Skip to Content
Merck
All Photos(1)

Key Documents

O6012

Sigma-Aldrich

Orexin A human, rat, mouse

≥97% (HPLC)

Synonym(s):

Hypocretin 1

Sign Into View Organizational & Contract Pricing


About This Item

Empirical Formula (Hill Notation):
C152H243N47O44S4
CAS Number:
Molecular Weight:
3561.10
MDL number:
UNSPSC Code:
51111800
NACRES:
NA.32

sterility

non-sterile

Quality Level

Assay

≥97% (HPLC)

form

powder

solubility

1% acetic acid: 1.00-1.04 mg/mL, clear, colorless
water: 1.00-1.04 mg/mL, clear, colorless

UniProt accession no.

shipped in

ambient

storage temp.

−20°C

InChI

1S/C152H243N47O44S4/c1-20-76(14)118(146(239)188-96(51-74(10)11)138(231)197-119(80(18)201)147(240)180-92(121(156)214)47-70(2)3)195-115(209)62-166-123(216)78(16)171-124(217)79(17)172-131(224)99(55-84-59-162-69-169-84)186-136(229)100(56-111(155)205)174-114(208)61-165-122(215)77(15)170-113(207)60-167-125(218)98(54-83-58-161-68-168-83)185-134(227)95(50-73(8)9)183-132(225)93(48-71(4)5)182-129(222)90(38-41-116(210)211)179-135(228)97(53-82-32-34-85(203)35-33-82)184-133(226)94(49-72(6)7)181-127(220)88(29-24-44-164-152(159)160)177-140(233)104-64-244-245-65-105-141(234)176-87(28-23-43-163-151(157)158)126(219)178-89(36-39-110(154)204)128(221)175-86(27-21-22-42-153)130(223)196-120(81(19)202)148(241)194-107(142(235)190-103(63-200)139(232)192-104)67-247-246-66-106(143(236)193-105)191-137(230)101(57-117(212)213)187-144(237)108-30-26-46-199(108)150(243)102(52-75(12)13)189-145(238)109-31-25-45-198(109)149(242)91-37-40-112(206)173-91/h32-35,58-59,68-81,86-109,118-120,200-203H,20-31,36-57,60-67,153H2,1-19H3,(H2,154,204)(H2,155,205)(H2,156,214)(H,161,168)(H,162,169)(H,165,215)(H,166,216)(H,167,218)(H,170,207)(H,171,217)(H,172,224)(H,173,206)(H,174,208)(H,175,221)(H,176,234)(H,177,233)(H,178,219)(H,179,228)(H,180,240)(H,181,220)(H,182,222)(H,183,225)(H,184,226)(H,185,227)(H,186,229)(H,187,237)(H,188,239)(H,189,238)(H,190,235)(H,191,230)(H,192,232)(H,193,236)(H,194,241)(H,195,209)(H,196,223)(H,197,231)(H,210,211)(H,212,213)(H4,157,158,163)(H4,159,160,164)/t76-,77-,78-,79-,80+,81+,86-,87-,88-,89-,90-,91-,92-,93-,94-,95-,96-,97-,98-,99-,100-,101-,102-,103-,104-,105-,106-,107-,108-,109-,118-,119-,120-/m0/s1

InChI key

OFNHNCAUVYOTPM-IIIOAANCSA-N

Gene Information

human ... HCRT(3060)
mouse ... Hcrt(15171)
rat ... Hcrt(25723)

Amino Acid Sequence

Glp-Pro-Leu-Pro-Asp-Cys-Cys-Arg-Gln-Lys-Thr-Cys-Ser-Cys-Arg-Leu-Tyr-Glu-Leu-Leu-His-Gly-Ala-Gly-Asn-His-Ala-Ala-Gly-Ile-Leu-Thr-Leu-NH2 [Disulfide Bridges: 6-12; 7-14]

General description

Orexin A is characterized with an N-terminal pyroglutamyl residue, two intramolecular disulfide bridges and a C-terminal amidation.
Orexin A, also known as hypocretin 1 (hcrt1), is a 33 amino acid excitatory neuropeptide, localized in a small set of neurons in the perifornical area of the hypothalamus. It is synthesized from the precursor protein prepro-orexin in neurons. Orexin A binds to its G-protein-coupled receptor orexin-1 (OX1) which is also called as hcrt receptors 1 (hcrtr1).

Application

Orexin A has been used to study its effect on serum luteinizing hormone (LH) concentration in lateral ventricle in ovariectomized (OVX) gilts and is used to study the behavioral and metabolic effects of central injections of orexin A on pigeons (Columba livia).
Orexin A human, rat, mouse has been used to study its effect on the functioning of porcine pancreatic islets. It has also been used as an orexin receptor 1 (OX1R) antagonist to study the effect of orexin systems in the effect of etonogestrel on respiratory response to prolonged metabolic acidosis.

Biochem/physiol Actions

Orexins (hypocretins) comprise a family of hypothalamic peptides that are involved in the initiation of sleep and in feeding behavior. Orexin A stimulates food intake through activation of the OX1 receptor. Orexin B activates OX2 receptors. Both OX1 and OX2 receptors are involved in maintaining arousal. OX2 receptors appear to be inhibitory autoreceptors on orexin-containing neurons.
Orexins plays a vital role in several physiological functions including feeding, neuroendocrine regulation and arousal. In addition to this, it is also associated with the pathophysiology of narcolepsy. Orexin A, expressed in locus coeruleus (LC) area, binds to orexin-1 (OX1) receptor and regulates rapid eye movement (REM) sleep by acting on the firing rate of noradrenergic neurons. Orexin A release is regulated by suprachiasmatic nucleus (SCN).

Other Notes

Lyophilized from 0.1% TFA in H2O

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

Already Own This Product?

Find documentation for the products that you have recently purchased in the Document Library.

Visit the Document Library

Customers Also Viewed

Eric Y Wang et al.
Nature, 595(7866), 283-288 (2021-05-20)
COVID-19 manifests with a wide spectrum of clinical phenotypes that are characterized by exaggerated and misdirected host immune responses1-6. Although pathological innate immune activation is well-documented in severe disease1, the effect of autoantibodies on disease progression is less well-defined. Here
Orexin and central regulation of cardiorespiratory system
Vitamins & Hormones, 89, 159-184 (2012)
Lesions of the suprachiasmatic nucleus eliminate the daily rhythm of hypocretin-1 release.
Zhang S
Sleep, 27(4), 619-627 (2004)
Tao Li et al.
Journal of neuroinflammation, 17(1), 187-187 (2020-06-17)
Orexins are two neuropeptides (orexin A, OXA; orexin B, OXB) secreted mainly from the lateral hypothalamus, which exert a wide range of physiological effects by activating two types of receptors (orexin receptor 1, OXR1; orexin receptor 2, OXR2). OXA has
Orexin A modulates endocrine function and viability of porcine pancreatic islets
Sassek M, et al.
Journal of Physiology And Pharmacology, 68, 815-821 (2017)

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service