Urocortin, rat targets corticotropin-releasing factor receptors (CRFR), specifically human CRF1, rat CRF2alpha, and mouse CRF2beta. It exhibits Ki values of 13 nM for human CRF1, 1.5 nM for rat CRF2alpha, and 0.97 nM for mouse CRF2beta. The compound is used for studying CRF receptor signaling and related physiological functions.

In stably transfected Chinese hamster ovary cells, rat urocortin stimulates the production of cyclic AMP (cAMP) with EC50s of 0.15 nM, 0.063 nM, and 0.087 nM for human CRF1, rat CRF2α, and mouse CRF2β, respectively [2].

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Urocortin, rat demonstrates potent in vitro activity as a CRFR agonist. It binds with high affinity to CRF receptors, with Ki values of 13 nM for human CRF1, 1.5 nM for rat CRF2alpha, and 0.97 nM for mouse CRF2beta. The peptide effectively activates CRF receptor-mediated signaling pathways.

In both food-deprived and non-food-deprived rats, rat urocortin (0.01 to 10 μg) decreased food intake; this effect was also seen in mice following an intravenous injection of 1 μg of rat urocortin. Anxiety-inducing behaviors may be induced by rat urocortin [3].

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In vivo, Urocortin, rat is used to study whether CRF receptor type 2 (CRF2) and its high-affinity ligand, urocortin 1 (Ucn1), can mediate sex-specific physiological responses. The peptide has been studied in CRF receptor 2-deficient (Crhr2-/-) and wild-type (WT) mouse models. It is a valuable tool for investigating CRF receptor biology.

In vitro receptor binding assays for Urocortin, rat typically employ membrane preparations from cells expressing human CRF1, rat CRF2alpha, or mouse CRF2beta receptors. Radioligand binding assays using ¹2⁵I-labeled CRF or other appropriate radioligands are performed to determine binding affinity (Ki). Competition binding experiments are conducted with varying concentrations of the peptide.

In vitro cellular assays for Urocortin, rat involve treating cells expressing CRF receptors with varying concentrations of the peptide (typically 0.001-1000 nM range) for various time points. Readouts include measurement of cAMP accumulation (CRF receptors are Gs-coupled), activation of downstream signaling pathways (e.g., CREB phosphorylation), and assessment of receptor internalization.

In vivo animal studies for Urocortin, rat typically involve administration of the peptide via intracerebroventricular (ICV) injection or systemic routes in rodent models. Endpoints include assessment of stress responses, anxiety-related behaviors, food intake, and cardiovascular parameters. CRF receptor 2-deficient (Crhr2-/-) and wild-type mice are commonly used to study receptor-specific effects.

Pharmacokinetic properties of Urocortin, rat are characteristic of peptide therapeutics. As a 40-amino acid peptide (MW ~4707), it is subject to rapid proteolytic degradation in vivo. The compound is typically administered via injection rather than oral routes. PK parameters including half-life, clearance, and bioavailability are determined via immunoassay or LC-MS.

Urocortin, rat is a research-grade peptide for laboratory use only. As with all bioactive peptides, standard safety precautions should be observed during handling. The compound is not intended for human therapeutic use. Comprehensive toxicology data is not publicly available. Proper handling and disposal procedures should be followed.

[1]. Corticotropin-releasing factor receptors 1 and 2 in anxiety and depression. Curr Opin Pharmacol. 2002 Feb;2(1):23-33.

[2]. The neurobiology of urocortin. Regul Pept. 2000 Sep 25;93(1-3):85-92.

[3]. Corticotropin releasing factor receptors and their ligand family. Ann N Y Acad Sci. 1999 Oct 20;885:312-28.

Urocortin, rat (CAS# 171543-83-2) is a neuropeptide and potent endogenous CRFR agonist. It is used in research to study CRF receptor signaling, stress responses, and related physiological functions. The compound is typically stored as a lyophilized powder at -20degC or -80degC, and should be kept away from moisture. Not for human therapeutic use.

C206H338N62O64

4707.26492

4820.509

171543-83-2

Urocortin, rat TFA

137699472

White to off-white solid powder

73

76

163

339

11800

46

[H]/N=C(/NCCC[C@@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@H](C(=O)N)C(C)C)=O)CO)=O)CC(=O)O)=O)CC1=CC=CC=C1)=O)[C@H](CC)C)=O)[C@H](CC)C)=O)CCCN/C(=N/[H])/N)=O)CC(=O)N)=O)CCC(=O)N)=O)CCC(=O)O)=O)C)=O)CCCN/C(=N/[H])/N)=O)CCC(=O)O)=O)CCCN/C(=N/[H])/N)=O)CCC(=O)N)=O)CO)=O)CCC(=O)N)=O)[C@H](O)C)=O)NC([C@@H](NC([C@@H](NC([C@@H](NC([C@@H](NC([C@@H](NC([C@H]([C@H](O)C)NC([C@@H](NC([C@@H](NC([C@@H](NC([C@@H](NC([C@@H](NC([C@H]([C@H](O)C)NC([C@@H](NC([C@@H](NC([C@H]([C@H](CC)C)NC([C@@H](NC([C@@H](NC([C@H]1N(C([C@H]2N(C([C@@H](NC([C@H](CC(=O)O)N)=O)CC(=O)O)=O)CCC2)=O)CCC1)=O)CC(C)C)=O)CO)=O)=O)CC(=O)O)=O)CC(C)C)=O)=O)CC1=CC=CC=C1)=O)CC1N=CNC=1)=O)CC(C)C)=O)CC(C)C)=O)CCCN/C(=N/[H])/N)=O)=O)CC(C)C)=O)CC(C)C)=O)CCC(=O)O)=O)CC(C)C)=O)C)=O)\N

