Lamont S V, Barritt G J
Cardiovasc Res. 1983 Feb;17(2):88-95. doi: 10.1093/cvr/17.2.88.
The effects of adrenaline on kinetically-distinct compartments of exchangeable calcium in the spontaneously-beating perfused rat heart were investigated under steady-state conditions using a 45Ca2+ outflow technique together with a nonlinear least-squares curve fitting procedure and 51Cr-EDTA to monitor the loss of freely-diffusible Ca2+ from the extracellular space. In addition to Ca2+ distributed in the vascular (compartment 1) and interstitial (compartment 2) spaces, the minimum number of kinetically-distinct compartments of cellular exchangeable Ca2+ (which include Ca2+ bound to extracellular sites on the sarcolemma) required to fit the data (compartments 3, 4 and 5) was three. A system in which cellular compartment 3 is linked to the vascular space and compartments 4 and 5 are linked to the interstitial space was consistent with the data. For hearts perfused under control conditions, the fractional transfer rates for Ca2+ outflow from cellular compartments 3, 4 and 5 were 0.70, 0.11 and 0.017 min-1, respectively. Adrenaline increased the quantity of exchangeable Ca2+ in compartment 5 and decreased that present in the compartment 4. Evidence that compartment 5 includes mitochondrial exchangeable Ca2+ is discussed. It is concluded that one of the actions of adrenaline on the heart is to increase the quantity of exchangeable Ca2+ in the mitochondria.
在稳态条件下，采用⁴⁵Ca²⁺流出技术、非线性最小二乘曲线拟合程序以及⁵¹Cr-EDTA来监测细胞外空间中自由扩散的Ca²⁺的流失，研究了肾上腺素对自发跳动的灌注大鼠心脏中动力学上不同的可交换钙池的影响。除了分布在血管（池1）和间质（池2）空间中的Ca²⁺外，拟合数据所需的细胞可交换钙（包括与肌膜上细胞外位点结合的Ca²⁺）的动力学上不同的最小池数（池3、4和5）为三个。细胞池3与血管空间相连且池4和5与间质空间相连的系统与数据一致。对于在对照条件下灌注的心脏，细胞池3、4和5中Ca²⁺流出的分数转移率分别为0.70、0.11和0.017 min⁻¹。肾上腺素增加了池5中可交换Ca²⁺的量并减少了池4中可交换Ca²⁺的量。讨论了池5包括线粒体可交换Ca²⁺的证据。得出的结论是，肾上腺素对心脏的作用之一是增加线粒体中可交换Ca²⁺的量。
