Analyses of monocrotaline-induced rabbit model of chronic pulmonary hypertension

AIM:To explore the feasibility of a rabbit model with chronic monocrotaline (MCT)-induced pulmonary hypertension. METHODS: Eighty-four New Zealand rabbits were randomly divided into two groups: control group of 24 rabbits and MCT group of 60 rabbits. The rats in both groups were given the same diet and were raised under the same conditions. Chronic pulmonary hypertension in the MCT group was developed by injection of MCT solution into the abdominal cavity, whereas only the same dosage of the mixed pure ethanol and physiologic saline was injected into the abdominal cavity in the control group. The pulmonary artery systolic pressure was detected by pressure-guided microcatheter into the pulmonary artery 28 days after injection. RESULTS: The results of the right heart catheterization showed that, except for the right atrial diastolic pressure, the pressures of the heart chambers in the MCT group were not significantly different from those in the control group. The average pulmonary artery systolic pressure in the MCT group failed to reach 30 mmHg, and the models were thus not successful. Pathology results showed that the pulmonary artery wall in the MCT group thickened and the smooth muscle tissue significantly proliferated. CONCLUSION: MCT injection can thicken the pulmonary artery smooth muscle in rabbits, suggesting some hemodynamic changes. Increase of pulmonary arterial pressure in rabbits is not stable, necessitating further study in this animal model.