Hoffmeister H M, Seipel L
Medical Hospital, Dept. III, University of Tübingen, FRG.
Basic Res Cardiol. 1992 Mar-Apr;87(2):161-72. doi: 10.1007/BF00801963.
Hemodynamic and metabolic effects of three times 4 min of oxygen deficiency were investigated in 18-month-old rats in comparison to 4-month-old Wistar rats. Left-ventricular isovolumic-pressure-generating capacity and dp/dtmax during isovolumic conditions and hemodynamic indices during intact circulation were determined in open-chest rats. Additionally, high-energy phosphates were measured at the end of the experiments after 20 min of postasphyxial recovery. Older rats had a significantly reduced isovolumic left-ventricular pressure generating capacity (236 +/- 9 vs 269 +/- 5 mm Hg; p less than 0.05) and a low cardiac index (55 +/- 9 vs 117 +/- 8 ml x min-1 x kg-1). The effects of the oxygen deficiency were comparable in both groups. The isovolumic pressure generating capacity was reduced for 11% vs 14%, and dp/dtmax for 13% vs 13%. The myocardial ATP-content was also decreased for the same extent in both groups (0.6 vs 1.0 mumol/gww). Both hemodynamic and biochemical results indicate that aged myocardium does not have a reduced tolerance to repeated periods of oxygen deficiency.
将18月龄大鼠与4月龄Wistar大鼠进行比较，研究了三次4分钟缺氧对血流动力学和代谢的影响。在开胸大鼠中测定了左心室等容压力产生能力以及等容状态下的dp/dtmax和完整循环期间的血流动力学指标。此外，在窒息后恢复20分钟的实验结束时测量了高能磷酸盐。老年大鼠的左心室等容压力产生能力显著降低（236±9 vs 269±5 mmHg；p<0.05），心脏指数较低（55±9 vs 117±8 ml·min-1·kg-1）。两组中缺氧的影响相当。等容压力产生能力降低了11%对14%，dp/dtmax降低了13%对13%。两组心肌ATP含量也在相同程度上降低（0.6对1.0 μmol/gww）。血流动力学和生化结果均表明，老年心肌对反复缺氧的耐受性并未降低。
