sq-23377 and rhod-2

sq-23377 has been researched along with rhod-2* in 3 studies

Other Studies

3 other study(ies) available for sq-23377 and rhod-2

ArticleYear
Regulation of superoxide flashes by transient and steady mitochondrial calcium elevations.
    Science China. Life sciences, 2014, Volume: 57, Issue:5

    The mitochondria play essential roles in both intracellular calcium and reactive oxygen species signaling. As a newly discovered universal and fundamental mitochondrial phenomenon, superoxide flashes reflect transient bursts of superoxide production in the matrix of single mitochondria. Whether and how the superoxide flash activity is regulated by mitochondrial calcium remain largely unknown. Here we demonstrate that elevating mitochondrial calcium either by the calcium ionophore ionomycin or by increasing the bathing calcium in permeabilized HeLa cells increases superoxide flash incidence, and inhibition of the mitochondrial calcium uniporter activity abolishes the flash response. Quantitatively, the superoxide flash incidence is correlated to the steady-state mitochondrial calcium elevation with 1.7-fold increase per 1.0 ΔF/F 0 of Rhod-2 signal. In contrast, large mitochondrial calcium transients (e.g., peak ΔF/F 0 ∼ 2.8, duration ∼ 2 min) in the absence of steady-state elevations failed to alter the flash activity. These results indicate that physiological levels of sustained, but not transient, mitochondrial calcium elevation acts as a potent regulator of superoxide flashes, but its mechanism of action likely involves a multi-step, slow-onset process.

    Topics: Aniline Compounds; Calcium; Calcium Channels; Calcium Ionophores; Calcium Signaling; Fluorescent Dyes; Gene Knockdown Techniques; HeLa Cells; Heterocyclic Compounds, 3-Ring; Humans; Ionomycin; Mitochondria; Reactive Oxygen Species; RNA, Small Interfering; Signal Transduction; Superoxides; Xanthenes

2014
Heterogeneity of mitochondrial matrix free ca2+: resolution of Ca2+ dynamics in individual mitochondria in situ.
    The American journal of physiology, 1999, Volume: 276, Issue:5

    The role of mitochondria in Ca2+ homeostasis is controversial. We employed the Ca2+-sensitive dye rhod 2 with novel, high temporal and spatial resolution imaging to evaluate changes in the matrix free Ca2+ concentration of individual mitochondria ([Ca2+]m) in agonist-stimulated, primary cultured aortic myocytes. Stimulation with 10 microM serotonin (5-HT) evoked modest cytosolic Ca2+ transients [cytosolic free Ca2+ concentration ([Ca2+]cyt) <500 nM; measured with fura 2] and triggered contractions in short-term cultured myocytes. However, 5-HT triggered a large mitochondrial rhod 2 signal (indicating pronounced elevation of [Ca2+]m) in only 4% of cells. This revealed heterogeneity in the responses of individual mitochondria, all of which stained with MitoTracker Green FM. In contrast, stimulation with 100 microM ATP evoked large cytosolic Ca2+ transients (>1,000 nM) and induced pronounced, reversible elevation of [Ca2+]m (measured as rhod 2 fluorescence) in 60% of cells. This mitochondrial Ca2+ uptake usually lagged behind the cytosolic Ca2+ transient peak by 3-5 s, and [Ca2+]m declined more slowly than did bulk [Ca2+]cyt. The uptake delay may prevent mitochondria from interfering with rapid signaling events while enhancing the mitochondrial response to large, long-duration elevations of [Ca2+]cyt. The responses of arterial myocytes to modest physiological stimulation do not, however, depend on such marked changes in [Ca2+]m.

    Topics: Adenosine Triphosphate; Animals; Aorta; Calcium; Cells, Cultured; Cytosol; Fluorescent Dyes; Heterocyclic Compounds, 3-Ring; Ionomycin; Ionophores; Mitochondria; Muscle Contraction; Muscle, Smooth, Vascular; Rats; Rats, Sprague-Dawley; Serotonin

1999
Calcium extrusion by the sodium-calcium exchanger of the human platelet.
    Annals of the New York Academy of Sciences, 1991, Volume: 639

    Topics: Blood Platelets; Calcium; Carrier Proteins; Fluorescent Dyes; Heterocyclic Compounds, 3-Ring; Humans; In Vitro Techniques; Ionomycin; Kinetics; Monensin; Sodium-Calcium Exchanger

1991