[The sympathetic-adrenal system in experimental massive pulmonary embolism].

The density of adrenergic nervous plexus in ventricular myocardium, the concentration of catecholamines in blood and in adrenal medulla were studied on 24 dogs with acute massive pulmonary embolism (MPE) and also on 13 control dogs. Moderate and shortterm activation of adrenal system took place in control group. During the first hour of MPE the activation of both adrenal and mediator systems was revealed. To the six hour of MPE the enlarged activity of adrenal chromaffin cells was maintained, but the density of adrenergic nervous plexus in ventricular myocardium decreased. In cases, when MPE was followed by heart failure, a quick and significant decrease of mediator concentration in myocardium and increase of adrenal medullary cells activity took place. Thus, the velocity of revealed changes may be the reason of transition processes exit to compensative or decompensative state.