Ishizuka T, Hayashi T, Ishihara M, Yoshizumi Y, Aiko S, Nakamura S, Yura H, Kanatani Y, Nogami Y, Maehara T
Dept. of Surgery II, National Defense Medical College, Tokorozawa, Saitama, Japan.
Endoscopy. 2007 May;39(5):428-33. doi: 10.1055/s-2007-966393.
We studied the ability of a photocrosslinkable chitosan in DMEM/F12 medium to maintain submucosal thickness and to reduce bleeding after mucosal resection. We also investigated the behavior of chitosan hydrogels with regard to wound healing.
The gastric submucosal layer of heparinized rats was injected with the photocrosslinkable chitosan in medium (which was then irradiated with ultraviolet light to form a hydrogel), or with sodium hyaluronate, or hypertonic saline, and three investigations were done, using three different sets of rats. The first and second were measurement of the thickness of the layer, and of the amount of bleeding induced by mucosal resection, respectively. Thirdly, the effects of the chitosan hydrogel on wound healing were examined histologically.
Gastric submucosal layers of chitosan hydrogel-treated animals remained significantly thicker than those of other groups for at least 6 h after injection. The total amount of bleeding 20 min after mechanical mucosal resection was 170.0 +/- 20.0 mg, 678.3 +/- 226.3 mg, and 1020.0 +/- 104.1 mg in the chitosan hydrogel, sodium hyaluronate, and hypertonic saline groups, respectively. Histological study revealed that the focus of bleeding was surrounded by chitosan hydrogel and that almost all the hydrogel was biodegraded within 4 weeks. Furthermore, a discernible, but not statistically significant effect of the chitosan hydrogel on wound healing was observed.
The chitosan hydrogel produced mucosal elevation after submucosal injection with ultraviolet irradiation, and it significantly reduced bleeding after mucosal resection. Our newly developed chitosan hydrogel in medium might be a promising submucosal agent for endoscopic mucosal resection.
我们研究了可光交联壳聚糖在DMEM/F12培养基中维持黏膜下层厚度以及减少黏膜切除术后出血的能力。我们还研究了壳聚糖水凝胶在伤口愈合方面的表现。
给肝素化大鼠的胃黏膜下层注射培养基中的可光交联壳聚糖（随后用紫外线照射形成水凝胶），或透明质酸钠，或高渗盐水，使用三组不同的大鼠进行三项研究。第一项和第二项分别是测量该层的厚度以及黏膜切除引起的出血量。第三，通过组织学检查壳聚糖水凝胶对伤口愈合的影响。
注射后至少6小时，壳聚糖水凝胶处理动物的胃黏膜下层明显比其他组厚。机械性黏膜切除术后20分钟，壳聚糖水凝胶组、透明质酸钠组和高渗盐水组的总出血量分别为170.0±20.0毫克、678.3±226.3毫克和1020.0±104.1毫克。组织学研究显示，出血部位被壳聚糖水凝胶包围，并且几乎所有水凝胶在4周内被生物降解。此外，观察到壳聚糖水凝胶对伤口愈合有明显但无统计学意义的影响。
壳聚糖水凝胶在黏膜下注射并经紫外线照射后可使黏膜隆起，并且显著减少黏膜切除术后的出血。我们新开发的培养基中的壳聚糖水凝胶可能是一种有前景的内镜黏膜下切除黏膜下剂。
