Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Orexin shopping experience:

1. Compare - without doubt the biggest advantage that the Orexin offers shoppers today is the ability to compare thousands of Orexin at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.

2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about

3. Testimonials - don't know anybody that has bought a Orexin? Wrong! If the Orexin is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.

4. Questions - Got a question about Orexin then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....

5. Reputation - Never heard of the company selling Orexin? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Orexin and build up a picture of their reputation for sales, returns, customer service, delivery etc.

6. Returns - still worried that even after all of the above your Orexin wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.

7. Feedback - happy with your Orexin then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.

8. Security - check for the yellow padlock on the Orexin site before you buy, and the s after http:/ /i.e. https:// = a secure site

9. Contact - got a question about Orexin, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.

10. Payment - ready to pay for your Orexin, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.

{{protein|Name=hypocretin (orexin) neuropeptide precursor|caption=|image=|width=|HGNCid=4847|Symbol=HCRT|AltSymbols=|EntrezGene=3060|OMIM=602358|RefSeq=NM_001524|UniProt=O43612|PDB=|ECnumber=|Chromosome=17|Arm=q|Band=21|LocusSupplementaryData=-->Orexins, also called hypocretins, are the common names given to a pair of highly excitatory neuropeptide hormones that were simultaneously discovered by two groups of researchers in rat brains.

The two related peptides (orexin A and B, or hypocretin-1 and -2), with approximately 50% sequence identity, are produced by cleavage of a single precursor protein. Studies suggest that orexin A/hypocretin-1 may be of greater biological importance than orexin B/hypocretin-2. Although these peptides are produced by a very small population of cells in the lateral and posterior hypothalamus, they send projections throughout the brain. The orexin peptides bind to the orexin receptor, a G-protein coupled receptor.

The orexins/hypocretins are strongly conserved peptides, found in all major classes of vertebrates. The peptides are thought to have arisen early in vertebrate evolution.

Functions The orexin/hypocretin system was initially suggested to be primarily involved in the stimulation of food intake, based on the finding that central administration of orexin A/hypocretin-1 increases food intake. The discovery that orexin/hypocretin dysregulation causes the sleep disorder narcolepsy full text subsequently indicated a major role for this system in sleep regulation. Narcolepsy results in excessive daytime sleepiness, inability to consolidate wakefulness in the day (and sleep at night), and cataplexy (loss of muscle tone in response to strong, usually positive, emotions). Dogs that lack a functional receptor for orexin/hypocretin have narcolepsy, while animals and people lacking the orexin/hypocretin neuropeptide itself also have narcolepsy. Orexin/hypocretin neurons strongly excite various brain nuclei with important roles in wakefulness including the dopamine, norepinephrine, histamine and acetylcholine systems and appear to play an important role in stabilizing wakefulness and sleep.

Recent studies indicate that a major role of the orexin/hypocretin system is to integrate metabolic, circadian and sleep debt influences to determine whether the animal should be asleep or awake and active. Central administration of orexin A/hypocretin-1 strongly promotes wakefulness, increases body temperature, locomotion and elicits a strong increase in energy expenditure. Sleep deprivation also increases orexin A/hypocretin-1 transmission. The orexin/hypocretin system may thus be more important in the regulation of energy expenditure than food intake. In fact, orexin/hypocretin-deficient narcoleptic patients have increased obesity rather than decreased Body mass index, as would be expected if orexin/hypocretin were primarily an appetite stimulating peptide.

Leptin is a hormone produced by fat cells and acts as a long-term internal measure of energy state. Ghrelin is a short term factor secreted by the stomach just before an expected meal, and strongly promotes food intake.

Orexin-producing cells have recently been shown to be inhibited by glucose but are activated by ghrelin.

Hypocretin-producing cells have recently been shown to be inhibited by leptin (by leptin receptors) but are activated by ghrelin and hypoglycemia. Orexin/hypocretin (as of 2007) is therefore a very important link between metabolism and sleep regulation. Such a relationship has been long suspected based on the observation that long-term sleep deprivation in rodents dramatically increases food intake and energy metabolism, i.e. catabolism, with lethal consequences on a long term basis.

