کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10796117 1052694 2005 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Quantitative mathematical expressions for accurate in vivo assessment of cytosolic [ADP] and ΔG of ATP hydrolysis in the human brain and skeletal muscle
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک دانش گیاه شناسی
پیش نمایش صفحه اول مقاله
Quantitative mathematical expressions for accurate in vivo assessment of cytosolic [ADP] and ΔG of ATP hydrolysis in the human brain and skeletal muscle
چکیده انگلیسی
Magnetic Resonance Spectroscopy affords the possibility of assessing in vivo the thermodynamic status of living tissues. The main thermodynamic variables relevant for the knowledge of the health of living tissues are: ΔG of ATP hydrolysis and cytosolic [ADP], the latter as calculated from the apparent equilibrium constant of the creatine kinase reaction. In this study we assessed the stoichiometric equilibrium constant of the creatine kinase reaction by in vitro 31P NMR measurements and computer calculations resulting to be: logKCK=8.00±0.07 at T=310 K and ionic strength I=0.25 M. This value refers to the equilibrium:PCr2−+ADP3−+H+=Cr+ATP4− We also assessed by computer calculation the stoichiometric equilibrium constant of ATP hydrolysis obtaining the value: logKATP-hyd=−12.45 at T=310 K and ionic strength I=0.25 M, which refers to the equilibrium:ATP4−+H2O=ADP3−+PO43−+2H+ Finally, we formulated novel quantitative mathematical expressions of ΔG of ATP hydrolysis and of the apparent equilibrium constant of the creatine kinase reaction as a function of total [PCr], pH and pMg, all quantities measurable by in vivo 31P MRS. Our novel mathematical expressions allow the in vivo assessment of cytosolic [ADP] and ΔG of ATP hydrolysis in the human brain and skeletal muscle taking into account pH and pMg changes occurring in living tissues both in physiological and pathological conditions.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochimica et Biophysica Acta (BBA) - Bioenergetics - Volume 1708, Issue 2, 30 June 2005, Pages 164-177
نویسندگان
, , , , ,