肺动脉高压幼犬肺动脉压力与肺动脉结构的关系

Relationship between pulmonary artery pressure and structure of pulmonary artery in puppies with pulmonary artery hypertension

目的 探讨肺动脉高压 (PH)时肺动脉压力 (PAP)与结构的关系。方法 实验幼犬 15条 ,分 2组 :分流组 (n =12 ) ,正常对照组 (n =3)。分流术后 90d两组行血流动力学检测后 ,放血处死 ,肺组织切片行病理学检测。结果 (1)分流组左下肺动脉压 (PLLPA)由 1.36kPa (1kPa=0 .75mmHg)升至11.13kPa,左下肺血管阻力 (LLPVR)由 5 .6 5Wood’s单位升至 14.31Wood’s单位 ,肺血流量 (PBF)由1.80L/min升至 5 .83L/min(P <0 .0 1) ,右肺动脉压 (PRPA)也有升高 ,但不及PLLPA显著。 (2 )分流犬左下肺动脉 (LLPA)出现平滑肌细胞 (SMC)显著增生并向肺动脉 (PA)远端延伸 ,肌性动脉 (MA)、部分肌性动脉 (PMA)数量增多 ,非肌性动脉 (NMA)数量减少 ,弹力、胶原纤维增多 ,血管中膜及内膜增厚 ,部分血管腔闭塞甚至出现血管丛样改变 ,分流犬右肺动脉 (RPA)仅出现轻度增生 ,且限于中膜。结论 PAP的升高可导致PA结构重塑 ,PH程度不同 ,所造成的PA病理改变也不同。而PA的病理改变又导致肺循环阻力的上升 ,从而导致PAP的进一步升高 ,形成恶性循环。

Objective\ To explore the relationship between pulmonary artery pressure (PAP) and structure of pulmonary artery (PA) in pulmonary hypertension (PH). Methods\ Fifteen experimental puppies were divided into 2 groups: shunted group ( n =12) and normal control group ( n =3). The pathologic examination of PA was done after hemodynamic changes were measured and recorded on the 90th day. Results\ (1) The pressure (PLLPA), resistance (LLPVR) and the blood glow (PBF) of the lower left pulmonary artery were elevated from 1.36 to 11.13 kPa (1 kPa=0.75 mm Hg), 5.65 to 14.31 Wood's U and 1.8 to 5.83 L/min , respectively ( P <0.01). The pressure of right pulmonary artery (PRPA) was also increased, but not so remarkable as PLLPA. (2) The structure of lower left pulmonary artery was changed observably, and the smooth muscle cells (SMC) proliferated and extended to the distance. The muscle artery (MA) and partially muscle artery (PMA) were increased in arterioles. The intima and media were proliferous and hypertrophic, and the occlusion and the plexiform were observed in some arterioles.However, the changes of right PA in shunt dogs were much milder than those of lower left PA and only observed in media. Conclusion\ The elevation of PAP resulted in the remodeling of PA. The different degrees of PH caused the different remodeling of PA, and the pathologic changes of PA led to a further elevation of PAP to form a vicious cycle.\;