严重烧伤早期心肌收缩性与钙转运动能变化

研究烧伤早期心肌肌浆网钙转运动能变化，探讨其在烧伤后心肌收缩功能下降发病中的作用。方法 采用３０％ＴＢＳＡⅢ度烧伤大鼠模型，离体心脏灌流，测定伤前及伤后心肌室内压最大变化速度变化，制备心肌肌浆网，应用微孔滤膜过滤技术测定心肌ＳＲ＾４５Ｃａ＾２＋转运活性及ＳＲ＾５Ｃａ６２＋摄取初速度，摄取容量均明显降低，偶联率比对照值大幅度下降。

Myocardial contractile and calcium transport function after severe burn injury]

OBJECTIVE: This study examined the changes in myocardial calcium transport function and what roles it played in cardiac dysfunction after severe burn injury. METHODS: Contraction relaxation properties of the left ventricule (LV) were studied in isolated heart preparations of Wistar rat 3, 8, 24 hours after 30% TBSA full thickness burn. Sarcoplasmic reticulum (SR) calcium transport function was measured by millipore filtration technique. RESULTS: The maximal rates of LV pressure elevation (+ dp/ dtmax) and depression (-dp/dtmax) in burn group were significantly lower than that in control group (P < 0.01). The initial rate and capacity of calcium uptake by SR decreased markedly in burn group than in control group (P < 0.01). In addition, calcium dependent ATPase activity and coupling ratio of SR were also markedly depressed. CONCLUSION: SR calcium transport function depression was closely related to cardiac contractile dysfunction, and the former is one of the important mechanism for cardiac contractile dysfunction after severe burn injury.