[The change of mast cells and macrophages in the lung of rat with pulmonary hypertension].

Objective: To investigate the change of mast cells and macrophages in lung tissue of rats with pulmonary hypertension (PH) and the effect of simvastatin on it.

Methods: Pulmonary hypertension was established as follow, a shunt between abdominal aorta and inferior vena cava was created in rats, 8 days later, the rats were injected with monocrotaline (60 mg/kg). Moreover, a subgroup of rats were given simvastatin 2 mg/ (kg x d). The mean pulmonary artery pressure (mPAP) and right ventricular weight were measured, and the ratio of right ventricle/left ventricle plus septum CRV/(LV+S)) was calculated. The LSAB method was used to stain anti-tryptase and ED1 in the lung tissue of the rats.

Results: In comparision with the control group, mPAP and RV/ (LV+S) of PH rats increased significantly (P<0.05). The RV/(LV+S) in simvastatin group was lower than that in PH rats (P<0.05). The amount of mast cells and macrophages in PH rats were more than that in control group (P<0.05). The amount of mast cells in simvastatin intervention group decreased in comparision with the PH group while the macrophages showed no difference in simvastatin group (P>0.05).

Conclusion: Mast cells and macrophages may be involved in the development of PH and/or the lesion caused by PH accelerate the accumulation and activation of mast cell and macrophages. Simvastatin has a preventive effect on rat PH, it inhibits mast cell proliferation may be one of mechanism.