title: Differential aspects in ratio measurements of [Ca(2+)](i) relaxation in cardiomyocyte contraction following various drug treatments.
abstract: This study is concerned with the analysis of the time dependency of [Ca(2+)](i), monitored by indo-1-AM, via the ratiometric time response curve R(t) as measured during contractions of spontaneous or electrical stimulated cardiomyocytes (in culture). A mathematical formulation which describes the relaxation phase of R(t) was developed. By fitting formulation to the measured data of R(t), the extraction of characteristic parameters is feasible, which may reflect the factors regulating intracellular Ca concentration. The usefulness of the suggested formulation was examined by monitoring changes induced in those parameters following the exposure of the myocytes to different drugs, among which are: caffeine, ryanodine, thapsigargin db, cyclic AMP, isoprenaline, doxorubicin, and Cl-IB-MECA.
authors.affiliation: Physics Department, The Biophysical Interdisciplinary Center for the Research and the Technology of the Cellome and The Jerome Schottenstein Center for Early Detection of Cancer, Bar-Ilan University, Ramat-Gan 52900, Israel.
authors.forename: D
authors.initials: D
authors.lastname: Fixler
authors.forename: R
authors.initials: R
authors.lastname: Tirosh
authors.forename: T
authors.initials: T
authors.lastname: Zinman
authors.forename: A
authors.initials: A
authors.lastname: Shainberg
authors.forename: M
authors.initials: M
authors.lastname: Deutsch
mesh_terms: D000241:Adenosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000465:Algorithms; D000818:Animals; D000831:Animals, Newborn; D002110:Caffeine / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D002316:Cardiotonic Agents / Q000494:pharmacology; D002478:Cells, Cultured; D002614:Chelating Agents / Q000378:metabolism; D000242:Cyclic AMP / Q000494:pharmacology; D004317:Doxorubicin / Q000494:pharmacology; D004558:Electric Stimulation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007211:Indoles / Q000378:metabolism; D007545:Isoproterenol / Q000494:pharmacology; D008962:Models, Theoretical; D009119:Muscle Contraction / Q000187:drug effects*; D009206:Myocardium / Q000166:cytology; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000378:metabolism*; D051381:Rats; D012433:Ryanodine / Q000494:pharmacology; D019284:Thapsigargin / Q000494:pharmacology
chemical_list: D002316:Cardiotonic Agents; D002614:Chelating Agents; D004791:Enzyme Inhibitors; D007211:Indoles; C059587:Indo-1 pentaacetoxymethyl ester; D012433:Ryanodine; D002110:Caffeine; D019284:Thapsigargin; D004317:Doxorubicin; D000242:Cyclic AMP; D000241:Adenosine; D007545:Isoproterenol; D002118:Calcium; C090034:2-chloro-N(6)-(3-iodobenzyl)adenosine-5'-N-methyluronamide