Abstract: Aim To investigate the cardiotoxicity of propofol and thiopental. Methods 4 day-old contracting neonatal primary myocardial cells obtained from 2-to 3-day-old Wistar rats were divided into 5 groups,with normal contrast group, and the cell cultures in groups PL,PH, TL and TH, were treated with propofol(3x 10^-5 and 3X 10^-4 mol·L) and thiopental (1X 10^-5 and 1X 10^-4 mol·L) for 8 h. The contractility and morphology of the cells were observed and the cytoplasmic enzyme (LDH, AST, CK and ALP) release content of myocardial cell and the concentration of electrolytes (K⁺, Na⁺, Cl^- and Ca²⁺) in the medium were measured 8 h after intravenous anesthetics administration.Results In group-PH and TL decreased significantly (P<0.05 and P<0.01) and the cells showed partly beating or no beating in group TH. The enzemy (LDH, AST and CK) release of the cell cultures in group TL,TH and PH was increased (P<0.05 and P<0.01) and ALP decreased, associateing with in adverse effect on morphology. The results show that group PL had litle or no effect on all indices of toxicity evaluated. Electrolytes were not significantly different, among all groups.Conclusion The low concentrations of thiopental and high concentrations of propofol have significant direct myocardial depressant action, especially the high concentrations of thiopental, while low concentrations of propofol has little or no effect on cardiotoxity.

Key words: propofol, thiopental, myocardium, cytotoxicity, cell culture