps Control Body Temperature and Breathing
5-HT-producing cells in the mouse brain play an essential role in maintaining a healthy balance in body temperature and breathing (R).
Neurons in all of the nuclei that govern respiratory control have serotonin neurons (R).
4) Brain Serotonin Can Affect Your Mood
Acute tryptophan depletion (ATD) can result in lower mood and increase in irritability or aggressive responding.
Overall, studies manipulating tryptophan levels support the idea that low 5-Hydroxytryptamine levels can predispose subjects to mood and impulse control disorders.
Higher levels of 5-HT may help to promote more constructive social interactions by decreasing aggression and increasing dominance (R).
5) Serotonin Contracts Vascular Muscles
5-HT causes contraction of the vascular smooth muscle cells in most blood vessels studied in the lab (mainly due to the activation of S2-serotogenic receptors) (R).
The original intent of investigating 5-HT was for its vasoconstrictor effects. Early studies in dogs established a triphasic response to serotonin when injected intravenously (R).
When released from activated platelets, 5-HT can induce vasoconstriction in most large arteries, large veins, and venules.
6) Serotonin May Impact Bone Regulation
5-HT receptors have been identified in all the major bone cell types (osteoblasts, osteocytes, and osteoclasts) (R).
Evidence suggests that SSRIs (Selective Serotonin Reuptake Inhibitors) are associated with reduced bone mass, increased bone loss, and increased risk of fractures (R).
7) Serotonin Increases Hypertension
Several mechanisms were proposed to explain this including direct vasodilation, inhibition of adrenergic input, and stimulation of central areas contributing to correction of vasomotor tone.
8) Serotonin Affects Depression
Alterations in the serotogenic neuronal function in the central nervous system occur in patients with major depression, which can be evidenced by the reduced concentration of 5-HT in the postmortem brain tissue of the depressed.
9) Serotonin Impacts Anorexia Nervosa
5-Hydroxytryptamine is involved in almost all the behavioral changes observed in Anorexic patients.
10) Serotonin Impacts Attention-Deficit Hyperactivity Disorder
In one controlled trial, families were studied to determine the link between the serotogenic system and Attention-Deficit Hyperactivity Disorder (ADHD). Preliminary data suggested an important role of the 5-HT system in the development of ADHD (R).
11) Serotonin Affects Carbohydrate-Craving And Obesity
5-HT-releasing brain neurons are unique in that the amount of neurotransmitter they release is normally controlled by food intake:
12) Serotonin May Play A Role In Kidney Activity
In kidney injury, tissue damage occurs and platelet activation is observed. Recent studies suggest that some factors, such as 5-Hydroxytryptamine, are released into microenvironment upon platelet activation following kidney injury (R).
- Various agents can inhibit 5-HT reuptake, including cocaine, dextromethorphan (an antitussive), tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs).
- In animals including humans, 5-Hydroxytryptamine is synthesized from the amino acid L-tryptophan by a short metabolic pathway consisting of two enzymes: tryptophan hydroxylase and aromatic amino acid decarboxylase (R).
- 5-HT is produced in two steps. The essential amino acid tryptophan is hydroxylated to 5-hydroxytryptophan (5-HTP) by tryptophan hydroxylase. In a second step, 5-HTP is decarboxylated to form 5-HT (R).