bovine A2a ( Ki = 2.0 nM ); rat A2a ( Ki = 2.3 nM )

SCH58261 (0.01 mg/kg, i.p.) decreases demyelination and levels of TNF-α, Fas-L, PAR, Bax expression, and JNK MAPK activation in mice with spinal cord injury. The neurological deficit is improved with long-term SCH58261 administration.[2] SCH58261 (2 mg/kg, i.p.) ameliorates the motor disturbance and 6-OHDA-induced bradykinesia in rats with Parkinson's disease.[3]

Male Sprague-Dawley rats weighing 250–300 g are used to harvest the cortex and striatum of the rat brain. Within 10 mm after an animal is sacrificed, the frontal cortex and striatum of cow brains are taken from a nearby abattoir. [3H]CHA and [3H]CGS 21680 are used in the A1 and A2a ADO receptor binding assays. (3H) 2-[4-phenethylamino]-(2-carboxyethyl) as radioligands, 5'-N-ethylcarboxamidoadenosinel in this case. Using [125I]AB-MECA as the radioligand, a binding assay is carried out on CHO cells that have been stable transfected with the rat brain A3 ADO receptor. Saturation experiments are performed on rat brain tissues in the absence or presence of varying concentrations of SCH 58261 (7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]) in order to ascertain the type of inhibition (competitive or noncompetitive) at A1 ADO ([3H]CHA, 0.125-64 nM) and A2a ADO receptors ([3HJCGS 21680, 1-128 aM).[1,5-c]triazolo[1,2,4-]pyrimidine}. SCH 58261's affinity for a number of neurotransmitter binding sites, including mu-opioid, benzodiazepine, N-methyl-D-aspartate, D1 and D2 dopamine receptors, 5-HT1 and 5-HT2 receptors, M1 and M2 muscarinic receptors, and alpha-1, alpha-2, and beta-1 adrenoceptors, is determined using standard procedures.

The PC12 cells were randomly divided into 8 groups: A2a agonist group (CGS21680), A2a antagonist group (SCH58261), PKC inhibitor group (Chelerythrine, CHE), solvent control group (DMSO), intermittent hypoxia group (IH), persistent hypoxic group (SH), air-simulated control group (AC), and normal control group (Control). Cells for A2a agonist group, A2a antagonist group, PKC inhibitor group, solvent control group and intermittent hypoxia group (IH) were placed in hypoxic cell culture chambers. PC12 cells were seeded to a 96-well plate at a density of 5000/well and placed at 37 °C in a 5% CO₂ cell incubator for 24 h.
After attachment, cells were placed in an IH chamber which was controlled by regulating the ration of gaseous mixture that mimicked different levels of hypoxia exposure. The A2a receptor agonist CGS21680 (100 u M), the A2a receptor antagonist SCH58261(200 u M), and the PKC antagonist CHE(200 u M) were dissolved in 0.1% DMSO solution in different concentrations. These various treated-cells were incubated in IH chamber and exposed to 9 h-deoxygenation-reoxygenation cycle of 5% oxygen for 60 min. and 20% oxygen for 30 min.. For sustained hypoxia (SH), this group was treated with 5% oxygen for 6 h. Some cells were placed in a normal incubator at the exposure level of 5% CO2 for 9 h as the control group. In the room air (AC) group, cells were treated with room air for 9 h to assess the effect of frequent replacement of the gas on cells. The PC12 cells model was identified by the morphological changes using microscope as well as MTT assay which is an indicator of cellular viability. Cells were treated with 0.5 mg/ml of MTT solution for 2 h, and then solubilized in dimethyl sulfoxide. Optical density was measured by a spectrophotometer at a wavelength of 570 nm.[5]

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In the NSCLC cell line H1975, SCH 58261 reduces cell viability in a concentration-dependent manner.

