SB-334867 free base

SB-334867 free base is a selective antagonist of orexin-1 receptor [1].

Orexin-A and orexin-B are two peptides isolated from rat hypothalamus. They are involved in some physiological functions such as the control of feeding, energy metabolism and regulation of the sleep-wake cycle.

SB-334867 free base could inhibit the orexin-A and orexin-B induced calcium responses in CHO-OX1 cells with pKB values of 7.27 and 7.23, respectively. SB-334867 was more selective for OX1 receptor over OX2 receptor. It caused 32.7% and 22% inhibition of orexin-A and orexin-B induced calcium responses in CHO-OX2 cells, respectively. Moreover, SB-334867 was found to reduce both orexin-A-induced and fasting-induced food intake. The acute anorectic effect of it was associated with significant reductions in all active behaviours [1, 2].

References:
[1] Smart D, Sabido-David C, Brough S J, et al.  SB-334867-A: the first selective orexin-1 receptor antagonist. British journal of pharmacology, 2001, 132(6): 1179-1182.
[2] Rodgers R J, Halford J C G, Nunes de Souza R L, et al.  SB-334867, a selective orexin-1 receptor antagonist, enhances behavioural satiety and blocks the hyperphagic effect of orexin-A in rats. European Journal of Neuroscience, 2001, 13(7): 1444-1452.

Evidence that orexin-A-evoked grooming in the rat is mediated by orexin-1 (OX1) receptors, with downstream 5-HT2C receptor involvement.[Pubmed:11205420]

Psychopharmacology (Berl). 2001 Jan 1;153(2):203-9.

RATIONALE: Orexins A and B have recently been discovered and shown to be derived from preproorexin, primarily expressed in the rat hypothalamus. Orexin-A has been ascribed a number of in vivo functions in the rat after intracerebroventricular (ICV) administration, including hyperphagia, neuroendocrine modulation and, most recently, evidence for a behavioural response characterised by an increase in grooming. OBJECTIVES: Here, we have investigated the orexin-receptor subtypes involved in the grooming response to orexin-A (3 microg, ICV) in the rat. METHODS: Male rats, habituated to clear Perspex behavioural observation boxes, were pretreated with antagonists with mixed selectivity for OX1, OX2, 5-HT2B and 5-HT2C receptor subtypes prior to the administration of orexin-A and the intense grooming response elicited by this peptide assessed. RESULTS: Pretreatment of rats with a mixed OX1/5-HT2B/2C receptor antagonist 1-(4-methylsulfanylphenyl)-3-quinolin-4-ylurea (SB-284422), revealed a significant, but incomplete, blockade of orexin-A-induced grooming. Despite the low potency of orexin-A at 5-HT2B and 5-HT2C receptors in vitro (pKi<5), studies were undertaken to determine whether downstream 5-HT2B or 5-HT2C receptors mediate in the grooming-elicited by orexin-A. Whilst the selective 5-HT2B receptor antagonist, SB-215505 (3 mg/kg, PO, 5-HT2B, pKi=8.58; OX1, pKB < 5.15) failed to effect orexin-A-induced grooming, the selective 5-HT2C receptor antagonist, SB-242084 (1 mg/kg, IP, 5-HT2C, pKi = 8.95; OX1, pKB < 5.1) potently antagonised the grooming response to this peptide. This suggested that the partial blockade of orexin-A-induced grooming obtained with SB-284422 might be attributable to its 5-HT2C and/or OX1 receptor blocking activity. However, complete blockade of orexin-A-induced grooming by the subsequently identified selective OX1 receptor antagonist 1-(2-methylbenzoxazol-6-yl)-3-[1,5]naphthyridin-4-yl urea hydrochloride, SB-334867-A (OX1, pKB = 7.4; OX2, pKB = 5.7), devoid of appreciable affinity for either 5-HT2B (pKi < 5.3) or 5-HT2C (pKi < 5.4) receptors, provides the first definitive evidence that a central behavioural effect of orexin-A (grooming) is mediated by OX1 receptors. CONCLUSIONS: This data suggests that orexin-A indirectly activates 5-HT2C receptors downstream from OX1 receptors to elicit grooming in the rat. The use of SB-334867-A in vivo will enable the role of OX,1 receptors within the rat central nervous system to be further characterised.

