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8020S 1 Kit (96 assays) $309.00
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Product Includes Quantity (with Count) Solution Color
cGMP Ab Coated Microwells 96 tests
cGMP-HRP Conjugate 5.5 ml Red
cGMP Standard 0.5 ml Colorless
Luminol/Enhancer Solution 3 ml Colorless
Stable Peroxide Buffer 3 ml Colorless
Sealing Tape 2 sheets
ELISA Wash Buffer (20X) 10 ml Colorless
Cell Lysis Buffer (10X) 9803 15 ml Yellowish

Product Description

The Cyclic GMP XP® Chemiluminescent Assay Kit is a competition enzyme-linked immunoassay used to determine cGMP levels in cells or tissues of interest. In this assay, cGMP found in the test sample competes with a fixed amount of HRP-linked cGMP for binding to an anti-cGMP XP® Rabbit mAb immobilized onto a 96-well plate. Following washing to remove excess sample cGMP and HRP-linked cGMP, chemiluminescent reagent is added for signal development. Because of the competitive nature of this assay, the magnitude of light emission, measured in relative light units (RLU), is inversely proportional to the quantity of sample cGMP. Measurement of light emmision using the cGMP Standard allows calculating the absolute amount of cGMP in a sample of interest.

Specificity / Sensitivity

The immunoreactivity of this kit was tested against the following: ADP, AMP, ATP, cAMP, cGMP, cIMP, cTMP, CTP, GDP, GMP, and GTP. Minor cross-reactivity was observed with cIMP, with over 100-fold higher sensitivity for cGMP compared to cIMP. No cross-reactivity was observed with any of the other factors tested. Kit sensitivity, as shown in Figure 1, demonstrates a dynamic range of 2 to 200 nM of cGMP. Changes in cellular cGMP levels following specific treatments are shown in Figure 2 (low passage RFL-6 cells).

Species Reactivity: All Species Expected

Cyclic guanosine 3’,5’-monophosphate (cGMP) is a critical and multifunctional second messenger molecule involved in many signal transduction pathways in different cell types of almost all species (1). Intracellular cGMP is generated from GTP by guanylyl cyclase (GC) and degraded through phosphodiesterase (PDE) hydrolysis (1,2). Two distinctive families of GC have been identified: soluble guanylyl cyclases (sGC) that are nitric oxide-responsive and cell membrane-bound; and particulate guanylyl cyclases (pGC) that respond to diverse extracellular agonists including peptide hormones, bacterial toxins, and free radicals (2,3). Phosphodiesterases form a superfamily of 11 isoforms with different specificity to both cyclic adenosine 3’,5’-monophosphate (cAMP) and cGMP (4). Cyclic GMP regulates cellular physiology by activating cGMP-dependent kinase, modulating cGMP-dependent ion channels or transporters, and altering its own hydrolytic degradation by PDE (1,4). Because of the diversity of its effectors, cGMP plays an important role in regulating various pathological and physiological processes, such as vascular smooth muscle motility, intestinal fluid and electrolyte homeostasis, and retinal phototransduction (1,5).

1.  Domek-Łopacińska, K. and Strosznajder, J.B. (2005) J Physiol Pharmacol 56 Suppl 2, 15-34.

2.  Lucas, K.A. et al. (2000) Pharmacol Rev 52, 375-414.

3.  Potter, L.R. et al. (2006) Endocr Rev 27, 47-72.

4.  Matsumoto, T. et al. (2003) J Smooth Muscle Res 39, 67-86.

5.  Rybalkin, S.D. et al. (2003) Circ Res 93, 280-91.

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology® is a trademark of Cell Signaling Technology, Inc.
XP® is a trademark of Cell Signaling Technology, Inc.