Hemodynamic state and the role of angiotensin II in ovarian hyperstimulation syndrome in the rabbit.

OBJECTIVE

To investigate the hemodynamic state in the ovarian hyperstimulation syndrome (OHSS) in the rabbit model and to determine the role of angiotensin II in the pathophysiology of this syndrome.

DESIGN

Experimental study.

SETTING

Physiology laboratory.

ANIMAL(S): Female New Zealand rabbits were studied; 16 rabbits were stimulated with gonadotropins, and 6 were controls. Six of the stimulated rabbits received additional treatment with captopril.

MAIN OUTCOME MEASURE(S): Cardiac index, blood pressure, and heart rate were recorded.

RESULT(S): Gonadotropin-stimulated rabbits had significant enlargement of ovaries that was not modified by captopril. Ascites was present in 80% of animals in the OHSS group; captopril significantly decreased the incidence and volume of ascites. The three groups did not differ in blood pressure, heart rate, cardiac index, and total peripheral resistance.

CONCLUSION(S): In rabbits with OHSS, ascites are a primary event. Such animals are normotensive and have normal vascular resistance and cardiac index. Angiotensin-converting enzyme inhibition decreases the incidence of OHSS in the rabbit model by 30%, suggesting that angiotensin II may play a role in the formation of ascites.