Abstract: Aim The cardio to xicity profile of sodium γ-hydroxy butyrate and ketamine was investigated.Methods 4 day-old cultured neonatal primary my ocardial cells obtained from 2to3-day-old Wistar rats were divided into 5 groups, with group C serving as control and groups HL, HH, KL and KH treated with sodium γ-hydroxy butyrate (3×10^-3 mol·L^-1 and 3×10^-2 mol·L^-1) and ketamine (1×10^-5 mol·L^-1 and 1×10^-4 mo l·L^-1)for 8 h. The contractility、morphology and cytoplasmic enzyme (LDH,AST, CK and ALP)release of my ocardial cell and the concentration of elect rolytes (K⁺, Na⁺, Cl-and Ca²⁺)in the medium were measured 8 h following the intrav enous anesthetics administ ration.Results In group KL, the beatingrate of neonatal my ocardial cell was increased (P<0.05), while in group KH decreased significantly (P<0.05).The release of LDH and AST in the cell cultures of group KH was increased and ALP decreased (P<0.05)associated with an adve rse effect on morphology.The results show that group HL, HH and KL had little or no effect on all indices of toxicity evaluated electrolytes were not significantly different between groups. Conclusion The high concent rations of ketamine has significant direct myocardial depressant action, while sodium γ-hydroxy butyrate and low concent rations of ketamine have little or no effect on cardio to xity, in fact, the low concent rations of ketamine has positive chronot ropic and inot ropic action.

Key words: sodium γ-hydroxybutyrate, ketamine, my ocardium, cy to toxicity, cell culture