Department of Anesthesiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube, Yamaguchi, 755-8505, Japan.
J Anesth. 2010 Apr;24(2):225-33. doi: 10.1007/s00540-009-0831-7. Epub 2010 Jan 29.
Fat embolism syndrome is a serious complication observed after trauma, orthopedic surgery, and cardiac surgery. We investigated brain damage in relationship to temporal profiles of water channel aquaporin 4 (AQP4) and astrocyte response to fat embolism in rats.
Triolein (2 microl) was injected into the right internal carotid artery in rats. Neurological outcome (score: range, 0-5 = no deficit-dead), brain water content, histopathology, and immunohistochemistry for AQP4 and glial fibrillary acidic protein (GFAP) were evaluated at 2 h (2 h group, n = 12), 24 h (24 h group, n = 12), and 72 h (72 h group, n = 12) after triolein injection. Saline was injected in the control (C) group (n = 12).
Neurological deficit score (median score of 2) and brain water content (mean value, 86.2%) increased significantly at 2 h with no progressive increase over 72 h. Damaged tissues with shrunken and triangular-shaped neurons with vacuole degeneration in cytoplasm and halo formation were distributed mainly, but not exclusively, to the ipsilateral hemisphere and were associated with increase in infiltration of inflammatory cells during the time course. Increases in immunostaining for AQP4 and GFAP were observed in the peri-affected region but not in the core. Reactive astrocytes with hypertrophy and dendrite elongation were detected at 72 h in the peri-affected region.
The results suggest that brain damage with edema is induced very rapidly after triolein injection in association with increase in AQP4 expression and GFAP in the peri-affected region.
脂肪栓塞综合征是创伤、矫形外科和心脏手术后观察到的一种严重并发症。我们研究了水通道蛋白 4（AQP4）的时间曲线与脂肪栓塞大鼠脑损伤的关系和星形胶质细胞的反应。
将三油酸甘油酯（2 微升）注入大鼠右侧颈内动脉。在三油酸甘油酯注射后 2 小时（2 小时组，n = 12）、24 小时（24 小时组，n = 12）和 72 小时（72 小时组，n = 12）评估神经功能结局（评分：0-5 = 无缺损-死亡）、脑水含量、组织病理学和 AQP4 和胶质纤维酸性蛋白（GFAP）的免疫组化。在对照（C）组中注射生理盐水（n = 12）。
神经功能缺损评分（中位数 2）和脑水含量（平均值 86.2%）在 2 小时显著增加，72 小时后无进一步增加。受损组织表现为神经元皱缩和三角形，细胞质空泡变性，形成晕环，主要分布在同侧半球，但并非完全局限于同侧半球，并伴有炎症细胞浸润的时间进程增加。在受影响区域的周围观察到 AQP4 和 GFAP 的免疫染色增加，但在核心区域没有增加。在受影响区域的周围，在 72 小时检测到肥大和树突伸长的反应性星形胶质细胞。
这些结果表明，三油酸甘油酯注射后，脑损伤伴水肿迅速发生，与受影响区域 AQP4 表达和 GFAP 的增加有关。
