NMDA Receptor

DL-AP5 (100 μM) partially prevents glutamate-induced increase in Arc/Arg3.1 protein levels[5]. DL-AP5 decreases the NMDA-induced Arc/Arg3.1 upregulation[5].

DL-AP5 (0-10 μg/rat, Intra-CA1) significantly decreases the effect of NMDA[3]. DL-AP5 (0-10 nmol, Intracerebroventricular injection) causes a dose-dependent increase in food consumption[4]. DL-AP5 (5 nmol, Intracerebroventricular injection) attenuates the decreased food consumption induced by the intracerebroventricular injection of ghrelin[4].

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While much evidence implicates substance P (SP), an endogenous neurokinin (NK), as a primary sensory transmitter of acute pain in mammalian spinal cord, its role in continuous (tonic) pain is less clear. Although glutamate is co-localized with SP in dorsal root ganglion neurons, its role in nociceptive processing is uncertain. While antagonists of NKs and excitatory amino acids (EAAs) have been found to be antinociceptive in some acute assays, they have not been tested against tonic pain. We hypothesize that: (1) NKs and EAAs contribute to signaling of tonic chemogenic nociception; and (2) interaction between NK and EAA systems is important in determining the perceived intensity of a continuous noxious stimulus. We therefore evaluated two NK antagonists ([D-Pro2,D-Trp7,9] SP (DPDT-SP, 0.26-6.6 nmoles, non-specific) and [D-Pro4, D-Trp7,9,10,Phe11]-SP(4-11) (DPDTP-octa, 1.6-12.3 nmoles, somewhat NK-1 selective], as well as DL-2-amino-5-phosphonovalerate (DL-AP5, NMDA antagonist, 0.05-1 nmole) and urethane (a kainic acid (KA) antagonist at 2.5 mumoles) for antinociceptive activity in the mouse formalin model. Administered intrathecally (i.t.), DL-AP5 and both NK antagonists were significantly antinociceptive while urethane (2.5 mumoles) and naloxone (2.7 nmoles) were inactive. A50 values for mean % analgesia, nmoles/mouse i.t. (95% CLs) were: DPDT-SP, 1.1 (0.79-1.6); DPDTP-octa, 3.9 (2.4-6.1); DL-AP5, 0.29 (0.16-0.71). The antinociception associated with 1.3 nmoles of DPDT-SP was not reversed by co-administering 2.7 nmoles of naloxone. Co-administration of 0.1 nmoles of DL-AP5 with either 1.3 nmoles of DPDT-SP or 3.3 nmoles of DPDTP-octa did not lead to additive antinociception.[1]

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This study was designed to examine the effects of intracerebroventricular injection of DL-AP5 (N-methyl-D-aspartate (NMDA) receptor antagonist) and glutamate on ghrelin-induced feeding behavior in 3-h food-deprived (FD3) broiler cockerels. At first, guide cannula was surgically implanted in the right lateral ventricle of chickens. In experiment 1, birds were intracerebroventricularly injected with 0, 2.5, 5, and 10 nmol of DL-AP5. In experiment 2, chickens received 5 nmol DL-AP5 prior to the injection of 0.6 nmol ghrelin. In experiment 3, birds were administered with 0.6 nmol ghrelin after 300 nmol glutamate, and the cumulative feed intake was determined at 3-h postinjection. The results of this study showed that the intracerebroventricular injection of DL-AP5 increased food consumption in FD3 broiler cockerels (P ≤ 0.05), and this increase occurs in a dose-dependent manner. Moreover, the decreased food intake induced with the intracerebroventricular injection of ghrelin was additively enhanced by pretreatment with glutamate, and this effect was attenuated by DL-AP5 administration(P ≤ 0.05).These results suggest that there is an interaction between ghrelin and glutamatergic system (through NMDA receptor) on food intake in broiler cockerels.[4]

