Binding studies

SK-N-MC cell membranes (25 μg) were incubated in 1 mL of binding buffer [10 mM HEPES, pH 7.4, 5 mM MgCl2 and 0.2% bovine serum albumin (BSA)] containing 10 pM 125I-CGRP and inhibitor. After incubation at room temperature for 3 hrs, the assay was terminated by filtration through GFB glass fibre filter plates that had been blocked with 0.5% polyethyleneimine for 3 hrs. The filters were washed three times with ice-cold assay buffer, and then the plates were air dried. Scintillation fluid (50 mL) was added and the radioactivity was counted on a Topcount. Non-specific binding was determined by using a final concentration of 500 pM Olcegepant. Data analysis was carried out by using Prism and the Ki was determined by using the Cheng–Prusoff equation.

Cell lines

SK-N-MC cells

Preparation method

The solubility of this compound in DMSO is >10 mM. General tips for obtaining a higher concentration: Please warm the tube at 37℃ for 10 minutes and/or shake it in the ultrasonic bath for a while. Stock solution can be stored below -20℃ for several months.

Reacting condition

10 mins

Applications

In SK-N-MC cells, CGRP-induced cAMP production was antagonised by both CGRP-(8-37) and Olcegepant with pA2 values of 7.8 and 11.2, respectively.

Animal models

Rats

Dosage form

900 μg/kg; i.v.; 10 mins

Applications

Pre-treatment with Olcegepant (900 μg/kg) inhibited the capsaicin-induced expression of Fos (57%) throughout the spinal trigeminal nucleus, but did not change the expression of phosphorylated extracellular signal-regulated kinase in the trigeminal ganglion.

Other notes

Please test the solubility of all compounds indoor, and the actual solubility may slightly differ with the theoretical value. This is caused by an experimental system error and it is normal.

Olcegepant Description:IC50: 0.1nM on human brain vessels [1]
Olcegepant is the first potent and selective non-peptide antagonist of the calcitonin gene-related peptide 1 (CGRP1) receptor, a key modulator in neurogenic inflammatory pain. Under development by Boehringer Ingelheim GmbH, olcegepant is an intravenously formulated treatment for acute attacks of migraine.
In vitro: Functional studies with SK-N-MC cells demonstrated that CGRP-induced cAMP production was antagonised by both CGRP- (8-37) and olcegepant with pA2 values of 7.8 and 11.2, respectively. [1].
In vivo: Pre-treatment with olcegepant (900 mg/kg) inhibited the capsaicin-induced expression of Fos throughout the spinal trigeminal nucleus by 57%. In contrast, the expression of phosphorylated extracellular signal-regulated kinase in the trigeminal ganglion was not changed by olcegepant pre-treatment. CGRP receptor inhibition, which has been shown to decrease spinal trigeminal activity, is likely to occur in the central nervous system rather than in the periphery including the trigeminal ganglion. This may be important for future therapeutic interventions with CGRP receptor antagonists in migraine. [2].
Clinical trial: In a phase II clinical trial, olcegepant reduced the severity of headache in 60% of migraine sufferers and met secondary endpoints including headache-free rate and rate of sustained response. Only mild-to-moderate transient adverse events were observed, with no adverse cardiovascular symptoms reported. The compound appears to be an effective anti-migraine medication that is well tolerated and does not display the vasoconstrictive effect that precludes the use of triptans and dihydroergotamine in certain patients [3].
Reference:
[1] Edvinsson L, Alm R, Shaw D, Rutledge RZ, Koblan KS, Longmore J, Kane SA. Effect of the CGRP receptor antagonist BIBN4096BS in human cerebral, coronary and omental arteries and in SK-N-MC cells. Eur J Pharmacol. 2002;434(1-2):49-53.
[2] Sixt ML, Messlinger K, Fischer MJ. Calcitonin gene-related peptide receptor antagonist olcegepant acts in the spinal trigeminal nucleus. Brain. 2009;132(Pt 11):3134-41.
[3] Recober A, Russo AF. Olcegepant, a non-peptide CGRP1 antagonist for migraine treatment. IDrugs. 2007;10(8):566-74.