Urinary 3H-tetracycline and pyridinium crosslinks differ in their response to calcium restriction in mature and aged rats.
Urinary 3H-tetracycline and pyridinium crosslinks differ in their response to calcium restriction in mature and aged rats.
复制标题
成熟和老年大鼠中尿 3H-四环素和吡啶交联对钙限制的反应不同。
DOI：
10.1007/s002239900631
复制
发表时间：
1999
影响因子：
4.2
通讯作者：
Shapses,SA
中科院分区：
文献类型：
--
作者：
Talbott,SM;Chowdhury,H;Shapses,SA
The aim of this study was to evaluate bone resorption (BR) in rats by two methods: chronic3H-tetracycline labeling (3HTC) and pyridinium crosslink excretion (PYDX), and compare the sensitivity of these markers in two age groups. Female Sprague-Dawley rats at 12–29 weeks of age (``mature'', n = 12) and at 40–57 weeks of age (``aged'', n = 22) were examined. Skeletal incorporation of3HTC in aged rats was 43 ± 8% of that in mature animals (P< 0.01), indicating an age-related decrease in bone turnover. BR was modulated over 9 weeks by calcium restriction (CR), measured by urinary excretion of both3HTC and PYDX, and compared with age-matched, calcium-adequate controls. At baseline, urinary excretion of3HTC was not significantly different between age groups, whereas urinary PYDX was 14–20% higher in mature compared with aged rats (P< 0.01). CR produced a 32–39% peak increase in BR (P< 0.01) compared with controls that did not differ significantly between marker or age group. Urinary3HTC was elevated at weeks 1–3 (P< 0.01) and reached maximal values at week 2 (32 ± 17%). Urinary PYDX, however, was not elevated until week 2, reached maximal levels at week 3 (39 ± 15%), and remained elevated until week 6 (P< 0.01). These data indicate that although both markers are elevated by CR, marker response differs with age, and variability exists for acute and chronic responses.
