Production of experimental toxemia in the pregnant rabbit.

Experimental toxemia of pregnancy was induced in 51 of 122 rabbits by constriction of the aorta below the renal arteries. The approach was extraperitoneal and dependent on the accuracy in calibrating this stricture between 0.6 and 1.0 mm. Experimental toxemia in the rabbit was characterized by hypertension, proteinuria, weight gain, and reduced weight of the fetus. Blood pressure and blood flow studies distal to the aortic constriction demonstrated a marked diminution of blood supply below the constriction. The light microscopic changes in the kidneys and in the liver were similar to those of human toxemia. The electron microscopic changes consisted of endothelial swelling and subendothelial deposits. In a separate experiment, 22 pregnant rabbits near term had an aortic constriction varying between 0.6 and 1.0 mm. This constriction lasted 4 to 12 days. Glomerular deposits of fibrinogen were demonstrated by immunofluorescence in 20 of 22 animals. The intensity of the immunofluorescence was related to the severity and duration of the aortic stricture.