1,3-Biarylureas as selective non-peptide antagonists of the orexin-1 receptor.[Pubmed:11459658]

Bioorg Med Chem Lett. 2001 Jul 23;11(14):1907-10.

This communication reports SARs for the first orexin-1 receptor antagonist series of 1-aryl-3-quinolin-4-yl and 1-aryl-3-naphthyridin-4-yl ureas. One of these compounds, 31 (SB-334867), has excellent selectivity for the orexin-1 receptor, blood-brain barrier permeability and shows in vivo activity following ip dosing.

SB-334867-A: the first selective orexin-1 receptor antagonist.[Pubmed:11250867]

Br J Pharmacol. 2001 Mar;132(6):1179-82.

The pharmacology of various peptide and non-peptide ligands was studied in Chinese hamster ovary (CHO) cells stably expressing human orexin-1 (OX(1)) or orexin-2 (OX(2)) receptors by measuring intracellular calcium ([Ca(2+)](i)) using Fluo-3AM. Orexin-A and orexin-B increased [Ca(2+)](i) in CHO-OX(1) (pEC(50)=8.38+/-0.04 and 7.26+/-0.05 respectively, n=12) and CHO-OX(2) (pEC(50)=8.20+/-0.03 and 8.26+/-0.04 respectively, n=8) cells. However, neuropeptide Y and secretin (10 pM - 10 microM) displayed neither agonist nor antagonist properties in either cell-line. SB-334867-A (1-(2-Methyylbenzoxanzol-6-yl)-3-[1,5]naphthyridin-4-yl-urea hydrochloride) inhibited the orexin-A (10 nM) and orexin-B (100 nM)-induced calcium responses (pK(B)=7.27+/-0.04 and 7.23+/-0.03 respectively, n=8), but had no effect on the UTP (3 microM)-induced calcium response in CHO-OX(1) cells. SB-334867-A (10 microM) also inhibited OX(2) mediated calcium responses (32.7+/-1.9% versus orexin-A). SB-334867-A was devoid of agonist properties in either cell-line. In conclusion, SB-334867-A is a non-peptide OX(1) selective receptor antagonist.

A selective orexin-1 receptor antagonist reduces food consumption in male and female rats.[Pubmed:11102651]

Regul Pept. 2000 Dec 22;96(1-2):45-51.

A variety of evidence implicates the orexins, especially orexin-A, in the regulation of food intake, but it has not been established whether this effect is mediated by the orexin-1 or orexin-2 receptor. In the present study, a selective orexin-1 receptor antagonist, 1-(2-methylbenzoxazol-6-yl)-3-[1,5]naphthyridin-4-yl urea hydrochloride (SB-334867-A), was administered intraperitoneally to rats under various conditions, and food consumption was subsequently measured over 24 h. In male rats, a single dose of SB-334867-A (30 mg/kg, i.p.) given during the light phase reduced both orexin-A-induced food intake (7 nmol, i.c.v.) and feeding stimulated by an overnight fast for 4 h. When given at the start of the dark phase, food consumption was reduced in both male and female rats over 24 h. Daily injections at the start of the dark phase for 3 days reduced natural feeding in male rats over 24 h on days one and three. These findings demonstrate direct inhibition of orexin-A induced food intake with a selective orexin-1 receptor antagonist. Furthermore, the suppression of nocturnal feeding and food intake stimulated by an overnight fast supports other evidence that orexin-A is involved in the regulation of natural feeding and suggests that orexin-1 receptor antagonists could be useful in the treatment of obesity.

SB-334867 free base (SB334867A free base) is an excellent, selective and blood–brain barrier permeable orexin-1 (OX1) receptor antagonist, shows selectivity over OX2 (pKb=7.4), 100-fold over 5-HT2B, 5-HT2C with pKi values of 5.4 and 5.3, respectively. SB-334867 reduces ethanol consumption and inhibits the acquisition of morphine-induced sensitization to locomotor activity in vivo.

SB-334867 free base,792173-99-0,SB334867A free base,Natural Products,OX Receptor, buy SB-334867 free base , SB-334867 free base supplier , purchase SB-334867 free base , SB-334867 free base cost , SB-334867 free base manufacturer , order SB-334867 free base , high purity SB-334867 free base