1. Intracellular and extracellular recordings were obtained from ganglion cells in the rabbit retina. The effect of N-methyl-DL-aspartate (NMDLA) and N-methyl-D-aspartate (NMDA) antagonists were studied with the use of a perfusion method for drug application. 2. NMDLA excited all ganglion cell types and caused a characteristic burst firing pattern, which is not typical of physiological responses in the retina. When synaptic transmission was blocked with cobalt, NMDLA still excited ganglion cells, indicating a direct action. 3. A comparison of DL-2-amino-5-phosphonopentanoate (DL-AP-5) and DL-2-amino-7-phosphonoheptanoate (DL-AP-7) revealed that DL-AP-7 was a more specific NMDA antagonist. DL-AP-5 partially blocked the b-wave of the electroretinogram (ERG), an action typical of L-2-amino-4-phosphonobutyrate (L-APB), which specifically blocks on channels in the retina. 4. DL-AP-7 reversibly blocked the action of NMDLA on all ganglion cell types, but the effects of kainate (KA) and carbachol were unchanged. AP-7 was stereospecific and pharmacologically specific, with action typical of a competitive NMDA antagonist in the rabbit retina. 5. DL-AP-7 did not block light responses driven by center or surround stimulation for ON or OFF ganglion cells. Directional selectively was unchanged by DL-AP-7. However, most ganglion cells showed a reduction, typically 20-30%, in the number of action potentials produced by light stimulation. 6. In contrast to a previous report, we found no evidence that DL-AP-7 specifically inhibited sustained ON ganglion cells. The inhibition of sustained ON responses by DL-AP-5, previously attributed to NMDA antagonism, is probably because of the weak APB activity of L-AP-5. 7. We conclude that NMDA receptors do not mediate the major light-driven input to ganglion cells in the rabbit retina. By exclusion, transmission from bipolar cells to ganglion cells appears to be carried mostly by KA or quisqualate (QQ) receptors. However, because NMDA antagonists reduced the number of action potentials produced by light stimulation, it is likely that NMDA receptors carry a portion of the signal transmission to ganglion cells. The presence of NMDA receptors on third-order neurons is consistent with the release of glutamate from presynaptic neurons such as bipolar cells.[2]

Animal/Disease Models: Male Wistar rats (180-230 g)[3]
Doses: 1, 3.2 and 10 μg/rat
Route of Administration: Injected into the intra-dorsal hippocampal (intra-CA1) immediately after shock administration, once
Experimental Results: Significantly decreased the effect of NMDA (10-2 μg/rat, intra-CA1) with significant interaction.

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Animal/Disease Models: Broilers cockerels (3-h fooddeprived (FD3), n=8 for each group)[4]
Doses: 0, 2.5, 5, and 10 nmol; in a volume of 10 μL
Route of Administration: Intracerebroventricular injection
Experimental Results: Caused a dose-dependent increase in food consumption which was significant for 5 and 10 nmol doses.

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Animal/Disease Models: Broilers cockerels (3-h fooddeprived (FD3), n=8 for each group)[4]
Doses: 5 nmol
Route of Administration: Intracerebroventricular injection, followed by ghrelin (0.6 nmol)
Experimental Results: Attenuated the decreased food consumption induced by the intracerebroventricular injection of ghrelin.

[1].Neurokinin and NMDA antagonists (but not a kainic acid antagonist) are antinociceptive in the mouse formalin model. Pain. 1991;44(2):179-185.

[2].N-methyl-D-aspartate receptors of ganglion cells in rabbit retina. J Neurophysiol. 1990;63(1):16-30.

[3].NMDA receptor blockers prevents the facilitatory effects of post-training intra-dorsal hippocampal NMDA and physostigmine on memory retention of passive avoidance learning in rats. Behav Brain Res. 2006 Apr 25;169(1):120-7.

[4].The effects of DL-AP5 and glutamate on ghrelin-induced feeding behavior in 3-h food-deprived broiler cockerels. J Physiol Biochem. 2011 Jun;67(2):217-23.

[5].Glutamate-induced rapid induction of Arc/Arg3.1 requires NMDA receptor-mediated phosphorylation of ERK and CREB. Neurosci Lett. 2017 Nov 20;661:23-28.

