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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: BACKGROUND, METHODS, RESULTS. Meshes: Anesthetics, Intravenous, Animals, Cytosol, Depression, Chemical, Female, Fluorescent Dyes, Fura-2, Heart, In Vitro Techniques, Ketamine, Myocardium, Propofol, Rats, Rats, Sprague-Dawley.
user
Does propofol induce a lowering of free cytosolic calcium in myocardial cells? Context: The intravenous anaesthetic drug propofol has been shown to depress myocardial contractility. Ketamine, on the other hand, is a well-documented cardiovascular stimulant. These differences could possibly be due to different effects of the drugs on the calcium homeostasis of the myocardium. The fluorescent intracellular probe fura-2 acetoxymethyl ester (fura-2/AM) was used in this in vitro investigation to study the influence of intravenous anaesthetic drugs on free cytosolic calcium concentration in suspensions of isolated rat myocardial cells. Addition of 0.5-2.0 micrograms/mL propofol resulted in a significant and dose-dependent decrease of free cytosolic calcium concentration in the myocardial cells, while addition of 0.25-2.5 micrograms/mL ketamine did not affect this concentration significantly.
assistant
The results imply that the previously demonstrated negative inotropic effect of propofol could possibly be related to its influence on calcium availability in the myocardium. Final Decision: yes