Changes in caval blood flow and right atrial pressure in response to catecholamines.

The type and magnitude of changes in blood flow in the anterior (cranial) and posterior (caudal) caval veins and shifts in the mean right atrial pressure induced by catecholamines (epinephrine and norepinephrine) were studied in acute experiments on cats. It was found that irrespective of right atrial pressure shifts, the increase in the blood flow in the anterior vena cava was more pronounced than in the posterior vena cava and was determined by blood redistribution due to more pronounced increase in vascular resistance in the abdominal aorta basin.