OBJECTIVE: To investigate the relationship between changes in cardiac electrophysiology and cardiac function and endothelial nitric oxide synthase/nitric oxide (eNOS/NO) pathway in rats after amputation
Method: Establishment of a trauma model of the left hind limb. Use electrocardiogram (ECG) to divide rats into normal groups (anaesthetic only), cut control group, cut 0.25h, cut 0.5h, cut 0.75h, cut 1.5h, 12 rats, rat heart rate, QT detection interval? Changes in PR interval; ultrasound detection of left ventricular ejection rate (LVEF)? Left ventricular short axis shortening rate (LVFS); insert the right carotid artery cannula to detect left ventricular systolic pressure (LVSP)? What is the maximum rate of increase in left ventricular pressure (+ dp/dtmax)? Maximum reduction rate of left ventricular pressure (-dp/dtmax); can this kit detect malondialdehyde (MDA) in serum and myocardial tissue? Superoxide dismutase (SOD)? Nitric oxide (NO)? Myeloperoxidase (MPO)? Tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels; hematoxylin-eosin staining (HE) is used to observe the morphological changes of myocardial tissue; the end is used to observe the apoptosis markers of myocardial tissue (TUNEL) staining; Western blotting to detect eNOS expression? B lymphoma 2 protein (Bcl-2)? Results: Bcl-2 related X protein (Bax) protein in myocardial tissue
Result: Compared with the normal group, did the heart rate increase at 0.5 hours and 0.75 hours after cleavage? QT interval is reduced, LVSP? + dp/dmax? -dp/dmax? LVEF? Is LVFS down? MDA? TNF--? IL-6 increased, SOD decreased, cell loosening and necrosis decreased, accompanied by a large number of inflammatory cell infiltration; myocardial cell apoptosis index increased, myocardial tissue Bcl-2 protein expression decreased? The expression of Bax protein increased with time, while the expression of NO eNOS protein decreased with time, the difference was statistically significant (P\u003c0.05). Compared with 0.75 hours, the heart rate of 1.5 hours decreases, QT interval and PR interval increase, LVSP + dp/dmax? -dp/dmax? LVEF? LVFS has increased, is MPO? MDA? turf? Decreased TNF-αIL-6, decreased myocardial pathological damage, decreased myocardial cell apoptosis index, increased Bcl-2 protein expression, decreased Bax protein expression, and NO level? The expression of eNOS protein increases, is the difference statistically significant (P\u003c0.05)?
Conclusion: Will amputation trauma cause ischemic ECG changes, cardiac dysfunction and excessive oxidative stress in rats? Is inflammatory injury and its mechanism related to the inhibition of eNOS/NO pathway?