α-helical CRF (9-41) peptide

α-helical CRF (9-41) peptide

• Handling and Storage of Synthetic Peptides
• Material Safety Data Sheets (MSDS)

H-DLTFHLLREMLEMAKAEQEAEQAALNRLLLEEA-NH2

H-Asp-Leu-Thr-Phe-His-Leu-Leu-Arg-Glu-Met-Leu-Glu-Met-Ala-Lys-Ala-Glu-Gln-Glu-Ala-Glu-Gln-Ala-Ala-Leu-Asn-Arg-Leu-Leu-Leu-Glu-Glu-Ala-NH2

33

95.37%

C₁₆₆H₂₇₄N₄₆O₅₃S₂

3826.34

Synthetic

Powder

α-helical CRF (9-41) is a corticotropin releasing factor receptor (CRF) antagonist with Ki values of 17, 5 and 0.97 nM at human CRF1, rat CRF2α and mouse CRF2β receptors respectively. α-helical CRF (9-41) decreases anxiety like behaviour in the conditioned fear test and reverses the potentiation of startle amplitude produced by administration of CRF in anxiety models. α-helical CRF (9-41) pre-treatment blocks CRF induced food intake inhibition.

Normally, this peptide will be delivered in lyophilized form and should be stored in a freezer at or below -20 °C. For more details, please refer to the manual:Handling and Storage of Synthetic Peptides

• Swerdlow et al (1989) Potentiation of acoustic startle by corticotropin-releasing factor (CRF) and by fear are both reversed by α-helical CRF (9-41). Neuropsychopharmacology 2 285 PMID: 2610824
• Skórzewska et al (2009). The effect of CRF and α-helical CRF(9–41) on rat fear responses and amino acids release in the central nucleus of the amygdala. Neuropharmacology 57(2) 148 PMID: 19477189
• Smedh et al (2019) Pretreatment with a CRF antagonist amplifies feeding inhibition induced by fourth ventricular cocaine- and amphetamine-regulated transcript peptide. BMC Neurosci 20 11 PMID: 30885137

Trifluoroacetic acid (TFA) has a significant impact on peptides due to its role in the peptide synthesis process.

TFA is essential for the protonation of peptides that lack basic amino acids such as Arginine (Arg), Histidine (His), and Lysine (Lys), or ones that have blocked N-termini. As a result, peptides often contain TFA salts in the final product.

TFA residues, when present in custom peptides, can cause unpredictable fluctuations in experimental data. At a nanomolar (nM) level, TFA can influence cell experiments, hindering cell growth at low concentrations (as low as 10 nM) and promoting it at higher doses (0.5–7.0 mM). It can also serve as an allosteric regulator on the GlyR of glycine receptors, thereby increasing receptor activity at lower glycine concentrations.

In an in vivo setting, TFA can trifluoroacetylate amino groups in proteins and phospholipids, inducing potentially unwanted antibody responses. Moreover, TFA can impact structure studies as it affects spectrum absorption.