Increased pressor activity in incubated plasma of pregnant rabbits

A study to measure the pressor activity which is generated in incubated plasma of pregnant and nonpregnant rabbits was performed by means of a recently modified bioassay technique. It was found that plasma of normal pregnant rabbits generated significantly higher amounts of active pressor principle (APP) than those generated by plasma of nonpregnant rabbits. The possible relevance of these results to blood pressure regulation during normal and abnormal pregnancies is discussed.