Lombardi D M, Reidy M A, Schwartz S M
Department of Pathology, University of Washington School of Medicine, Seattle 98195.
Am J Pathol. 1991 Feb;138(2):441-6.
While a number of studies have compared replication rates for vascular smooth muscle cells under different conditions, the absolute frequency of smooth muscle cell replication within the vessel wall has not been defined. This study reports a comparison of four parameters that might be expected to alter the accuracy of such counts. Neither autoradiograph exposure time, within specific time limits, nor dose of tritiated thymidine are major variables. Differences in absolute values obtained by autoradiography of enzyme-dispersed cells versus cells in cross-section, however, are reproducible. A comparison of frequency data from animals injected with tritiated thymidine during a 24-hour period compared with data from animals infused continuously for 1 week suggests that continuous infusion allows accumulation of labeled cells over time at a rate that is predictable from data of animals injected during 24 hours. In the current study it was found that although the frequency of tritiated thymidine-labeled thoracic aorta smooth muscle cells may vary according to the technique used in preparing the tissue, the daily rate of replication in a 4-month-old rat is estimated to be approximately 0.047% per day.
虽然已有多项研究比较了不同条件下血管平滑肌细胞的复制率，但血管壁内平滑肌细胞复制的绝对频率尚未明确。本研究报告了对四个可能会改变此类计数准确性的参数的比较。在特定时间限制内，放射自显影片曝光时间和氚标记胸腺嘧啶核苷剂量均不是主要变量。然而，酶分散细胞与横断面细胞的放射自显影所获得的绝对值差异是可重复的。对在24小时内注射氚标记胸腺嘧啶核苷的动物的频率数据与连续输注1周的动物的数据进行比较表明，连续输注可使标记细胞随时间积累，其速率可根据24小时内注射动物的数据预测。在本研究中发现，尽管根据制备组织所使用的技术，氚标记胸主动脉平滑肌细胞的频率可能会有所不同，但4月龄大鼠的每日复制率估计约为每天0.047%。
