NOS3 (Ab-1177) Antibody
Description
Product Overview
NOS3 (Ab-1177) Antibody is a polyclonal rabbit antibody targeting endothelial nitric oxide synthase (eNOS), a key enzyme in vascular nitric oxide (NO) production. It is directed against a peptide sequence spanning amino acids 1175–1179 (T-Q-S-F-S) of human eNOS. This antibody is widely used in research to study eNOS expression, localization, and activity in endothelial cells .
| Parameter | Value |
|---|---|
| Immunogen | Peptide (aa. 1175–1179) |
| Host | Rabbit |
| Reactivity | Human, Mouse, Rat |
| Applications | Western Blotting (WB), IF |
| Predicted MW | 140 kDa |
Research Findings
The antibody has been instrumental in studying genetic variations of NOS3, particularly the Glu298Asp polymorphism (rs1799983), which alters eNOS function. In a landmark study, Joshi et al. (2007) used Ab-1177 to demonstrate that Asp variants exhibit reduced caveolar membrane enrichment and impaired association with caveolin-1 (Cav-1) . Key findings include:
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Caveolar Localization: Asp variants showed ~40% lower NOS3 enrichment in caveolar fractions compared to Glu/Glu genotypes (P < 0.05) .
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Shear Stress Response: Asp variants exhibited defective NOS3/Cav-1 dissociation under shear stress, correlating with reduced NOx production (P < 0.05) .
These results highlight the antibody’s utility in linking genetic variants to functional outcomes, such as endothelial dysfunction .
Applications and Validation
Western Blotting (WB)
Immunofluorescence (IF)
Customer Feedback:
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A verified user confirmed detection of eNOS in human spleen lysates using WB .
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Another study reported positive staining in placental tissues, consistent with literature on NOS3 expression .
References
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Cepham Life Sciences. (2020). eNOS(Ab-1177) Antibody.
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Joshi et al. (2007). Biochemical consequences of the NOS3 Glu298Asp variation in human endothelium. Journal of Clinical Investigation.
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Boster Bio. (2020). Anti-eNOS (Ab-1177) NOS3 Antibody.
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Antibodies.com. (2015). Anti-eNOS (Ab-1177) Antibody (A39331).
Product Specs
Target Background
- The NOS3 895(G>T) polymorphism is significantly associated with recurrence-free survival in patients who received intravesical chemotherapy with pirarubicin after complete transurethral resection. PMID: 30125887
- In human gastric cancer tissues, low BUBR1 expression was found to be correlated with the absence of eNOS expression. A decrease in BUBR1 reduced eNOS bioavailability through a pathway independent of eNOS phosphorylation. PMID: 30396924
- Research suggests that overexpressing or activating eNOS in epithelial ovarian cancers enhances their survival and promotes their ability to regulate smooth muscle cell migration through paracrine effects. PMID: 29343714
- A study examining the relationship between renal colic and endothelial nitric oxide synthase gene polymorphisms found no association. PMID: 28802544
- MicroRNAs miR-195 and miR-582 regulate NO release by targeting the 3'-UTR of NOS3 post-transcriptionally in endothelial cells. PMID: 29948755
- Binding of IL-5 to IL-5Ralpha receptors enhances angiogenic responses by stimulating the expression of HSP70-1 via the eNOS signaling pathway. PMID: 28317868
- Studies indicate that XBP1 splicing can regulate eNOS expression and cellular location, contributing to endothelial cell migration, wound healing, and angiogenesis. PMID: 29352987
- An unfavorable genotype of the polymorphic variant of the NOS3 gene (T786C) is associated with alterations in the levels of active substances in individuals exposed to mercury. PMID: 30351652
- The 4a/b polymorphism of the NOS3 gene in patients with various stages of pneumoconiosis correlates with early development and an unfavorable course of the disease during the post-contact period. PMID: 30351692
- Research suggests that infants with the GT genotype of the eNOS 894G > T polymorphism have a 3.4-fold higher risk of developing intraventricular hemorrhage if born before 28 + 6 weeks of gestation. PMID: 28211916
- Immunoprecipitation studies have demonstrated a physical interaction between p38 and eNOS, suggesting a novel, NO-independent mechanism for eNOS regulation of TLR4. Biopsy samples from patients with systemic lupus erythematosus show reduced eNOS expression with associated elevations in TLR4 and p38, suggesting an in vivo link. PMID: 29061842
- Findings indicate a negative regulatory association between miR24 and NOS3. Downregulation of NOS3 may induce vasospasm following subarachnoid hemorrhage, potentially due to the upregulation of miR24 in vascular smooth muscle cells. PMID: 29845232
- A significant relationship was found between eNOS gene polymorphisms and congenital heart defects in patients with Down syndrome. Screening for eNOS polymorphisms may provide preliminary data on the risk of congenital heart defects in this population. PMID: 30204958
- Research suggests that common genetic polymorphisms in the eNOS gene contribute to the risk of erectile dysfunction, potentially through effects on eNOS activity and NO availability. PMID: 29654965
