AIM: Myocyte apoptosis in rats can be induced by acute ischemia, but time course and distribution of myocyte apoptosis were unclear.METHODS:DNA agarose gel electrophoresis and TdT-mediated dUTP nick end-labling(TUNEL) assay were performed to evaluate apoptosis in mycardium exposed to 45 minutes, 2 hours, 6 hours, 12 hours ischemia and sham-operated rats in vivo.RESULTS: DNA ladders were clearly visible in agarose gel of DNA from ischemic myocardium exposed to 2 hours, 6 hours and 12 hours ischemia, and DNA ladders became more apparent with increasing duration of ischemia. TUNEL positive cells with apoptotic morphologic characters were present in above ischemia time, and apoptotic index increased with increasing ischemia time. The majority of TUNEL positive cells were myocytes. Apoptotic index was higher in subendocardium than in subepicardium(P

Objective:To explore the differences in intravascular ultrasound results in elderly coronary heart disease(CHD)patients with different uric acid levels.Methods:A total of 145 elderly patients diagnosed with CHD in our hospital from December 2017 to May 2020 were included as study subjects.Uric acid levels were measured and intravascular ultrasound examination was conducted in all patients.They were divided into different groups based on uric acid levels: Group A(uric acid≤199 μmol/L), Group B(uric acid 200~399 μmol/L)and Group C(uric acid≥400 μmol/L). Data from intravascular ultrasound-derived indexes were analyzed and compared between the three groups.Results:There was no significant difference in the degree of left main stenosis between Group A and Group B, but it was less severe in both groups than in Group C( F=5.625, P=0.039). Plaque fibrous cap thickness showed no significant difference between Group B and Group C, but it was smaller than in Group A( F=7.825, P=0.020). Group C had the largest plaque area and maximum thickness among the three groups, followed by Group B[(11.12±1.73)mm 2 and(1.76±0.24)mm]and Group A[(8.29±3.14)mm 2 and(1.38±0.09)mm]( F=6.384 and 6.827, P=0.028 and 0.015). Conclusions:Elevated uric acid levels in elderly CHD patients can increase the area and thickness of plaques, and reduce plaque fibrous cap thickness, leading to an increased risk of formation of unstable plaques, which can be life-threatening for these patients.Thus, monitoring and managing uric acid levels should be stressed in elderly CHD patients.