caa a22 4500 477119182 CHVBK 20180405111631.0 cr unu---uuuuu 170330e19960901xx s 000 0 eng 10.1007/BF00420911 doi (NATIONALLICENCE)springer-10.1007/BF00420911 Role of hydroxyl radical in the oxidant H2O2-mediated Ca2+ release from pulmonary smooth muscle mitochondria [Elektronische Daten] [Sujata Roychoudhury, Sahl Ghosh, Tapati Chakraborti, Sajal Chakraborti] We sought to investigate the mechanism(s) by which the oxidant H2O2 stimulates Ca2+ release from mitochondria of bovine pulmonary vascular smooth muscle tissue and to test the hypothesis that hydroxyl radical is involved in this phenomenon. Treatment of the smooth muscle tissue with 1 mM H2O2 dramatically stimulated hydroxyl radical generation as measured by methane (CH4) production by GLC using dimethylsulfoxide (DMSO) as the substrate. Pretreatment of the mitochondria with the hydroxyl radical scavanger dimethylthiourea (DMTU) prevented the increase in CH4 production caused by H2O2. In the absence of EGTA, H2O2 caused stimulation of Ca2+ release from mitochondria occurred with a lag time of about 4 min. Addition of EGTA to Ca2+ loaded mitochondria resulted an immediate loss of Ca2+ and that has been found to be augmented by H2O2. The release of Ca2+ by H2O2 did not appear to occur with concommitant increase in sucrose entry into, K+ release from, and swelling of mitochondria when the Ca2+ cycling was prevented by EGTA. These observations suggested that H2O2-mediated Ca2+ release from bovine pulmonary vascular smooth muscle tissue mitochondria occurred (i) through the involvement of hydroxyl radical; (ii) via specific pathway(s); and (iii) did not appear to happen primarily via nonspecific ‘pore' formation. Kluwer Academic Publishers, 1996 hydroxyl radical nationallicence oxidant nationallicence hydrogen peroxide nationallicence smooth muscle tissue nationallicence mitochondria nationallicence calcium nationallicence H2O2 : hydrogen peroxide nationallicence OH· : hydroxyl radical nationallicence t-buOOH : tert-butyl hydroperoxide nationallicence CH4 : methane nationallicence GLC : gas liquid chromatography nationallicence DMTU : dimethylthiourea nationallicence EGTA : ethylene glycol bis(β-aminoethyl ether) nationallicence N : N′tetraacetic acid nationallicence DMSO : dimethyl sulfoxide nationallicence CH4 : methane nationallicence HBPS : Hank's buffered physiological saline nationallicence HEPES : N-2-hydroxyethylpiperazine-N′-2-ethane sulfonic acid nationallicence MOPS : 3-(N-morpholino)propane sulfonic acid nationallicence Tris : tris (hydroxymethyl aminomethane) nationallicence Roychoudhury Sujata Department of Biochemistry and Biophysics, University of Kalyani, 741235, Kalyani, India aut Ghosh Sahl Department of Biochemistry and Biophysics, University of Kalyani, 741235, Kalyani, India aut Chakraborti Tapati Department of Biochemistry and Biophysics, University of Kalyani, 741235, Kalyani, India aut Chakraborti Sajal Department of Biochemistry and Biophysics, University of Kalyani, 741235, Kalyani, India aut Molecular and Cellular Biochemistry Kluwer Academic Publishers 159/2(1996-09-01), 95-103 0300-8177 159:2<95 1996 159 11010 https://doi.org/10.1007/BF00420911 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00420911 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Roychoudhury Sujata Department of Biochemistry and Biophysics, University of Kalyani, 741235, Kalyani, India aut NATIONALLICENCE 700 1- Ghosh Sahl Department of Biochemistry and Biophysics, University of Kalyani, 741235, Kalyani, India aut NATIONALLICENCE 700 1- Chakraborti Tapati Department of Biochemistry and Biophysics, University of Kalyani, 741235, Kalyani, India aut NATIONALLICENCE 700 1- Chakraborti Sajal Department of Biochemistry and Biophysics, University of Kalyani, 741235, Kalyani, India aut NATIONALLICENCE 773 0- Molecular and Cellular Biochemistry Kluwer Academic Publishers 159/2(1996-09-01), 95-103 0300-8177 159:2<95 1996 159 11010 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer