Urotensin I (Catostomus urotensin I) TFA, a CRF-like neuropeptide, acts as an agonist ofCRF receptorwithpEC₅₀s of 11.46, 9.36 and 9.85 for human CRF₁, human CRF₂and rat CRF_2αreceptors in CHO cells, andK_is of 0.4, 1.8, and 5.7 nM for hCRF₁, rCRF_2αand mCRF_2βreceptors, respectively^[1][2].

pEC50: 11.46 (human CRF₁, CHO cells), 9.36 (human CRF₂, CHO cells), 9.85 (rat CRF_2α, CHO cells)^[1]
Ki: 0.4 nM (hCRF₁, cell assay), 1.8 nM (rCRF_2α, cell assay), and 5.7 nM (mCRF_2β, cell assay)^[2]

Urotensin I is 2-3 times more potent than CRF or sauvagine in stimulating ACTH release from a superfused goldfish anterior pituitary cell column^[3].
Rat tail artery strips were incubated in the presence of 4 x 10(-3) M theophylline and Urotensin I (UI). At the concentrations of 1.50, 7.50 mU/ml but not of 0.75 mU/ml Urotensin I, the content of cAMP increased significantly^[4].

Intraperitoneal injections of urotensin I, a CRF-like neuropeptide isolated from the caudal neurosecretory system of the teleost Catostomus commersoni, ovine CRF and sauvagine all produced significant increases in circulating levels of plasma cortisol in goldfish in which endogenous ACTH secretion was suppressed with betamethasone^[3].

4983.48

Solid

C₂₁₂H₃₄₁F₃N₆₂O₆₉S₂

Asn-Asp-Asp-Pro-Pro-Ile-Ser-Ile-Asp-Leu-Thr-Phe-His-Leu-Leu-Arg-Asn-Met-Ile-Glu-Met-Ala-Arg-Ile-Glu-Asn-Glu-Arg-Glu-Gln-Ala-Gly-Leu-Asn-Arg-Lys-Tyr-Leu-Asp-Glu-Val-NH2

NDDPPISIDLTFHLLRNMIEMARIENEREQAGLNRKYLDEV-NH2

Room temperature in continental US; may vary elsewhere.

Sealed storage, away from moisture

*In solvent : -80°C, 6 months; -20°C, 1 month (sealed storage, away from moisture)