急性心肌梗死对猪骨代谢的影响及潜在机制

The Influence and Potential Mechanism of Acute Myocardial Infarction on Bone Metabolism in Pigs

摘要: 目的：本研究旨在探究急性心肌梗死(AMI)对猪骨代谢的影响及潜在机制。方法：本研究用12头8周龄雄性约克夏猪作为实验动物，随机分为手术组(n = 6)及假手术组(n = 6)。手术组猪使用左前降支动脉结扎法建立心肌梗死模型，假手术组进行相同的手术，但未结扎左前降支。(1) 测量并比较两组猪的基线数据；(2) 两组猪术前及术后30 d LVEF的检测、白细胞分析、血清钙、磷及PTH水平的及骨代谢指标检测；(3) 双能X射线吸收法测定两组实验猪术后30 d腰椎(L1~L4)及左股骨骨密度。(4) 对两组猪于术后30 d取右股骨进行H&E染色，显微镜下观察并比较两组实验猪骨小梁面积。结果：1) 两组猪基线数据比较均无统计学差异(P > 0.05)。2) 手术前，两组LVEF值无显著差异(P > 0.05)；手术后，与假手术组相比较，手术组的LVEF值显著下降(P < 0.05)。3) ① 术前和术后，两组猪淋巴细胞、中性粒细胞计数和百分比及单核细胞百分比均无统计学差异(P > 0.05)。② 手术前两组单核细胞计数无显著差异(P > 0.05)；手术后30 d手术组单核细胞计数显著升高(P < 0.05)。4) ① 手术前，两组猪血钙、血磷无显著差异(P > 0.05)；与假手术组相比，术后30 d手术组血钙、血磷水平显著下降(P < 0.05)。② 手术前，假手术组与手术组的甲状旁腺素水平比较无显著差异(P > 0.05)；手术组在术后30 d的甲状旁腺素水平显著高于假手术组(P < 0.05)。5) 手术前，假手术组与手术组的25-(OH)D、骨钙素N端中分子片段水平无显著差异(P > 0.05)；手术组在术后30 d的25-(OH)D、骨钙素N端中分子片段水平显著低于假手术组(P < 0.05)。6) 术后30 d，手术组腰椎及左股骨骨密度显著低于假手术组(P < 0.05)。7) 显微镜下观察，同等放大倍数单个视野中手术组右股骨骨小梁面积小于假手术组。结论：本研究显示心肌梗死可导致猪全身骨吸收标志物增加，从而骨量减低，骨密度下降。

Abstract: Objective: The purpose of this study is to investigate the effects of acute myocardial infarction (AMI) on bone metabolism in pigs and its potential mechanisms. Methods: This study used 12 8-week-old male Yorkshire pigs as experimental animals, divided into surgical group (n = 6) and sham surgery group (n = 6). The surgical group of pigs was subjected to a left anterior descending artery ligation method to a myocardial infarction model, and the sham surgery group underwent the same surgery but did not ligate the left anterior descending branch. (1) The baseline data in the two groups of pigs were measured and compared; (2) The detection of LVEF of the two groups of pigs before and after 30 days of surgery, white blood cell analysis, levels of serum, phosphorus and PTH, and detec-tion of bone metabolism indicators; (3) The bone mineral density of the lum spine (L1~L4) and left femur of the two groups of experimental pigs was measured by dual-energy X-ray absorptiometry 30 days surgery. (4) The right femur of the two groups of pigs was taken for H&E staining on post-operative day 30, and the trabecular of the two groups of experimental pigs was observed and compared under the microscope. Results: 1) There was no statistically significant difference in the baseline data size of the two groups of (P > 0.05). 2) There was no significant difference in the LVEF value size of the two groups before surgery (P > 0.05); the LVEF value size of the surgical group was significantly lower than that of the sham surgery group after surgery (P < 0.05). 3) ① Pre- and post-operation, no statistically significant differences were observed in lymphocyte count, neutro-phil count (and percentages), or monocyte percentage between the two groups (P > 0.05). ② Pre-operatively, monocyte counts showed no significant difference between groups (P > 0.05); the mon-ocyte count of the two groups was significantly higher after 30 days of surgery and was statistically significant (P < 0.05). 4) ① There was no significant difference in the blood calcium and blood phosph size of the two groups of pigs before surgery (P > 0.05); the blood calcium and blood phos-phorus size of the surgical group was significantly lower than that the sham surgery group after surgery (P < 0.05). ② There was no significant difference in the parathyroid hormone levels be-tween the sham group and the surgical group before surgery (P > 0.05); the parathyroid hormone levels of the surgical group were significantly higher than those of the sham surgery at 30 days after surgery (P < 0.05). 5) There was no significant difference in the of 25-(OH)D and N-terminal mid-molecular fragment of osteocalcin between the sham surgery group and the surgical group be-fore surgery (P > 0.05); the levels of 25-(OH)D and N-terminal mid-molecular fragment of osteocal-cin in the surgical group were significantly lower than of the sham surgery group at 30 days after surgery (P < 0.05). 6) At 30 days surgery, the bone mineral density of the lumbar spine and left fe-mur in the surgical group was significantly lower than that in the sham operation group (P < 0.05). 7) Under the microscope, the trabecular area of the right femur in the surgical group was smaller than that in the sham surgery group in a single field of. Conclusion: This study shows that myocar-dial infarction can lead to an increase in the overall bone resorption markers in pigs, resulting in a decrease in bone mass and bone density.