| Abstract: | The character and values of changes of the pulmonary hemodynamics and venous return following acetylcholine, histamine and isoproterenol intravenous injection were studied in acute experiments on the anesthetized cats. After depressor drugs injection the character and values of changes of pulmonary artery pressure and flow were different. In 67% cases the pulmonary artery pressure was decreased, and in 33%--it was elevated, meanwhile the pulmonary artery flow was decreased in 48% cases and it was increased in 52%, i.e., in the equal number of observations. Thus, following depressor drugs intravenous injection, hemodynamic mechanisms of the changes of pulmonary artery pressure and flow are different. The character and values of changes of the pulmonary artery pressure are correlated with the changes of pulmonary vascular resistance and are not dependent with the left atrial pressure shifts. The changes of the pulmonary artery blood flow are caused by the changes of the venous return and are not correlated with the changes of the right and left atrial pressure. |