- ZYZ-803, a cardioprotective agent, stimulates the expression of cystathionine gamma-lyase (CSE) for H2S generation and the activity of endothelial NO synthase (eNOS) for NO production. Blocking CSE and/or eNOS suppresses ZYZ-803-induced H2S and NO production and cardioprotection. PMID: 29288927
- A meta-analysis found that the eNOS CC genotype was not associated with a higher susceptibility to migraine compared to TT+ TC genotypes. Subgroup analysis revealed that the CC variant increases the risk of migraine compared to TT+ TC genotypes in Caucasian populations, but not in non-Caucasian populations. No significant differences were observed for other genotypes and alleles between migraine patients and healthy controls. PMID: 30200152
- This study suggests that type 2 diabetes patients with different genotypes at CD36, NOS3, and PPARG respond differentially to omega-3 supplement intervention in blood lipid profiles. PMID: 29703528
- The effect of statins on the expression of sirtuin 1 (SIRT1) and endothelial nitric oxide synthase 3 (eNOS) proteins in young premature myocardial infarction (PMI) patients was investigated. Findings showed that PMI patients taking statins had significantly higher SIRT1 levels compared to controls. The level of eNOS protein was considerably lower in PMI patients compared to the control group. PMID: 29664427
- The eNOS-Glu298Asp variant (in both mothers and newborns), in association with dyslipidemia (increased cholesterol, LDL, and TG levels, and decreased HDL levels), could affect NO bioavailability and represent an increased risk for preeclampsia. PMID: 28486825
- Increased levels of nitric oxide in men with arterial hypertension were not dependent on the polymorphic genotypes GG and GT of the eNOS gene. PMID: 29658078
- The C allele of the eNOS SNP 786 T/C rs2070744 was independently associated with an increased risk of cardiac instability following aneurysmal subarachnoid hemorrhage. PMID: 29079038
- A reduction in eNOS and VEGF expression from baseline to the first clinical evaluation may indicate a response to bevacizumab. PMID: 28465540
- The combined effect of polymorphisms in EDNRB and NOS3 on diabetic retinopathy risk was greater than the individual effect of each polymorphism in the analyzed genetic models. PMID: 28817788
- Polymorphisms in the eNOS "A/A" (homozygous mutant) and ACE "I/D" genotypes might contribute to the increased risk of non-small cell lung cancer in the South Indian population. PMID: 27328622
- The eNOS G894T gene polymorphism was associated with the occurrence and development of coronary heart disease in young individuals. PMID: 29359785
- The frequency of the T allele of the eNOS gene in type 2 diabetes was less common than in controls. PMID: 28499789
- Findings suggest that the tandem repeat variant within intron 4 of the NOS3 gene is associated with an increased risk of infertility in men diagnosed with idiopathic oligoasthenozoospermia. PMID: 28466478
- Upregulation of placenta-associated serum exosomal miR155 from patients with preeclampsia may suppress endothelial nitric oxide synthase (eNOS) expression in endothelial cells. PMID: 29328396
- The eNOS gene SNP rs1808593 genotype may play a significant role in predicting the occurrence of pediatric systemic lupus erythematosis and central nervous system complications in pSLE. PMID: 29465350
- Research suggests that NOS3 polymorphisms and physical training are important interacting variables to consider when evaluating redox status, nitric oxide availability and production, and blood pressure control. PMID: 29104725
- The eNOS rs1799983 polymorphism and T rs1799983C rs2070744 haplotype might reduce the risk of immunoglobulin A nephropathy in Chinese populations. PMID: 28946141
- A novel mechanism for the regulation of eNOS uncoupling by low shear stress via autophagy-mediated eNOS phosphorylation has been reported, which is implicated in the geometrical nature of atherogenesis. PMID: 29466710
- NOS3 SNPs are associated with post-exercise hypotension in an ethnicity and exercise intensity-dependent manner. PMID: 29180482
- Acidic pH reduces NO synthesis and eNOS serine(1177) phosphorylation. Therefore, system y(+)L activity is downregulated by an acidic pH, a phenomenon that may result in reduced NO synthesis in human umbilical vein endothelial cells. PMID: 29410170
- A meta-analysis did not detect any association between the eNOS 27VNTR (4b/4a) polymorphism and diabetic microvascular complications susceptibility in Chinese populations. PMID: 29096758
- Pitavastatin increases eNOS expression and inhibits LPS-induced miR-155 expression to prevent inflammation in human umbilical vein endothelial cells. PMID: 28664667
- The 27-bp VNTR polymorphism in intron 4 of the eNOS gene polymorphism may be a significant risk factor for systemic lupus erythematosus in South Indian subjects. PMID: 29524578
- Findings provide evidence supporting the hypothesis that the eNOS -786 T>C polymorphism and the -786C-4a-894G haplotype are associated with a high risk of recurrent pregnancy loss. PMID: 28605668
- 6-Gin attenuated the injury of human umbilical vein endothelial cells induced by high glucose through the activation of the PI3K-AKT-eNOS signaling pathway. PMID: 28709132
- The two single nucleotide polymorphisms in the eNOS gene, G894T and T-786C, are strongly associated with the risk of erectile dysfunction (meta-analysis). PMID: 26908069