The research on orexin/hypocretin is still in an early phase, although many scientists believe that orexin/hypocretin-based drugs could help narcolepsy and increase alertness in the brain without the side effects of amfetamine.

Preliminary research has been conducted that shows potential for orexin blockers in the treatment of alcoholism. Brown rats given drugs which targeted the orexin system lost interest in alcohol despite being given free access in experiments.

History and nomenclature Masashi Yanagisawa and colleagues at the University of Texas Southwestern Medical Center at Dallas, coined the term orexin to reflect the orexigenic (appetite-stimulating) activity of these hormones.

Luis DeLecea, Thomas Kilduff, and colleagues also reported discovery of these same peptides, dubbing them hypocretins to indicate that they are synthesized in the hypothalamus and to reflect their similarity to a class of hormones called incretins (i.e., hypothalamic incretin).

The name of this family of peptides is currently in dispute. The name "orexin" has been rejected by some due to evidence that the orexigenic effects of these peptides may be incidental or trivial, while other groups maintain that the name "hypocretin" is awkward, pointing out that many neuropeptides have names that are unrelated to their most important functions. The name "hyporexin" has been suggested as a compromise, but as of yet has not been commonly used. Both "orexin" and "hypocretin" will likely continue to appear in published works until a preferred name has been accepted by the scientific community.

Drugs SB649868 is under development by GlaxoSmithKline for sleep disorders; it is an orexin receptor antagonist. ACT-078573 is a similar compound under development by Actelion.

References

External links

{{protein|Name=hypocretin (orexin) neuropeptide precursor|caption=|image=|width=|HGNCid=4847|Symbol=HCRT|AltSymbols=|EntrezGene=3060|OMIM=602358|RefSeq=NM_001524|UniProt=O43612|PDB=|ECnumber=|Chromosome=17|Arm=q|Band=21|LocusSupplementaryData=-->Orexins, also called hypocretins, are the common names given to a pair of highly excitatory neuropeptide hormones that were simultaneously discovered by two groups of researchers in rat brains.

The two related peptides (orexin A and B, or hypocretin-1 and -2), with approximately 50% sequence identity, are produced by cleavage of a single precursor protein. Studies suggest that orexin A/hypocretin-1 may be of greater biological importance than orexin B/hypocretin-2. Although these peptides are produced by a very small population of cells in the lateral and posterior hypothalamus, they send projections throughout the brain. The orexin peptides bind to the orexin receptor, a G-protein coupled receptor.

The orexins/hypocretins are strongly conserved peptides, found in all major classes of vertebrates. The peptides are thought to have arisen early in vertebrate evolution.

Functions The orexin/hypocretin system was initially suggested to be primarily involved in the stimulation of food intake, based on the finding that central administration of orexin A/hypocretin-1 increases food intake. The discovery that orexin/hypocretin dysregulation causes the sleep disorder narcolepsy full text subsequently indicated a major role for this system in sleep regulation. Narcolepsy results in excessive daytime sleepiness, inability to consolidate wakefulness in the day (and sleep at night), and cataplexy (loss of muscle tone in response to strong, usually positive, emotions). Dogs that lack a functional receptor for orexin/hypocretin have narcolepsy, while animals and people lacking the orexin/hypocretin neuropeptide itself also have narcolepsy. Orexin/hypocretin neurons strongly excite various brain nuclei with important roles in wakefulness including the dopamine, norepinephrine, histamine and acetylcholine systems and appear to play an important role in stabilizing wakefulness and sleep.

Recent studies indicate that a major role of the orexin/hypocretin system is to integrate metabolic, circadian and sleep debt influences to determine whether the animal should be asleep or awake and active. Central administration of orexin A/hypocretin-1 strongly promotes wakefulness, increases body temperature, locomotion and elicits a strong increase in energy expenditure. Sleep deprivation also increases orexin A/hypocretin-1 transmission. The orexin/hypocretin system may thus be more important in the regulation of energy expenditure than food intake. In fact, orexin/hypocretin-deficient narcoleptic patients have increased obesity rather than decreased Body mass index, as would be expected if orexin/hypocretin were primarily an appetite stimulating peptide.

