观察抗原攻击的哮喘大鼠肺组织和大脑皮层的LTB4含量及其合成酶mRNA表达量的变化。方法：用卵白蛋白致敏大鼠, 抗原攻击后，用反向高效液相法（RP2HPLC）测定肺组织和大脑皮层匀浆的LTB4含量。用半定量RT2PCR法检测LTA4水解酶mRNA的表达量。结果：哮喘大鼠肺组织和大脑皮层匀浆中的LTB4含量显著高于正常对照组, 其LTA4水解酶mRNA 的表达也明显提高。地塞米松（DXM, 0.5mgökg, ip）可以减少LTB4含量的增加，抑制LTA4水解酶mRNA的表达。结论：哮喘大鼠肺组织和大脑皮层的LTB4含量及其合成酶的mR2NA的表达同步增高，提示哮喘时中枢神经系统对肺组织可能有神经免疫调节作用。

本研究目的旨在观察PDE IV 抑制剂咯利普兰对沙丁胺醇（SB）耐受性的影响。用豚鼠离体气管标本，预先接触SB1μmol•L-1，1h可使SB对抗乙酰甲胆碱气管收缩作用的剂量反应曲线右移5倍，最大松弛率下降30%，形成SB气管松弛作用的耐受性。磷酸二酯酶（PDE）IV抑制剂咯利普兰能翻转SB气管松弛作用的耐受性，但PDE Ⅲ抑制剂氰胍哒嗪则不能。虽然蛋白合成抑制剂环己酰亚胺对SB耐受性无预防作用，但上述结果仍提示SB气管松弛作用的耐受性可能与PDEIV活性的增高有关。

观察第二代磷酸二酯酶4（PDE4）选择性抑制剂吡拉米特（piclam ilast）和西拉米特（ciclam ilast）对离体气管平滑肌的支气管扩张作用和抗变态反应作用, 比较它们的作用强度。方法: 采用离体豚鼠气管片, 蓄积剂量法评价piclam ilast 和ciclami last对平滑肌静息张力和氨甲酰胆碱（CCh）所致高张力的松弛作用，以及它们对异丙肾上腺素（ISO）的协同作用；用生物检定法评价两者对致敏豚鼠肺组织抗原攻击释放过敏性慢反应物质（SRS-A）的抑制作用；以及用Schultz-Dale法评价两者对致敏豚鼠气管片抗原攻击所致收缩的抑制作用。结果：piclami-last和ciclami last对静息张力气管平滑肌均有直接松弛作用, EC50分别为： piclam ilast 1100×10-5 mol/L, ciclami-last 0184×10-5mol/L；对CCh所致收缩无明显松弛作用，但都能协同ISO的舒张作用，并能有效减少抗原攻击致敏豚鼠肺组织SRS-A释放量，明显抑制致敏豚鼠气管Schultz-Dale反应。结论：结果显示，虽然piclam ilast 和cic-lamilast的支气管扩张作用强度相同，但ciclam ilast抗变态反应性作用明显强于piclam ilast。

The aim of this study was to investigate whether transforming growth factor-h1 (TGF-h1) could induce alveolar epithelial to mesenchymal transition (EMT) in vitro. Alveolar epithelial cells (AECs) from SD rats were isolated by elastase cell dispersion and IgG panning. Expression of a-smooth muscle actin (a-SMA) was assayed using Western blotting and immunostaining analysis. Morphological changes, the markers of epithelial cell (E-cadherin), and stress fiber by actin reorganization were detected by an indirect immunostaining. The contents of collagen I were determined by spectrophotometry. The levels of endogenous TGF-h1 were measured with ELISA. Incubation of AECs with TGF-h1 (0.1～10ng/mL) induced abundant expression of a-SMA protein, and a-SMA expression in AECs reached a plateau when TGF-h1 was N 3ng/mL. Furthermore, we found that TGF-h1 (3ng/mL) exposure of AECs induced an authentic EMT characterized by abundant expression of a-smooth muscle actin, transformation of myofibroblastic morphology, increased formation of stress fiber by actin reorganization, and loss of epithelial marker E-cadherin. Meanwhile, significant increase in the levels of collagen I from 32.0 F 6.6mg/g in control to 98 F 10.8mg/g in TGF-h1-treated group was found over a 72h incubation period. Moreover, following stimulated by TGF-h1 (3ng/mL), a marked and time-dependent increase in endogenous TGF-h1 released from AECs was observed. At time points 72h, TGFh1 release mounted to 3451pg/ml, which was much enough to induce EMT in vitro. These results demonstrated that AECs, under stimulation of TGF-h1, underwent a conversion process into myofibroblasts in vitro.

human PDE4A was improved by ammonium sulfate fractionation, DEAE Sephadex A-50 chromatography, and Sephadex G-100 chromatography. The activity of PDE4A was measured by high performance liquid chromatography (HPLC). RESULTS: Induced PDE4A activity expressed in crude yeast cell GL62 supernatant and pellet was (340±21) nmol•g-1•min-1 and (250±25) nmol•g-1•min-1 respectively. The specific activity of recombinant PDE4A in supernatant was improved 6.4 fold. Ciclamilast, piclamilast, and rolipram could inhibit PDE4A activity. The IC50 values (95% confidence limits) of ciclamilast, piclamilast, and rolipram were 1.27 (0.84-1.91), 66.4 (33.3-132.2), and 3.73 (2.51-5.53) μmol/L respectively. Zaprinast, aspirin, and indomethacin had no obvious inhibitory effect on PDE4A activity. CONCLUSION: The specific activity of PDE4A expressed in yeast cell GL62 can be improved by ammonium sulfate fractionation, DEAE Sephadex A-50 chromatography, and Sephadex G-100 chromatography. Ciclamilast, piclamilast, and rolipram can inhibit PDE4A activity while zaprinast, aspirin, and indomethacin have no obvious inhibitory effect on PDE4A activity. Human PDE4A expressed in GL62 might be useful in the research and screening of new selective PDE4 inhibitors.