SCH58261, systemically administered (0.01 mg/kg intraperitoneal. 1, 6 and 10 hours after SCI), reduced demyelination and levels of TNF-α, Fas-L, PAR, Bax expression and activation of JNK mitogen-activated protein kinase (MAPK) 24 hours after SCI. Chronic SCH58261 administration, by mini-osmotic pump delivery for 10 days, improved the neurological deficit up to 10 days after SCI. Adenosine A2A receptors are physiologically expressed in the spinal cord by astrocytes, microglia and oligodendrocytes. Soon after SCI (24 hours), these receptors showed enhanced expression in neurons. Both the A2A agonist and antagonist, administered intraperitoneally, reduced expression of the A2A receptor, ruling out the possibility that the neuroprotective effects of the A2A agonist are due to A2A receptor desensitization. When the A2A antagonist and agonist were centrally injected into injured SC, only SCH58261 appeared neuroprotective, while CGS21680 was ineffective.[2]

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In order to induce experimental model of Parkinson's disease, 6-hydoxydopamine (8 μg/rat) was injected unilaterally into the SNc. After three weeks as a recovery period, 6-OHDA-induced bradykinesia and balance disturbances were assessed by using beam traversal test 10, 30 and 60 minutes after intraperitoneal injections of the drugs (caffeine, SCH58261).[3]

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Dissolved in Tween 80 (1 %) and administered (0.01 mg/kg, i.p.) twice/day for 7 days.

Rat

[1]. J Pharmacol Exp Ther . 1996 Feb;276(2):398-404.

[2]. AJ Neuroinflammation . 2011 Apr 12:8:31.

[3]. Acta Cir Bras . 2016 Feb;31(2):133-7.

[4]. PPAR Res . 2020 Mar 6:2020:2410264.

[5]. Brain Res Bull. 2019 Aug:150:118-126.

LSM-3822 is a member of triazolopyrimidines.
We have characterized the in vitro pharmacological profile of the new potent and selective A2a adenosine receptor antagonist SCH 58261 [7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]-1,2, 4-triazolo[1,5-c]pyrimidine]. In binding studies on rat and bovine brain tissues, SCH 58261 showed affinity in the low nanomolar range at A2a adenosine striatal receptors and good A2a adenosine vs. A1 adenosine selectivity (about 50- to 100-fold in rat and bovine brain, respectively). SCH 58261 did not show affinity for either the A3 adenosine receptor or other receptors at concentrations up to 1 microM. Saturation experiments on rat A1 and A2a adenosine receptors indicated the competitive nature of the antagonism. SCH 58261 antagonized competitively the effects induced by the A2a adenosine-selective agonist CGS 21680 (2-[4-(2-carboxyethyl)-phenethyl-amino]-5'-N- ethylcarboxamidoadenosine) in two functional assays, such as inhibition of rabbit platelet aggregation and porcine coronary artery relaxation. Specifically, the compound showed pA2 values of 7.9 and 9.5, respectively. SCH 58261 (300 nM) failed to antagonize 5'-N-ethylcarboxamidoadenosine-induced vasorelaxation in the isolated guinea pig aorta, a response mediated by A2b adenosine receptors. Likewise, at the same concentration, the compound weakly inhibited the A1 adenosine-mediated negative chronotropic effect induced by 2-chloro-N6-cyclopentyladenosine in the isolated rat atria. These data show that SCH 58261 is a potent and selective non-xanthine A2a adenosine antagonist which has competitive properties in biological responses mediated by this receptor subtype. The compound is of interest for investigating the biological role of A2a adenosine receptors and deserves further attention to clarify the therapeutic potential of A2a antagonists.[1]

