[Changes of hemodynamics and concentrations of nitric oxide, endothelin, prostacyclin, and thromboxane A2 during portal cavity clamping and opening in portal hypertensive canines].
OBJECTIVE
To observe the changes in systemic hemodynamics and their relations to the concentrations of nitric oxide, endothelin, prostacyclin, and thromboxane A2 after portal cavity clamping and opening in portal hypertensive canines.


METHODS
Twelve canines were randomly divided into control group and model group, and partial ligation of the portal vein was performed in the model group. Portal cavity clamping and opening was performed 12 weeks later in the two groups. The hemodynamic parameters including cardiac output index (CI), heart rate (HR), mean artery blood pressure (MABP), central venous pressure (CVP), pulmonary arteriole wedge pressure (PAWP), and systemic vascular resistance index (SVRI) were measured during the operation. Samples were obtained from the central vein at 3 time points during the operation for measuring NO, ET, PGI2, and TXA2.


RESULTS
Portal vein ligation and portal cavity clamping produced obvious changes in the systemic circulation of the dogs, and the alteration was milder in the control group. After obstruction of the portal vein, the NO levels in systemic circulation in portal hypertensive dogs declined obviously, but gradually recovered the normal level after reperfusion.


CONCLUSIONS
Systemic circulation undergoes significant alterations after portal vein obstruction, but its changes in portal hypertensive dogs are milder than those in the control group, the mechanism of which needs further investigation.
Chi
Xin-Jin
XJ
Department of Anesthesiology, Third Affiliated Hospital, SUN Yat-sen University, Guangzhou 510630, China. chixinjin@yahoo.com.cn
Wei
Jian-Qi
JQ
Hei
Zi-Qing
ZQ
Ge
Mian
M
Liu
De-Zhao
DZ
D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D016232:Endothelins / Q000097:blood*; D011464:Epoprostenol / Q000097:blood*; D006439:Hemodynamics; D006975:Hypertension, Portal / Q000097:blood* / Q000503:physiopathology*; D009569:Nitric Oxide / Q000097:blood*; D010949:Plasma / Q000378:metabolism; D011169:Portal Vein / Q000503:physiopathology; D013928:Thromboxane A2 / Q000097:blood*; D014682:Vena Cava, Inferior / Q000503:physiopathology
D016232:Endothelins; D009569:Nitric Oxide; D013928:Thromboxane A2; D011464:Epoprostenol