Role of activation of astrocytes in spinal cord in myocardial ischemia-reperfusion injury in rats / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the role of activation of astrocytes in the spinal cord in myocardial ischemia-reperfusion (I/R) injury in rats.Methods Eighteen healthy adult male Sprague-Dawley rats,in which intrathecal catheters were successfully implanted,weighing 250-300 g,were divided into 3 groups (n =6 each) using a random number table method:sham operation group (group Sham),myocardial I/R group (group I/R) and an astrocyte inhibitor fluorocitrate group (group I/R+FC).Myocardial ischemia was induced by 30 min occlusion of left anterior descending branch of coronary artery followed by 120 min reperfusion in chloral hydrate-anesthetized rats.Fluorocitrate 10 μl (1 nmol) was intrathecally infused at a constant rate starting from 30 min before ischemia in group I/R+ FC.Arrhythmia was scored according to the results of electrocardiography during I/R.Arterial blood samples were collected at 120 min of reperfusion to determine the serum cardiac troponin Ⅰ (cTnⅠ) concentration by chemiluminescence assay.The animals were then sacrificed,myocardial specimens were taken for measurement of the infarct size,and T2-6 segments of the spinal cord were harvested for determination of the expression of glial fibrillary acidic protein (GFAP) (by Western blot).Results Compared with group Sham,the serum cTnⅠ concentration,arrhythmia score,and myocardial infarct size were significantly increased,and the expression of GFAP was up-regulated in I/R and I/R+FC groups (P＜0.05).Compared with group I/R,the serum cTnⅠ concentration,arrhythmia score,and myocardial infarct size were significantly decreased,and the expression of GFAP was down-regulated in group I/R+FC (P＜0.05).Conclusion The activation of astrocytes in spinal cord is involved in myocardial I/R injury in rats.