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Background: Permanent functional deficits following spinal cord injury (SCI) arise both from mechanical injury and from secondary tissue reactions involving inflammation. Enhanced release of adenosine and glutamate soon after SCI represents a component in the sequelae that may be responsible for resulting functional deficits. The role of adenosine A2A receptor in central ischemia/trauma is still to be elucidated. In our previous studies we have demonstrated that the adenosine A2A receptor-selective agonist CGS21680, systemically administered after SCI, protects from tissue damage, locomotor dysfunction and different inflammatory readouts. In this work we studied the effect of the adenosine A2A receptor antagonist SCH58261, systemically administered after SCI, on the same parameters. We investigated the hypothesis that the main action mechanism of agonists and antagonists is at peripheral or central sites. Methods: Spinal trauma was induced by extradural compression of SC exposed via a four-level T5-T8 laminectomy in mouse. Three drug-dosing protocols were utilized: a short-term systemic administration by intraperitoneal injection, a chronic administration via osmotic minipump, and direct injection into the spinal cord. Results: SCH58261, systemically administered (0.01 mg/kg intraperitoneal. 1, 6 and 10 hours after SCI), reduced demyelination and levels of TNF-α, Fas-L, PAR, Bax expression and activation of JNK mitogen-activated protein kinase (MAPK) 24 hours after SCI. Chronic SCH58261 administration, by mini-osmotic pump delivery for 10 days, improved the neurological deficit up to 10 days after SCI. Adenosine A2A receptors are physiologically expressed in the spinal cord by astrocytes, microglia and oligodendrocytes. Soon after SCI (24 hours), these receptors showed enhanced expression in neurons. Both the A2A agonist and antagonist, administered intraperitoneally, reduced expression of the A2A receptor, ruling out the possibility that the neuroprotective effects of the A2A agonist are due to A2A receptor desensitization. When the A2A antagonist and agonist were centrally injected into injured SC, only SCH58261 appeared neuroprotective, while CGS21680 was ineffective. Conclusions: Our results indicate that the A2A antagonist protects against SCI by acting on centrally located A2A receptors. It is likely that blockade of A2A receptors reduces excitotoxicity. In contrast, neuroprotection afforded by the A2A agonist may be primarily due to peripheral effects.[2]

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Purpose: To investigate the role of adenosine A2A receptors on 6-OHDA-induced motor disorder in rat. Methods: In order to induce experimental model of Parkinson's disease, 6-hydoxydopamine (8 μg/rat) was injected unilaterally into the SNc. After three weeks as a recovery period, 6-OHDA-induced bradykinesia and balance disturbances were assessed by using beam traversal test 10, 30 and 60 minutes after intraperitoneal injections of the drugs (caffeine, SCH58261). Results: The results showed that 6-OHDA (8 μg/rat, Intra-SNc) induced motor disorders of Parkinson's disease and increased elapsed time in the beam test (p<0.001). Injection of caffeine (30 mg/kg, i.p.) and SCH58261 (2 mg/kg, i.p.) attenuated elapsed time on beam (p<0.01 and p<0.001). We showed that acute administration of caffeine and SCH 58261 can improve the 6-OHDA-induced bradykinesia and motor disturbance. Conclusion: Adenosine A2AR antagonists improve 6-OHDA-motor deficit and this effect seems to be mediated by the inhibition of A2A presynaptic receptors in substantia nigra pars compacta.[3]

C18H15N7O

345.36

345.134

C, 62.60; H, 4.38; N, 28.39; O, 4.63

160098-96-4

176408

White to yellow solid powder

1.54g/cm3

1.807

3.14

1

6

4

26

488

0

O1C([H])=C([H])C([H])=C1C1=NN2C(N([H])[H])=NC3=C(C([H])=NN3C([H])([H])C([H])([H])C3C([H])=C([H])C([H])=C([H])C=3[H])C2=N1

UTLPKQYUXOEJIL-UHFFFAOYSA-N

InChI=1S/C18H15N7O/c19-18-22-16-13(11-20-24(16)9-8-12-5-2-1-3-6-12)17-21-15(23-25(17)18)14-7-4-10-26-14/h1-7,10-11H,8-9H2,(H2,19,22)

4-(furan-2-yl)-10-(2-phenylethyl)-3,5,6,8,10,11-hexazatricyclo[7.3.0.02,6]dodeca-1(9),2,4,7,11-pentaen-7-amine

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

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

Solubility in Formulation 1: ≥ 2.08 mg/mL (6.02 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (6.02 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 3: 4%DMSO + 40%PEG300 + 4%Tween 80 52%ddH2O: 2.0mg/ml (5.79mM)

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