Akhter S R, Ikezaki H, Gao X P, Rubinstein I
Department of Medicine, University of Illinois at Chicago, and West Side Department of Veterans Affairs Medical Center, Chicago, Illinois 60612, USA.
J Appl Physiol (1985). 1999 May;86(5):1603-9. doi: 10.1152/jappl.1999.86.5.1603.
The purpose of this study was to determine whether dexamethasone attenuates grain sorghum dust extract-induced increase in macromolecular efflux from the in situ hamster cheek pouch and, if so, whether this response is specific. By using intravital microscopy, we found that an aqueous extract of grain sorghum dust elicited significant, concentration-dependent leaky site formation and increase in clearance of FITC-labeled dextran (FITC-dextran; mol mass, 70 kDa) from the in situ hamster cheek pouch (P < 0.05). This response was significantly attenuated by dexamethasone (10 mg/kg iv). Dexamethasone also attenuated substance P-induced leaky site formation and increase in clearance of FITC-dextran from the cheek pouch but had no significant effects on adenosine-induced responses. Dexamethasone had no significant effects on arteriolar diameter in the cheek pouch. On balance, these data indicate that dexamethasone attenuates grain sorghum dust extract- and substance P-induced increases in macromolecular efflux from the in situ hamster cheek pouch in a specific fashion.
本研究的目的是确定地塞米松是否能减轻高粱粉尘提取物引起的原位仓鼠颊囊大分子外流量增加，如果可以，这种反应是否具有特异性。通过活体显微镜观察，我们发现高粱粉尘的水提取物可引起原位仓鼠颊囊出现显著的、浓度依赖性的渗漏位点形成，并增加异硫氰酸荧光素标记的葡聚糖（FITC-葡聚糖；分子量70 kDa）的清除率（P < 0.05）。地塞米松（10 mg/kg静脉注射）可显著减轻这种反应。地塞米松还可减轻P物质诱导的渗漏位点形成及颊囊中FITC-葡聚糖清除率的增加，但对腺苷诱导的反应无显著影响。地塞米松对颊囊小动脉直径无显著影响。总的来说，这些数据表明地塞米松以一种特异性方式减轻了高粱粉尘提取物和P物质诱导的原位仓鼠颊囊大分子外流量增加。
