Seretonine
 

Dear All
AOA


I would like you all to share ur knowledge about " Seretonine: and Epinorphin"
What are these two.


Regards



Abdul Salam Khan.

[B]EPINEPHRINE[/B]

Epinephrine is also called adrenaline and is secreted by the adrenal glands. it is used as a medicine for patients where all other forms of resuscitation have failed and is injected directly into the heart.
Epinephrine plays a central role in the short-term stress reaction—the physiological response to threatening, exciting, or environmental stressor conditions levels. It is secreted by the adrenal medulla. When released into the bloodstream, epinephrine binds to multiple receptors and has numerous effects throughout the body. It increases heart rate and stroke volume, dilates the pupils, and constricts arterioles in the skin and gut while dilating arterioles in leg muscles. It elevates the blood sugar level by increasing catalysis of glycogen to glucose in the liver, and at the same time begins the breakdown of lipids in fat cells. epinephrine has a suppressive effect on the immune system.
Epinephrine is used as a drug to increase peripheral resistance via alpha-stimulated vasoconstriction in cardiac arrest and other cardiac dysrhythmias resulting in diminished or absent cardiac output, such that blood is shunted to the body's core. This beneficial action comes with a significant negative consequence—increased cardiac irritability—which may lead to additional complications immediately following an otherwise successful resuscitation. Because of its suppressive effect on the immune system, epinephrine is used to treat [B]anaphylaxis[/B] and [B]sepsis[/B]. Allergy patients undergoing immunotherapy may receive an epinephrine rinse before the allergen extract is administered, thus reducing the immune response to the administered allergen. It is also used as a bronchodilator for asthma if specific beta2-adrenergic receptor agonists are unavailable or ineffective. Adverse reactions to epinephrine include palpitations, tachycardia, anxiety, headache, tremor, hypertension, and acute pulmonary edema.

[B]SEROTONIN[/B]

In the central nervous system, serotonin is believed to play an important role in the regulation of body temperature, mood, sleep, vomiting, sexuality, and appetite. [B]Low levels of serotonin have been associated with eight disorders, notably clinical depression, obsessive-compulsive disorder (OCD), migraine, irritable bowel syndrome, tinnitus, fibromyalgia, bipolar disorder, and anxiety disorders[/B].If neurons of the brainstem that make serotonin – serotonergic neurons – are abnormal, there is a risk of sudden infant death syndrome (SIDS) in an infant.

simply saying:serotonin is a neuro transmitter which is released from synaptic vesicles at the neuron endings in order to pass the nerve impulse.

where as epinephrine is a hormone.

[B][SIZE="4"]Serotonin (5-HT)[/SIZE][/B]

Serotonin is synthesized extensively in the human gastrointestinal tract (about 90%),[1] and the major storage place is platelets in the blood stream.

In the body, serotonin is synthesized from the amino acid tryptophan by a short metabolic pathway consisting of two enzymes – tryptophan hydroxylase (TPH) and amino acid decarboxylase (DDC). The TPH mediated reaction is the rate limiting step in the pathway. TPH has been shown to exist in two forms; TPH1, found in several tissues and TPH2, which is a brain specific isoform. There is evidence that genetic polymorphisms in both these subtypes influence susceptibility to anxiety and depression (Nash et al 2005; Zhang et al 2005). There is also evidence that ovarian hormones can effect the expression of TPH in various species, suggesting a possible mechanism for postpartum depression and premenstrual stress syndrome (Hiroi et al 2006). The gut secretes over 95% of the body's serotonin.

Serotonin (5-HT) receptors are also used by other psychoactive drugs, including LSD, DMT, and psilocybin, the active ingredient in psychedelic mushrooms.

In the field of neurochemistry, 5-HT receptors are receptors for the neurotransmitter and peripheral signal mediator serotonin (5-HT). 5-HT receptors are located on the cell membrane of nerve cells and other cell types in animals and mediate the effects of serotonin as the endogenous ligand and of a broad range of pharmaceutical and hallucinogenic drugs. With the exception of the 5-HT3 receptor, a ligand gated ion channel, all other 5-HT receptors are G protein coupled seven transmembrane (or heptahelical) receptors that activate an intracellular second messenger cascade.

5-HT1 receptors are Gi/Go coupled, mediating cellular effects through decreasing cellular levels of cyclic adenosine monophosphate (cAMP).
5-HT2 receptors are Gq/G11 coupled, mediating cellular effects through increasing cellular levels of inositol trisphosphate (IP3) and diacylglycerol (DAG). Three subtypes exist, namely 5-HT2A, 5-HT2B, and 5-HT2C (formerly called 5-HT1C).

The 5-HT3 receptor is a ligand-gated Na+ and K+ cation channel, resulting in a direct plasma membrane depolarization.

The 5-HT4 receptor is Gs coupled, mediating cellular effects through increasing cellular levels of cAMP.

The 5-HT5A receptor is G protein coupled; the primary coupling appears to be through Gi/o, inhibiting adenylate cyclase activity.[7] The 5-HT5B subtype exists, but has not been detected in humans.

The 5-HT7 receptor is Gs coupled, mediating cellular effects through increasing cellular levels of cAMP.

[B][SIZE="4"]Serotonin syndrome[/SIZE][/B]

Extremely high levels of serotonin can have toxic and potentially fatal effects, causing a condition known as serotonin syndrome. In practice, such toxic levels are essentially impossible to reach through an overdose of a single anti-depressant drug, but require a combination of serotonergic agents, such as an SSRI with an MAOI.[9] The intensity of the symptoms of serotonin syndrome vary over a wide spectrum, and the milder forms are seen even at non-toxic levels.[10] For example, recreational doses of MDMA (ecstasy) will generally cause such symptoms but only rarely lead to true toxicity.

[url]http://en.wikipedia.org/wiki/Serotonin[/url]

N2o
 

Salaam,
@ Laila Marium

Thanks. Good site.

@ Miss Naqvi

[QUOTE]Extremely high levels of serotonin can have toxic and potentially fatal effects, causing a condition known as serotonin syndrome.[/QUOTE]

Well, if such conditions do exist, then "Laughinng Gas" (N2O) is generally characterized as an inhibitor of serotonin receptors. So if the patient is really running a high level of serotonin, it is a good idea to inhibit the receptors just in order to disprove the induction of too much serotonin in the 5-ht receptors. For that, N2O is really fast acting and effective.

Under room conditions, it is a colorless non-flammable gas, with a pleasant, slightly sweet odor. It is used in surgery and dentistry for its anesthetic and analgesic effects, where it is commonly known as laughing gas due to the euphoric effects of inhaling it. It is also used as a means to enable short periods of extreme high performance in automobile internal combustion engines by introducing extra oxygen into the intake charge which in turn allows a greater amount of fuel to be added and converted into energy and thereby greatly increasing the power produced by the engine. Nitrous oxide is present in the atmosphere where it acts as a powerful greenhouse gas.

Refrences :

[URL="http://en.wikipedia.org/wiki/Nitrous_oxide"]http://en.wikipedia.org/wiki/Nitrous_oxide[/URL]

[URL="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&list_uids=11873047&dopt=Abstract"]http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&list_uids=11873047&dopt=Abstract[/URL]