| First Author | Thunemann M | Year | 2013 |
| Journal | Circ Res | Volume | 113 |
| Issue | 4 | Pages | 365-71 |
| PubMed ID | 23801067 | Mgi Jnum | J:213388 |
| Mgi Id | MGI:5584259 | Doi | 10.1161/CIRCRESAHA.113.301063 |
| Citation | Thunemann M, et al. (2013) Transgenic mice for cGMP imaging. Circ Res 113(4):365-71 |
| abstractText | RATIONALE: Cyclic GMP (cGMP) is an important intracellular signaling molecule in the cardiovascular system, but its spatiotemporal dynamics in vivo is largely unknown. OBJECTIVE: To generate and characterize transgenic mice expressing the fluorescence resonance energy transfer-based ratiometric cGMP sensor, cGMP indicator with an EC50 of 500 nmol/L (cGi500), in cardiovascular tissues. METHODS AND RESULTS: Mouse lines with smooth muscle-specific or ubiquitous expression of cGi500 were generated by random transgenesis using an SM22alpha promoter fragment or by targeted integration of a Cre recombinase-activatable expression cassette driven by the cytomegalovirus early enhancer/chicken beta-actin/beta-globin promoter into the Rosa26 locus, respectively. Primary smooth muscle cells isolated from aorta, bladder, and colon of cGi500 mice showed strong sensor fluorescence. Basal cGMP concentrations were < 100 nmol/L, whereas stimulation with cGMP-elevating agents such as 2-(N,N-diethylamino)-diazenolate-2-oxide diethylammonium salt (DEA/NO) or the natriuretic peptides, atrial natriuretic peptide, and C-type natriuretic peptide evoked fluorescence resonance energy transfer changes corresponding to cGMP peak concentrations of approximately 3 micromol/L. However, different types of smooth muscle cells had different sensitivities of their cGMP responses to DEA/NO, atrial natriuretic peptide, and C-type natriuretic peptide. Robust nitric oxide-induced cGMP transients with peak concentrations of approximately 1 to > 3 micromol/L could also be monitored in blood vessels of the isolated retina and in the cremaster microcirculation of anesthetized mice. Moreover, with the use of a dorsal skinfold chamber model and multiphoton fluorescence resonance energy transfer microscopy, nitric oxide-stimulated vascular cGMP signals associated with vasodilation were detected in vivo in an acutely untouched preparation. CONCLUSIONS: These cGi500 transgenic mice permit the visualization of cardiovascular cGMP signals in live cells, tissues, and mice under normal and pathological conditions or during pharmacotherapy with cGMP-elevating drugs. |
