OBJECTIVES Metoprolol is a cardioselective competitive beta-1 adrenergic receptor antagonist with antihypertensive properties, devoid of intrinsic sympathomimetic activity. Various studies have suggested the effect of beta-blockers on bone remodeling. We aimed to investigate whether metoprolol affects bone remodeling by altering anti-inflammatory and pro-inflammatory cytokines. MATERIALS AND METHODS Surgical defects of 3 mm diameter were created in tibiae of 72 Sprague-Dawley rats. Rats were randomly assigned to a control group without metoprolol treatment (n = 36), and a test group treated with 0.1 mg/kg/day metoprolol (n = 36). Six rats from each group were sacrificed at days 0, 1, 3, 5, 7, and 14. The percentages of cells, which showed positive immunohistochemical staining for IL-1β, IL-6, IL-10, and RANKL, were assessed in the defect area. Differences in percentages of stained cells within each of the test and control groups over various time intervals were tested using one-way ANOVA test. A P value of < 0.05 was considered statistically significant. RESULTS No significant differences in IL-1β, IL-10, IL-6, and RANKL expressions were found between test and control groups at the same interval. Significant reduction was observed at different time intervals in the same group (P < 0.05). CONCLUSION Metoprolol did not reduce bone-active cytokine: IL-1β, IL-6, and RANKL. It also did not elevate IL-10 expression levels. Thus, it does not appear to decrease osteoclastogenesis. CLINICAL RELEVANCE Results from this animal model help us understand any effect of metoprolol on bone healing by potential contribution to different real-world clinical research.

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腹膜内给予美托洛尔对大鼠胫骨骨缺损愈合的影响：一项先导研究。

目的美托洛尔是一种具有抗高血压性质的心脏选择性竞争性β-1肾上腺素能受体拮抗剂，没有内在的拟交感神经活性。各种研究表明，β-受体阻滞剂对骨骼重塑的作用。我们旨在研究美托洛尔是否通过改变抗炎和促炎细胞因子来影响骨骼重塑。材料与方法在72只​​Sprague-Dawley大鼠的胫骨中产生了3 mm直径的手术缺损。将大鼠随机分为未接受美托洛尔治疗的对照组（n = 36），以及接受0.1 mg / kg /天美托洛尔治疗的测试组（n = 36）。在第0、1、3、5、7和14天处死每组六只大鼠。评估显示IL-1β，IL-6，IL-10和RANKL阳性免疫组化染色的细胞百分比在缺陷区域。使用单向方差分析测试在不同时间间隔内每个测试组和对照组中染色细胞的百分比差异。AP值<0.05被认为具有统计学意义。结果在相同时间间隔的测试组和对照组之间，IL-1β，IL-10，IL-6和RANKL表达没有显着差异。同一组在不同时间间隔观察到显着减少（P <0.05）。结论美托洛尔未降低骨活性细胞因子：IL-1β，IL-6和RANKL。它也没有升高IL-10表达水平。因此，它似乎没有减少破骨细胞生成。临床相关性该动物模型的结果通过对不同现实世界临床研究的潜在贡献，帮助我们了解美托洛尔对骨骼愈合的任何影响。