Medical Sciences Graduate Program, McMaster University, Hamilton, ON, Canada.
Microcirculation. 2011 Nov;18(8):613-22. doi: 10.1111/j.1549-8719.2011.00123.x.
To establish an in vivo mouse model of the urinary bladder microcirculation, and characterize the molecular mechanisms of endotoxin-induced leukocyte recruitment.
The murine model was adapted from a technique previously reported for the rat. Mouse bladder microcirculation was observed using intravital microscopy, four hours after intravesical challenge with lipopolysaccharide (LPS) and leukocyte-endothelial interactions were examined. Molecular mechanisms of leukocyte recruitment were identified using antibodies to adhesion molecules and chemokines.
LPS from Escherichia coli administered intravesically resulted in a significant increase in leukocyte adhesion and rolling at four hours post stimulation. LPS from Pseudomonas aeruginosa administered at similar doses resulted in a significant, but lower increase in leukocyte adhesion after four hours compared with E. coli LPS. Leukocyte adhesion within the bladder microcirculation was dependent on α(4) -integrins and ICAM-1, whereas leukocyte rolling was P-selectin dependent, but α(4) -integrin independent. Blockade of MIP-2 and KC did not alter leukocyte-endothelial interactions. The bladder endothelium expressed P-selectin, ICAM-1, VCAM-1, MIP-2, and MCP-1. Only VCAM-1 endothelial expression was significantly increased after LPS stimulation.
The mouse model of the urinary bladder microcirculation is suitable for the study of inflammatory responses during urinary tract infection (UTI) in vivo.
建立活体小鼠膀胱微循环模型，并对内毒素诱导白细胞募集的分子机制进行特征分析。
该小鼠模型改编自先前报道的大鼠技术。通过腹腔内注射脂多糖（LPS）后 4 小时进行活体显微镜观察，研究膀胱微血管内的白细胞-内皮相互作用。使用抗黏附分子和趋化因子抗体鉴定白细胞募集的分子机制。
在给予类似剂量的铜绿假单胞菌 LPS 后，与大肠杆菌 LPS 相比，白细胞黏附在 4 小时后显著增加，但增加幅度较小。膀胱微循环中的白细胞黏附依赖于α（4）整合素和 ICAM-1，而白细胞滚动依赖于 P 选择素，但不依赖于α（4）整合素。阻断 MIP-2 和 KC 并不改变白细胞-内皮相互作用。膀胱内皮表达 P 选择素、ICAM-1、VCAM-1、MIP-2 和 MCP-1。只有 VCAM-1 的内皮表达在 LPS 刺激后显著增加。
该小鼠膀胱微循环模型适用于研究尿路感染（UTI）期间体内炎症反应。
