RESUMO
Objective To evaluate the effect of dexmedetomidine pretreatment on contents of glu-tamic acid and γ-aminobutyric acid during focal cerebral ischemia-reperfusion ( I∕R) in rats. Methods Thirty-six clean-grade healthy male Wistar rats, aged 10 months, weighing 250-300 g, were divided into 3 groups using a random number table method: sham operation group (group S), I∕R group, and dexme-detomidine group (group D). Focal cerebral I∕R was induced by occlusion of the left middle cerebral artery for 30 min followed by reperfusion in anesthetized rats. The left middle cerebral artery was only isolated but not occluded in group S. Sterile normal saline 1 ml was intraperitoneally injected, and 30 min later the model of focal cerebral I∕R was established in group I∕R. Rats were sacrificed at the end of reperfusion, and brains were removed for determination of contents of glutamic acid and γ-aminobutyric acid in brain tis-sues and for examination of ultrastructure (with an electron microscope). Results Compared with group S, the content of glutamic acid was significantly increased, and the content of γ-aminobutyric acid was de-creased in I∕R and D groups (P＜0. 05). Compared with group I∕R, the content of glutamic acid was signif-icantly decreased, and the content of γ-aminobutyric acid was increased in group D (P＜0. 05). The dam-age to the ultrastructure of brain tissues was significantly attenuated in group D when compared with group I∕R. Conclusion Dexmedetomidine pretreatment can reduce focal cerebral I∕R injury through decreasing the content of glutamic acid and increasing the content of γ-aminobutyric acid in rats.
RESUMO
Objective The aim of this study was to determine the effects of ulinastatin, a broad spectrum proteinase inhibitor, on fibrinolytic system and platelet function during open heart surgery performed with cardiopulmonary bypass (CPB) .Methods Twenty ASA Ⅰ-Ⅱpatients of both sexes undergoing cardiac surgery under CPB were randomly divided into two groups of ten patients: control group(C) and ulinastatin group (U). In group U patients received ulinastatin 12 000 U?2kg-1 . Half of the dose was given iv 10 min before CPB and the other half was added to the priming solution. In group C patients received normal saline instead of ulinastatin. Blood samples were taken before CPB (T1 ) , 30 min after CPB was started (T2), at the end of CPB (T3), 2 h and 4 h after CPB(T4 , T5) for determination of plasma levels of D-Dimer, ?-granule membrane protein-140 (GMP-140), thromboxane B2 (TXB2) and 6-Keto-prostaglandin F1? (6-Keto-PGF1?) .Results The demographic data, aortic cross-clamping time, CPB time and duration of operation were comparable between the two groups. The plasma levels of D-Dimer, GMP-140, TXB2 and TXB2/6-Keto-PGFl? were significantly increased at T2 , T3 and T4 as compared with the baseline (T1 ) in both groups, but the increase was significantly larger in group C than in group U(P
RESUMO
Objective To investigate the protective effect of ulinastatin on myocardium against ischemia-reperfusion injury in open heart surgery with cardiopulmonary bypass (CPB) .Methods Twenty ASA Ⅰ - Ⅱ patients undergoing atrioseptopexy or surgical repair of VSD under CPB were randomly divided into two groups: in ulinastatin group (U n = 10) patients received ulinastatin 12000 unit?kg-1, half of the dose was given iv, 10 min before aorta cannulation and another half was added into the priming fluid; in control group (C n = 10) the patients received same volume of saline instead of ulinastatin. Premedication consisted of intramuscular pethidine 1 mg?kg-1 and scopolamine 0.01 mg?kg-1 .Anesthesia was induced with midazolam 0.1 mg?kg-1, fentanyl 10 ?g?kg-1 and pancuronium 0.1 mg**kg-1 and maintained with fentanyl, enflurane or isoflurane, diazepam and pancuronium. Arterial blood samples were taken before CPB (T1), at release of the aortic cross-clamp (T2), 30 min after aortic release (T3), 4h and 24h after discontinuation of CPB (T4, T5 ) for determination of plasma levels of cardiac troponin I (cTnI), creatine phosphokinase (CK) and creative phosphokinase isoenzyme (CK-MB) .Results The demographic data were comparable between the two groups. The CPB time, aortic cross-clamping time and duration of operation were also comparable. The plasma cTnI level and CK, CK-MB activity were all within normal range before CPB in both groups. In group C the plasma level of cTnI started increasing at T2, peaked at T4 and started decreasing at T5. In group U the plasma level of cTnI at T3 and T4 was significantly higher than the baseline (P