Promotion of normal healing of bone defects under estrogen deficiency by implantation of beta‐tricalcium phosphate composed of rod‐shaped particles

We compared the healing of bone defects in ovariectomized rats implanted with beta‐tricalcium phosphate (β‐TCP) composed of rod‐shaped particles, which were prepared using the applied hydrothermal method (HTCP), and that of bone defects implanted with conventional β‐TCP composed of globular‐shaped particles (CTCP), which were prepared by normal sintering. Eight‐week‐old female Wistar rats were ovariectomized, and 2 weeks after the operation, 0.5‐ to 0.6‐mm diameter spherical granules of each ceramic were implanted in a bone defect created in the distal end of the femur. Four, 8, and 12 weeks after implantation, the amount of newly formed bone implanted with HTCP was significantly larger than that implanted with CTCP and was equivalent to that in non‐ovariectomized sham‐operated rats. Without implantation, spontaneous repair of the trabecular bone was barely observed. The physiological structure of the trabecular network was maintained in the region implanted with HTCP, but that in the region implanted with CTCP was severely destroyed. Gene expression microarray analysis revealed that the expression of genes involved in interferon signaling pathways was upregulated in osteoclasts cultured on HTCP compared with that cultured on CTCP. Our results suggest that the microstructure of β‐TCP affected the biological behavior of osteoclasts and regulated local bone metabolism. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:189–196, 2014.     

Endothelial and neuronal nitric oxide synthases variably modulate the oestrogen‐mediated control of blood pressure and cardiovascular autonomic control

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去势大鼠骨质疏松性骨小梁的压缩断裂仿真

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Ovariectomy Aggravated Sodium Induced Hypertension Associated With Altered Platelet Intracellular Ca in Dahl Rats

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雷洛昔芬对去卵巢大鼠血脂的影响

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淫羊藿总黄酮对去势大鼠骨密度的影响

目的:探讨淫羊藿总黄酮对去势大鼠骨密度的影响。方法:取10月龄雌性SD大鼠60只,随机分为正常组、模型组、雌激素组和淫羊藿低、中、高剂量组,每组10只。除正常组外,其余各组大鼠均行双侧卵巢切除术,术后1周分别给予生理盐水、淫羊藿总黄酮和雌激素进行干预,共90天,观察各组大鼠全身、股骨及腰椎骨密度的变化。结果:正常组和雌激素组大鼠全身骨密度均显著高于其他各组(P均0.05);淫羊藿总黄酮低、中、高剂量组大鼠全身骨密度与模型组比较,差异无统计学意义(P0.05);淫羊藿总黄酮低、中、高剂量组大鼠股骨骨密度显著高于模型组(P0.05),淫羊藿总黄酮中、高剂量组大鼠腰椎骨密度显著高于模型组(P0.05)。结论:淫羊藿总黄酮能明显抑制去势大鼠股骨及腰椎骨密度的降低,对去势大鼠全身骨密度无明显影响。