Olson M E, Morck D W, Ceri H, Lee C C, Chancellor M B
University of Calgary, Canada.
Urology. 1998 Nov;52(5):915-9. doi: 10.1016/s0090-4295(98)00338-0.
Autologous fat has been used as a bulking implant material for stress urinary incontinence. There is considerable controversy as to the ultimate fate of the grafted fat. This study was conducted to determine the fate of autogenous fat implanted into the bladder of rats.
Two groups of adult female rats were studied. In the test animals (group 1, n = 20), mesenteric adipose tissue (1 mL) was harvested and homogenized with an equal weight of sterile saline. Using a 25-gauge needle, 0.5 g of saline-fat mixture was injected into the dorsal bladder neck submucosa. Control animals (group 2, n = 12) were injected with sterile saline only. A subset of animals from each group were killed after 7, 35, 105, and 1 50 days, and the bladder and urethra were fixed. The fixed tissue was examined microscopically and photographed at each follow-up period.
Seven days after injection of fat, there was a pronounced acute inflammatory reaction with numerous polymorphonuclear leukocytes and macrophages at the site of fat injection. There was minimal inflammatory reaction at the site of saline injection. By day 35, most of the fat had been eliminated by these phagocytes because of severe acute and chronic inflammation. By day 105, the submucosa tissue of the experimental rats had returned to normal visually and to a flat surface, lacking the appearance of a sizable "bulge" as shown at days 0 and 7. Histopathologic findings were also similar to the control rats. Inflammatory cells were no longer present by day 105.
The implantation of homogenized, autologous fat in the rat urinary bladder submucosa causes acute and chronic inflammation and fat necrosis. The severe phagocytosis at the implant sites eliminates the vast majority of the devitalized implanted fat during the first month.
自体脂肪已被用作压力性尿失禁的填充植入材料。关于移植脂肪的最终命运存在相当大的争议。本研究旨在确定植入大鼠膀胱的自体脂肪的命运。
对两组成年雌性大鼠进行研究。在试验动物（第1组，n = 20）中，采集肠系膜脂肪组织（1 mL），并与等重量的无菌生理盐水匀浆。使用25号针头，将0.5 g生理盐水 - 脂肪混合物注入膀胱颈背侧黏膜下层。对照动物（第2组，n = 12）仅注射无菌生理盐水。每组中的一部分动物在7、35、105和150天后处死，膀胱和尿道进行固定。在每个随访期对固定组织进行显微镜检查并拍照。
注射脂肪7天后，脂肪注射部位出现明显的急性炎症反应，有大量多形核白细胞和巨噬细胞。生理盐水注射部位炎症反应轻微。到第35天，由于严重的急性和慢性炎症，这些吞噬细胞已清除了大部分脂肪。到第105天，实验大鼠的黏膜下层组织在外观上已恢复正常且表面平整，没有第0天和第7天出现的明显“隆起”。组织病理学结果也与对照大鼠相似。到第105天炎症细胞不再存在。
在大鼠膀胱黏膜下层植入匀浆自体脂肪会引起急性和慢性炎症以及脂肪坏死。植入部位的严重吞噬作用在第一个月内消除了绝大多数失活的植入脂肪。
