Leehey D J, Betzelos S, Daugirdas J T
J Lab Clin Med. 1987 Jun;109(6):687-91.
The extent of systemic arteriovenous shunting (arteriovenous anastomotic blood flow) was assessed in rats with experimental liver cirrhosis and control rats by injecting 15 micron microspheres into the left ventricle and measuring the percentage of injected spheres trapped in the pulmonary circulation. Cirrhotic rats with body temperature maintained at 38 degrees C were found to have increased trapping of microspheres in the pulmonary bed when compared with control rats studied under similar conditions (8.2% +/- 2.2% vs. 3.6% +/- 0.8%, P less than 0.05). The extent of arteriovenous shunting was also measured in control rats maintained at various body temperatures (34 degrees to 40 degrees C) with and without prior alpha-adrenergic blockade with phenoxybenzamine (0.1 mg/kg). Both body warming and alpha-adrenergic blockade independently increased the extent of arteriovenous shunting. In cirrhotic rats, body warming also increased shunting. However, in contrast to findings in control rats, alpha-adrenergic blockade did not further increase shunting in cirrhotic rats warmed to 40 degrees C. Moreover, the degree of shunting after combined body warming and alpha-adrenergic blockade was similar in cirrhotic and control rats. Our results indicate that increased peripheral arteriovenous shunting occurs in this model of experimental cirrhosis, and that the increased shunting may be related to altered physiologic regulation of arteriovenous anastomotic blood flow.
通过向左心室注射15微米的微球并测量滞留在肺循环中的注射微球百分比，评估实验性肝硬化大鼠和对照大鼠的全身动静脉分流程度（动静脉吻合血流量）。与在相似条件下研究的对照大鼠相比，体温维持在38摄氏度的肝硬化大鼠肺床中微球的滞留增加（8.2%±2.2%对3.6%±0.8%，P<0.05）。还在体温维持在不同水平（34摄氏度至40摄氏度）的对照大鼠中测量动静脉分流程度，这些大鼠在有无事先用酚苄明（0.1mg/kg）进行α-肾上腺素能阻滞的情况下进行。体温升高和α-肾上腺素能阻滞均独立增加动静脉分流程度。在肝硬化大鼠中，体温升高也增加分流。然而，与对照大鼠的结果相反，α-肾上腺素能阻滞并未进一步增加体温升至40摄氏度的肝硬化大鼠的分流。此外，体温升高和α-肾上腺素能阻滞联合作用后的分流程度在肝硬化大鼠和对照大鼠中相似。我们的结果表明，在这种实验性肝硬化模型中发生外周动静脉分流增加，并且分流增加可能与动静脉吻合血流量的生理调节改变有关。
