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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS. Meshes: Animals, Calcium Channels, L-Type, Cell Line, Electron Transport Chain Complex Proteins, Humans, Lipoproteins, LDL, Lysophosphatidylcholines, Mitochondria, Myocytes, Cardiac, Patch-Clamp Techniques, Rats, Reactive Oxygen Species.
user
Does oxLDL enhance L-type Ca2+ currents via lysophosphatidylcholine-induced mitochondrial reactive oxygen species ( ROS ) production? Context: To examine the mechanisms underlying oxidised LDL- (oxLDL)-induced alterations in Ca(2+) currents, an effect which underlies altered vascular contractility and cardiac myocyte function. Ca(2+) currents (I(Ca)) were recorded by whole-cell patch-clamp in HEK293 cells expressing L-type Ca(2+) channel alpha(1C) subunits or isolated rat ventricular myocytes. oxLDL (but not native LDL) significantly enhanced recombinant I(Ca), an effect mimicked by 1 microM lysophosphatidylcholine (LPC). LPC failed to enhance I(Ca) either in mitochondrial electron transport chain-depleted rho(0) cells, or in the presence of rotenone (1 microM), or MPP(+) (10 microM). The LPC response was similarly ablated by ascorbate (200 microM) or TROLOX (500 microM) and by the mitochondria-targeted antioxidant, MitoQ (250 nM). In myocytes, enhancement of I(Ca) due to LPC was similarly abrogated with rotenone and MitoQ. These data suggest that LPC enhanced recombinant Ca(2+) currents due to increased mitochondrial ROS production. In support with this, LPC enhanced fluorescence in HEK293 cells and cardiac myocytes loaded with a ROS-sensitive mitochondrial dye, reduced mitotracker red.
assistant
LPC up-regulates L-type Ca(2+) currents due to altered mitochondrial ROS production, an effect which mediates the response of the native I(Ca) in cardiac myocytes to oxLDL. Final Decision: yes