截肢手术创伤 z-bo 2020-11-25 368

　　Objective: To investigate the changes of cardiac electrophysiology and cardiac function in rats after amputation and their relationship with endothelial nitric oxide synthase/nitric oxide (eNOS/NO) pathway.

　　Methods: The left hind limb trauma model was established and the rats were divided into normal group (only anesthesia), amputation control group, amputation 0.25h, amputation 0.5h, amputation 0.75h, amputation 1.5h, 12 rats in each group. Electrocardiogram (ECG) Detection of rat heart rate, QT interval, PR interval changes; Ultrasound detection of left ventricular ejection fraction (LVEF) and left ventricular short axis shortening rate (LVFS); right carotid artery cannulation to detect left ventricular systolic pressure (LVSP), The highest rate of left ventricular pressure increase (+dp/dtmax), the highest rate of left ventricular pressure decrease (-dp/dtmax); the kit detects serum and myocardial tissue malonaldehyde (MDA), superoxide dismutase (SOD) ), nitric oxide (NO), myeloperoxidase (MPO), tumor necrosis factor-ɑ (TNF-ɑ) and interleukin-6 (IL-6) levels; hematoxylin-eosin staining (HE) Staining to observe the morphological changes of myocardial tissue; terminal labeling (TUNEL) staining to observe the apoptosis of myocardial tissue; Western blotting to detect eNOS, B lymphoma-2 protein (Bcl-2) and Bcl-2 in myocardial tissue Related X protein (Bax) protein expression.

　　Results: Compared with the normal group, amputation 0.5h, amputation 0.75h heart rate increased, QT interval decreased, LVSP､+dp/dmax､-dp/dmax､LVEF､LVFS decreased, MPO､ MDA､TNF-ɑ､IL -6 increased, SOD decreased, cell arrangement was loose and necrotic, accompanied by a large number of inflammatory cell infiltration; myocardial cell apoptosis index increased, myocardial tissue Bcl-2 protein expression decreased, Bax protein expression increased, NO level ､eNOS The protein expression decreased in a time-dependent manner, and the difference was significant (P<0.05); compared with 0.75h amputation, heart rate decreased at 1.5h after amputation, QT interval and PR interval increased, LVSP､+dp/dmax､- dp/dmax, LVEF, LVFS increased, MPO, MDA, SOD, TNF-ɑ, IL-6 decreased, and the degree of myocardial pathological damage was reduced; myocardial cell apoptosis index decreased, Bcl-2 protein expression increased, Bax protein The expression decreased, the level of NO and the expression of eNOS protein increased, and the difference was significant (P<0.05).

　　Conclusion: The trauma of amputation surgery can cause ischemic ECG changes, impaired heart function and excessive oxidative stress and inflammatory damage in rats. The mechanism may be related to the inhibition of eNOS/NO pathway.