- Extracellular histones disrupt vasoactive mediator release through a COX1-COX2-eNOS interaction in human endothelial cells. PMID: 28244682
- The rs1799983 NOS3 polymorphism could be associated with hypertension and diastolic blood pressure among Southern Europeans. This association is influenced by dietary fat (saturated fatty acids and monounsaturated fatty acids) and body mass index. PMID: 26994605
- The T786C eNOS mutation is common among patients with primary osteonecrosis. PMID: 28877324
- Mechanical perturbations sensitize human red blood cell-eNOS to produce nitric oxide. PMID: 27345770
- This study is the first to describe the effects of eNOS polymorphisms on different forms of sickle cell disease, the first to enroll sickle cell disease patients of Caucasian origin, and the first to determine eNOS mRNA levels in peripheral blood from steady-state sickle cell disease patients. PMID: 27871907
- The development of cholangiocarcinoma involves the upregulation of eNOS and P-eNOS and their regulators. This may drive angiogenesis and metastasis in cholangiocarcinoma. PMID: 27143607
- No statistically significant correlation was found between serum levels of PIN1 and systolic and diastolic blood pressure, between serum levels of eNOS and diastolic blood pressure in normotensive Alzheimer's disease patients, between serum levels of PIN1, eNOS, and systolic blood pressure, and between serum eNOS and systolic and diastolic blood pressure in patients with hypertension. PMID: 28506742
- The study showed that knockdown of VPO1 expression significantly increased serine1177 phosphorylation of eNOS, suggesting that structural changes and phosphorylation by VPO1 downregulate the expression of eNOS. PMID: 28264790
- The -786 T/C polymorphism of the NOS3 gene is a susceptibility marker of chronic obstructive pulmonary disease among Tunisians that correlates with nitric oxide levels and airflow obstruction. PMID: 28526204
- Results indicate that eNOS and XRCC4 VNTR variants may play a potential role in schizophrenia + nicotine dependence and/or nicotine dependence pathophysiology. PMID: 29050484
Q&A
Basic Research Questions
How is NOS3 (Ab-1177) antibody validated for specificity in Western blot (WB) and immunofluorescence (IF)?
Validation involves:
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Positive/Negative Controls: Testing with lysates from tissues/cells with known NOS3 expression (e.g., heart, kidney) versus knockout models .
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Blocking Peptide Competition: Pre-incubation with immunogen peptide (T-Q-S-F-S sequence) to confirm signal loss .
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Molecular Weight Verification: Expected band at ~140 kDa (predicted MW: 133–140 kDa), though post-translational modifications may shift observed MW to 39 kDa under reducing conditions .
What experimental conditions optimize NOS3 detection in WB?
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Sample Preparation: Use RIPA buffer with protease/phosphatase inhibitors to preserve phosphorylation states (critical for S1177 epitope recognition) .
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Gel Electrophoresis: 5–20% SDS-PAGE gels run at 70–90 V for 2–3 hours .
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Antibody Dilution: 1:500–1:1000 in 5% non-fat milk/TBS, incubated overnight at 4°C .
How does species reactivity impact experimental design?
The antibody recognizes human, mouse, and rat NOS3 but shows no cross-reactivity with other isoforms (e.g., iNOS, nNOS) . For non-model organisms (e.g., zebrafish), perform sequence alignment for the immunogen region (aa 1175–1179) .
Advanced Research Questions
How to resolve discrepancies between observed and predicted molecular weights?
What strategies address non-specific signals in vascular tissue samples?
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Pre-absorption: Incubate antibody with tissue lysates lacking NOS3 (e.g., spleen) .
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Titration in Hypoxic Conditions: Adjust antibody concentration (1:200–1:500) for tissues with elevated chemerin or VEGF, which upregulate NOS3 fragments .
How to design functional studies linking NOS3 (Ab-1177) detection to vascular phenotypes?
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Adipocyte-Specific Knockout Models: Use Cre-lox systems (e.g., adiponectin-Cre) to study endothelial dysfunction and hypertension .
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Ex Vivo Aorta Culture: Treat vessels with serum from KO mice ± chemerin-neutralizing antibodies to quantify remodeling markers (e.g., MMP9, collagen I) .
Data Contradiction Analysis
Why does NOS3 (Ab-1177) show variable expression in WB across tissues?
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Tissue-Specific Glycosylation: Heart and kidney lysates show stronger bands due to higher glycosylation at S1177 .
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Proteolytic Degradation: Spleen samples may require fresh protease inhibitors to prevent cleavage .
How to interpret conflicting IF results in fixed versus live cells?
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Fixation Artifacts: Methanol fixation improves epitope accessibility but may alter membrane localization. Validate with live-cell imaging .
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Antibody Cocktail Approach: Combine with caveolin-1 antibodies to confirm caveolar localization .
