Smiljić Sonja, Radović Dragica, Miletić Milanka, Nestorović Vojkan, Trajković Goran, Savić Sladjana
Institute of Physiology, School of Medicine, Kosovska Mitrovica.
Srp Arh Celok Lek. 2010 Sep-Oct;138(9-10):577-83. doi: 10.2298/sarh1010577s.
Endocardial endothelium, a natural biological barrier between circulating blood in heart ventricle and cells, creates a complex yet finely tuned balance of interactions with the immediate environment.
We investigated the roles of theophylline, nonspecific phosphodiesterase inhibitor, and imidazole, an activator of phosphodiesterase on contractility of the right ventricle of rat heart, with intact and removed endocardial endothelium.
Adult rats, of both sexes, type Wistar albino, were used in this experiment. All experiments were conducted on the preparations of the right ventricle using two experimental models. In the first experimental model, an endocardial endothelium (EE) was preserved, and in the second model, an endocardial endothelium (-EE) was removed using 1% solution Triton X-100.
Theophylline (1 x 10(-2) mol/l) expressed the positive inotropic effect on the heart, regardless of the presence of the endocardial endothelium. Inotropic response as multiple process can be induced by inhibition of phosphodiesterase, accumulation of cyclic nucleotides and activation of Ca2+ channels. Imidazole (2 x 10(-3) mol/l) increased the contractility of the right ventricle of the heart with EE. The modulator effect of endocardial endothelium on contractility of imidazole proved to be significant. As imidazole influenced the contractility of the right ventricle only in the presence of the endocardial endothelium, it is assumed that its effect is mediated via deliverance of endothelial mediators with positive inotropic effect.
An intact endocardial endothelium is necessary for completion of contractile performance of the heart.
心内膜内皮是心室循环血液与细胞之间的天然生物屏障，它与周围环境形成了复杂而精细调节的相互作用平衡。
我们研究了非特异性磷酸二酯酶抑制剂茶碱和磷酸二酯酶激活剂咪唑对大鼠心脏右心室收缩性的作用，实验对象包括心内膜内皮完整和心内膜内皮去除的情况。
本实验使用成年Wistar白化大鼠，雌雄不限。所有实验均采用两种实验模型对右心室标本进行。在第一个实验模型中，保留心内膜内皮（EE）；在第二个模型中，使用1% Triton X - 100溶液去除心内膜内皮（-EE）。
无论心内膜内皮是否存在，茶碱（1×10⁻²mol/L）均对心脏表现出正性肌力作用。正性肌力反应作为一个多步骤过程，可由磷酸二酯酶抑制、环核苷酸积累和钙通道激活诱导产生。咪唑（2×10⁻³mol/L）增加了有EE的心脏右心室的收缩性。心内膜内皮对咪唑收缩性的调节作用被证明是显著的。由于咪唑仅在存在心内膜内皮时影响右心室的收缩性，推测其作用是通过释放具有正性肌力作用的内皮介质介导的。
完整的心内膜内皮对于心脏完成收缩功能是必要的。
