Effects of isoflurane preconditioning in the delayed phase on myocardial tumor necrosis factor alpha levels and caspase-3 protein expression in a rabbit model of ischemia-reperfusion injury.

This study aimed to investigate the protective effects and the mechanisms underlying these effects of isoflurane preconditioning in the delayed phase of myocardial ischemia-reperfusion injury. We randomly divided 30 healthy male New Zealand white rabbits into three groups with 10 rabbits in each group as follows: sham operation group (C group), ischemia-reperfusion group (I/R group), and 2.0% isoflurane preconditioning group (S group). Rabbits in the C group received thoracotomy for 160 min. Rabbits in the I/R group underwent left coronary artery occlusion for 40 min and reperfusion for 120 min. Rabbits in the S group received inhalation of 2.0% isoflurane and 100% oxygen for 2 h; after 24 h, rabbits in this group received the same treatment as that administered to rabbits in the I/R group. We examined the tumor necrosis factor alpha (TNF-α) levels in each group 20 min before occlusion of the left coronary, 20 and 40 min after occlusion of the left coronary artery, and 1 and 2 h after myocardial reperfusion. After reperfusion, immunoblotting was used to measure the myocardial caspase-3 expression levels, and the infarct size was measured using Evans blue and tetrazolium chloride staining. The levels of TNF-α and caspase-3 were lower in the S group than in the I/R group, and the myocardial infarct size decreased in the S group. Thus, isoflurane preconditioning in the delayed phase exerted protective effects by decreasing the myocardial caspase-3 expression and TNF-α production in a rabbit model of ischemia-reperfusion injury.

[Effects of katamine on cardiopulmonary bypass-induced interleukin-6 and interleukin-8 response and its significance].

OBJECTIVE: To investigate the effects of ketamine on cardiopulmonary bypass-induced IL-6 and IL-8 response. METHODS: Twenty-four adult patients undergoing cardiac valve replacement were divided into control and ketamine group (n = 12). In the ketamine group, 1 mg.kg-1 ketamine was infused intravenously at the beginning of operation and CBP. Plasma levenof IL-6 and IL-8 were measured at different time after induction of anesthesia. RESULTS: In both groups, the levels of IL-6 and IL-8 increased significantly compared with those at the time before CBP (P < 0.05), but compared with those in control groups, IL-6 and IL-8 levels decreased obviously in ketamine group(P < 0.05). CONCLUSIONS: Ketamine is effective to reduce cardiopulmonary bypass-induces IL-6 and IL-8 response and protect reperfusion myocardium.

[Effect of propofol and propofol combined with ketamine on cardiovascular system].

OBJECTIVE: To prevent blood pressure from reducing caused by injection of propofol. METHODS: Thirty patients, ASA Grade I-II, were randomly allocated into one of the two groups: Group I (Group P, n = 15) and Group II (Group K + P, n = 15), the patients received 2 mg.kg-1 propofol in Group I and 1 mg.kg-1 ketamine before equal dose of propofol in Group II. Systolic blood pressure(SBP), diastolic blood pressure(DBP), mean blood pressure and heart rate were measured before injection and 1 min, 3 min, 5 min and 10 min respectively after injection. RESULTS: Blood pressure in Group I was significantly lower than Group II. CONCLUSION: Ketamine can attenuate the hemodynamic responses to propofol.