In the present study, the effects of post-training intra-dorsal hippocampal (intra-CA1) injection of an N-methyl-D-aspartate (NMDA) receptor agonist and competitive or noncompetitive antagonists, on memory retention of passive avoidance learning was measured in the presence and absence of physostigmine in rats. Intra-CA1 administration of lower doses of the NMDA receptor agonist NMDA (10(-5) and 10(-4) microg/rat) did not affect memory retention, although the higher doses of the drug (10(-3), 10(-2) and 10(-1) microg/rat) increased memory retention. The greatest response was obtained with 10(-1) microg/rat of the drug. The different doses of the competitive NMDA receptor antagonist DL-AP5 (1, 3.2 and 10 microg/rat) and noncompetitive NMDA receptor antagonist MK-801 (0.5, 1 and 2 microg/rat) decreased memory retention in rats dose dependently. Both competitive and noncompetitive NMDA receptor antagonists reduced the effect of NMDA (10(-2) microg/rat). In another series of experiments, intra-CA1 injection of physostigmine (2, 3 and 4 microg/rat) improved memory retention. Post-training co-administration of lower doses of NMDA (10(-5) and 10(-4) microg/rat) and physostigmine (1 microg/rat), doses which were ineffective when given alone, significantly improved the retention latency. The competitive and noncompetitive NMDA receptor antagonists, DL-AP5 and MK-801, decreased the effect of physostigmine (2 microg/rat). Atropine decreased memory retention by itself and potentiated the response to DL-AP5 and MK-801. In conclusion, it seems that both NMDA and cholinergic systems not only play a part in the modulation of memory in the dorsal hippocampus of rats but also have demonstrated a complex interaction as well.[3]

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Arc/Arg3.1 is a unique immediate early gene whose expression is highly dynamic and correlated with various forms of synaptic plasticity. Many previous reports highlight the complexity of mechanisms that regulate Arc/Arg3.1 expression in neurons. In the present study, the expression and regulation of Arc/Arg3.1 after glutamate treatment in primary cultured cortical neurons were investigated. We found that both Arc/Arg3.1 mRNA and Arc/Arg3.1 protein dynamically increased within 24h after glutamate treatment. The results of immunostaining showed that abundant amounts of Arc/Arg3.1 protein are presented in both soma and dendrites. The glutamate-induced increase in Arc/Arg3.1 protein levels was partially prevented by the NMDAR inhibitor DL-AP5, but not the AMPAR inhibitor NBQX. The results of calcium imaging showed that glutamate induced significant increases in intracellular calcium levels in a NMDAR-dependent manner. However, the intracellular calcium chelator BAPTA-AM had no effect on glutamate-induced upregulation of Arc/Arg3.1 protein, and alteration of cytosolic calcium ion homeostasis with A23187 and TG did not change Arc/Arg3.1 protein levels. In addition, the phosphorylation of ERK and CREB, two downstream factors of NMDAR signaling, markedly increased after glutamate exposure. Blocking ERK and CREB activation via selective inhibitors partially prevented the glutamate-induced elevation of Arc/Arg3.1 protein levels. Combined observations support a NMDAR-mediated and calcium-independent mechanism by which glutamate increases Arc/Arg3.1 expression in cortical neurons.[5]

C5H11NNAO5P

219.11

219.027

1303993-72-7

52974251

White to off-white solid powder

3

6

5

13

211

0

KWRCYAPNGUCHOE-UHFFFAOYSA-M

InChI=1S/C5H12NO5P.Na/c6-4(5(7)8)2-1-3-12(9,10)11;/h4H,1-3,6H2,(H,7,8)(H2,9,10,11);/q;+1/p-1

sodium;(4-amino-4-carboxybutyl)-hydroxyphosphinate

DL-AP5 Sodium salt; 1303993-72-7; sodium;(4-amino-4-carboxybutyl)-hydroxyphosphinate; dl-2-amino-5-phosphonopentanoic acid sodium salt; D-LAP5.Na; C5H11NNaO5P;

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)

Typically soluble in DMSO (e.g. 10 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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