老年性骨质疏松模型小鼠的颅骨增龄性变化

Age-related Changes of Calvarial Bone in Senile Osteoporotic Mouse Model

为对比观察快速衰老型小鼠(SAMP6)与正常老化型小鼠(SAMR1)颅骨的增龄性变化,本试验采用活体micro-CT扫描定量观察SAMP6和SAMR1小鼠24、30、36周龄时的颅骨骨体积密度(BV/TV)。小鼠36周龄完成micro-CT扫描后,解剖颅骨,HE染色和抗酒石酸酸性磷酸酶(TRAP)染色对比观察小鼠颅骨组织学特点并测量破骨细胞数目。结果显示,不同年龄SAMP6的颅骨BV/TV值均显著低于同龄SAMR1;随年龄增长,SAMP6颅骨BV/TV显著降低,而SAMR1颅骨BV/TV无显著变化;与SAMR1相比,SAMP6颅骨内外骨板更薄,板障更宽;板障内破骨细胞更多,且差异显著。本试验表明随年龄增长,SAMP6的颅骨骨体积密度降低,且均小于同龄SAMR1,而SAMR1的无显著变化。

To compare the age-related changes of calvarial bone in senescence-prone inbred mouse strains（SAMP6）and the normal control senescence-resistant inbred mouse strains（SAMR1）,in vivo micro-CT scanning was performed for the bone volume density（BV/TV）of cranium in these two strains at their 24-week-old,30-week-old and 36-week-old,respectively.Directly after the last scanning of micro-CT,the calvarial specimens were dissected and subjected to HE staining and tartrate-resistant acid phosphatase（TRAP）staining for histological observation and osteoclasts count.The results showed that the BV/TV of cranium in SAMP6 were significantly lower than that of the age-matched SAMR1 at three time points.BV/TV of cranium in SAMP6 decreased significantly with aging while no significant changes in SAMR1.Compared with SAMR1,the internal and external amella of cranium were thinner in SAMP6,and the number of osteoclasts was greater in the diploof SAMP6 as well.This study suggested that the bone volume density of cranium in SAMP6 decreased with aging and was lower than that of the age-matched SAMR1,while no significant changes in SAMR1.