双黄连对肺炎支原体感染大鼠组织中PDGF—BB影响的免疫组织化学研究

为探讨中药制剂双黄连粉针剂(双黄连)对反复肺炎支原体肺部感染大鼠肺组织中血小板衍生生长因子-BB(PDGF-BB)蛋白质水平表达的影响，给大鼠于24周内反复9次经超声雾化吸入肺炎支原体以复制其慢性肺部感染模型，并应用双黄连腹腔注射进行治疗干预；随后用PDGF-BB单克隆抗体按SABc法行免疫组织化学染色，定量图像分析。结果(1)感染组动物(n=4)支气管肺泡灌洗液肺炎支原体-PCR检测均为阳性，而对照组(n=4)和感染加双黄连治疗组(n=4)均为阴性(均为P<0．05)；三组动物的支气管和肺组织常规细菌培养结果均为阴性；感染组动物透射电镜检查见肺泡间隔增宽，其中有较多胶原纤维堆积，其余两组则未见明显异常。(2)感染组动物肺间质结缔组织中以及小气道和小血管的壁上可见较强的细颗粒状或细丝网状棕黄色PDGF-BB免疫组化染色阳性表达产物，其积分光密度为23．26±3．87(n=4)，显著高于正常对照组者(1．52±0．61，n=4，P<0．05)和感染加双黄连治疗组者(3．49±0．63，n=4，P<0．05)。提示双黄连可抑制反复肺炎支原体肺部感染大鼠肺组织中PDGF-BB蛋白质水平的表达，对于防止肺炎支原体肺部感染所引起的肺间质纤维化可能具有一定的作用。

The Immunohistochemical Research on the Effects of Shuanghuanglian on PDGF-BB Expression in Lung Tissue from Rats Infected with Mycoplasma Pneumoniae

In order to investigate the effects of Shuanghuanglian on the expression of platelet-derived growth factor-BB (PDGF-BB) in the lung tissue from rats repeatedly infected with mycoplasma pneumoniae (MP), the authors made a rat MP-infection model by infecting rats with MP for 9 times during a period of 24 weeks with a technique of ultrasonic nebulizing inhalation and treat ed the rats with Shuanghuanglian by peritoneal injection. Then immunohistochemical stain was performed with PDGF-BB mon oclone antibody and the results were quantitatively analyzed. The results showed that (1) MP polymerase chain reaction (PCR) tests indicated positive effectiveness in the bronchoalveolar lavage fluid (BALF) from all of the MP-infected rats (n= 4 ) while they were all negative in BALF from the control animals (n=4, P＜0. 05) and in BALF from those rats both infected with MP, and at the same time, treated with Shuanghuanglian (n= 4, P＜0.05). Bacterial cultures of the bronchial and lung tissue were negative in all three groups. The observation with transmission electron microscope found that the interalveolar septa were widened with increased amount of collagen in the MP-infected rats while there were no obvious abnormalities in the other two groups. (2) Strong positive stain of PDGF-BB protein was found in the interstitial connective tissue, the airway wall and the wall of blood vessels in the lung tissue from the MP-infected animals with the integral optical densities being 23. 26± 3.87 (n=4) which was significantly higher than the values of control group (1.52±0.61, n=4, P＜0.05) and of the group with MP-infection plus Shuanghuanglian treatment (3.49±0.63, n=4, P＜0.05). These results suggest that Shuanghuanlian can inhibit the overexpression of PDGF-BB in the lung tissue of rats with MP-infection,which may be helpful for the prevention and treatment of pulmonary interstitial fibrosis caused by the repeated MP-infection.