BTOGVDGOXGIAEB-FJAJBMFWSA-N

InChI=1S/C206H338N62O64.C2HF3O2/c1-28-102(20)156(262-192(323)141(92-271)258-182(313)129(78-98(12)13)251-193(324)142-53-42-72-267(142)201(332)143-54-43-73-268(143)200(331)138(88-154(291)292)256-165(296)113(207)84-151(285)286)194(325)255-137(87-153(289)290)187(318)247-131(80-100(16)17)189(320)266-161(109(27)274)199(330)254-133(82-111-46-35-32-36-47-111)183(314)248-134(83-112-89-223-93-229-112)185(316)246-128(77-97(10)11)180(311)244-126(75-95(6)7)178(309)236-118(52-41-71-228-206(221)222)176(307)265-160(108(26)273)198(329)252-130(79-99(14)15)181(312)245-127(76-96(8)9)179(310)240-124(60-66-150(283)284)172(303)243-125(74-94(4)5)177(308)231-106(24)163(294)232-116(50-39-69-226-204(217)218)175(306)264-159(107(25)272)197(328)242-121(57-63-146(210)277)173(304)257-139(90-269)190(321)241-119(55-61-144(208)275)168(299)235-115(49-38-68-225-203(215)216)167(298)239-123(59-65-149(281)282)170(301)234-114(48-37-67-224-202(213)214)166(297)230-105(23)164(295)233-122(58-64-148(279)280)169(300)238-120(56-62-145(209)276)171(302)249-135(85-147(211)278)186(317)237-117(51-40-70-227-205(219)220)174(305)261-158(104(22)30-3)196(327)263-157(103(21)29-2)195(326)253-132(81-110-44-33-31-34-45-110)184(315)250-136(86-152(287)288)188(319)259-140(91-270)191(322)260-155(101(18)19)162(212)293;3-2(4,5)1(6)7/h31-36,44-47,89,93-109,113-143,155-161,269-274H,28-30,37-43,48-88,90-92,207H2,1-27H3,(H2,208,275)(H2,209,276)(H2,210,277)(H2,211,278)(H2,212,293)(H,223,229)(H,230,297)(H,231,308)(H,232,294)(H,233,295)(H,234,301)(H,235,299)(H,236,309)(H,237,317)(H,238,300)(H,239,298)(H,240,310)(H,241,321)(H,242,328)(H,243,303)(H,244,311)(H,245,312)(H,246,316)(H,247,318)(H,248,314)(H,249,302)(H,250,315)(H,251,324)(H,252,329)(H,253,326)(H,254,330)(H,255,325)(H,256,296)(H,257,304)(H,258,313)(H,259,319)(H,260,322)(H,261,305)(H,262,323)(H,263,327)(H,264,306)(H,265,307)(H,266,320)(H,279,280)(H,281,282)(H,283,284)(H,285,286)(H,287,288)(H,289,290)(H,291,292)(H4,213,214,224)(H4,215,216,225)(H4,217,218,226)(H4,219,220,227)(H4,221,222,228);(H,6,7)/t102-,103-,104-,105-,106-,107+,108+,109+,113-,114-,115-,116-,117-,118-,119-,120-,121-,122-,123-,124-,125-,126-,127-,128-,129-,130-,131-,132-,133-,134-,135-,136-,137-,138-,139-,140-,141-,142-,143-,155-,156-,157-,158-,159-,160-,161-;/m0./s1

(4S)-4-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-5-amino-2-[[(2S)-2-[[(2S)-5-amino-2-[[(2S,3R)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S,3R)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S,3R)-2-[[(2S)-2-[[(2S)-2-[[(2S,3S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-1-[(2S)-1-[(2S)-2-[[(2S)-2-amino-3-carboxypropanoyl]amino]-3-carboxypropanoyl]pyrrolidine-2-carbonyl]pyrrolidine-2-carbonyl]amino]-4-methylpentanoyl]amino]-3-hydroxypropanoyl]amino]-3-methylpentanoyl]amino]-3-carboxypropanoyl]amino]-4-methylpentanoyl]amino]-3-hydroxybutanoyl]amino]-3-phenylpropanoyl]amino]-3-(1H-imidazol-5-yl)propanoyl]amino]-4-methylpentanoyl]amino]-4-methylpentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-hydroxybutanoyl]amino]-4-methylpentanoyl]amino]-4-methylpentanoyl]amino]-4-carboxybutanoyl]amino]-4-methylpentanoyl]amino]propanoyl]amino]-5-carbamimidamidopentanoyl]amino]-3-hydroxybutanoyl]amino]-5-oxopentanoyl]amino]-3-hydroxypropanoyl]amino]-5-oxopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-4-carboxybutanoyl]amino]-5-carbamimidamidopentanoyl]amino]propanoyl]amino]-5-[[(2S)-5-amino-1-[[(2S)-4-amino-1-[[(2S)-1-[[(2S,3S)-1-[[(2S,3S)-1-[[(2S)-1-[[(2S)-1-[[(2S)-1-[[(2S)-1-amino-3-methyl-1-oxobutan-2-yl]amino]-3-hydroxy-1-oxopropan-2-yl]amino]-3-carboxy-1-oxopropan-2-yl]amino]-1-oxo-3-phenylpropan-2-yl]amino]-3-methyl-1-oxopentan-2-yl]amino]-3-methyl-1-oxopentan-2-yl]amino]-5-carbamimidamido-1-oxopentan-2-yl]amino]-1,4-dioxobutan-2-yl]amino]-1,5-dioxopentan-2-yl]amino]-5-oxopentanoic acid;2,2,2-trifluoroacetic acid

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture and light.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)