Leptin is a hormone produced by fat cells and acts as a long-term internal measure of energy state. Ghrelin is a short term factor secreted by the stomach just before an expected meal, and strongly promotes food intake.

Orexin-producing cells have recently been shown to be inhibited by glucose but are activated by ghrelin.

Hypocretin-producing cells have recently been shown to be inhibited by leptin (by leptin receptors) but are activated by ghrelin and hypoglycemia. Orexin/hypocretin (as of 2007) is therefore a very important link between metabolism and sleep regulation. Such a relationship has been long suspected based on the observation that long-term sleep deprivation in rodents dramatically increases food intake and energy metabolism, i.e. catabolism, with lethal consequences on a long term basis.

The research on orexin/hypocretin is still in an early phase, although many scientists believe that orexin/hypocretin-based drugs could help narcolepsy and increase alertness in the brain without the side effects of amfetamine.

Preliminary research has been conducted that shows potential for orexin blockers in the treatment of alcoholism. Brown rats given drugs which targeted the orexin system lost interest in alcohol despite being given free access in experiments.

History and nomenclature Masashi Yanagisawa and colleagues at the University of Texas Southwestern Medical Center at Dallas, coined the term orexin to reflect the orexigenic (appetite-stimulating) activity of these hormones.

Luis DeLecea, Thomas Kilduff, and colleagues also reported discovery of these same peptides, dubbing them hypocretins to indicate that they are synthesized in the hypothalamus and to reflect their similarity to a class of hormones called incretins (i.e., hypothalamic incretin).

The name of this family of peptides is currently in dispute. The name "orexin" has been rejected by some due to evidence that the orexigenic effects of these peptides may be incidental or trivial, while other groups maintain that the name "hypocretin" is awkward, pointing out that many neuropeptides have names that are unrelated to their most important functions. The name "hyporexin" has been suggested as a compromise, but as of yet has not been commonly used. Both "orexin" and "hypocretin" will likely continue to appear in published works until a preferred name has been accepted by the scientific community.

Drugs SB649868 is under development by GlaxoSmithKline for sleep disorders; it is an orexin receptor antagonist. ACT-078573 is a similar compound under development by Actelion.

References

External links

Orexin - Wikipedia, the free encyclopedia
Orexins, also called hypocretins, are the common names given to a pair of highly excitatory neuropeptide hormones that were simultaneously discovered by two groups of researchers ...

Orexin receptor - Wikipedia, the free encyclopedia
The orexin receptor (also referred to as the hypocretin receptor) is a G-protein-coupled receptor that binds the neuropeptide hormone orexin. There are two variants each encoded by ...

BBC - Science & Nature - Horizon - Living Nightmare
Documentary featuring new research about narcolespy, including information about orexin--a chemical that appears to help humans wake up.

Orexin A
Systemic and Nasal Delivery of Orexin-A (Hypocretin-1) Reduces the Effects of Sleep Deprivation on Cognitive Performance in Nonhuman Primates

Modafinil (Provigil, Alertec), narcolepsy-catalepsy and hypothalamic ...
Modafinil more effectively induces wakefulness in orexin-null mice than in wild-type littermates by Willie JT, Renthal W, Chemelli RM, Miller MS,

Pfam: Family: Orexin (PF02072)
Interpro entry IPR001704. Orexins (also known as hypocretins) are recently identified neuropeptides that are specifically localised to the hypothalamus.

Pfam: Family: Orexin_rec2 (PF03827)
Interpro entry IPR004060. G-protein-coupled receptors, GPCRs, constitute a vast protein family that encompasses a wide range of functions (including various autocrine ...

BBC NEWS | Health | Chemical may stop alcohol craving
A team from Melbourne's Howard Florey Institute discovered blocking the action of the brain's orexin system can also prevent someone relapsing.

Why we need a siesta after dinner - 05 June 2006 - New Scientist
Burdakov’s team studied a group of brain cells called orexin neurons, which are found in the hypothalamus and produce proteins called orexins that are essential for maintaining ...

STRUCTURE OF OREXIN
Slide 4 of 13