Biondo-Simões Maria de Lourdes Pessole, Ioshii Sergio Ossamu, Zazula Ana Denise, Biondo-Simões Rachel
Metodologia Científica da PUCPR.
Acta Cir Bras. 2005;20 Suppl 1:204-10.
The aging of the population has led to an increased number of interventions in elderly patients, with hypothyroidism, even at the subclinical level, being a common situation among these patients. The objective of the present study was to determine the influence of hypothyroidism on the healing process of colon anastomoses in aged rats.
96 male Wistar rats were used, 48 of them young and 48 old. Half the young animals and half the old ones were euthyroid and half were hypothyroid. Hypothyroidism was obtained by total thyroidectomy. Thirty days after surgery the animals were submitted to median laparotomy followed by transverse colotomy of the left colon with end-to-end anastomosis and laparorrhaphy. Six animals from each group were submitted to euthanasia by drawing lots on the 3rd, 7th and 14th postoperative day and submitted to macroscopic, resistance, and histopathological analysis of the anastomoses.
No dehiscence was observed and the gain of resistance and the general histological evolution in terms of epithelialization and inflammatory reaction was similar in all groups. Analysis of total collagen content revealed that the anastomoses of young and old animals showed the same behavior on the 3rd day, although less collagen was observed in hypothyroid animals (YN x YH p = 0.0000; ON x OH p = 0.0000). This behavior persisted on the 7th and 14 day. Less collagen I was present in the anastomoses of hypothyroid animals on the 3 (YN x YH p = 0.0015; ON x OH p = 0.0000), 7th (YN x YH p = 0.0006; ON x OH p = 0.0001) and 14th day (YN x YH p = 0.0181; ON x OH p = 0.0057), the same occurring for collagen III on the 3rd (x YH p = 0.0007; ON x OH p = 0.0260), 7th (YN x YH p = 0.0160; ON x OH p = 0.2670) and 14th day (YN x YH p = 0.0000; ON x OH p = 0.0030).
Analysis of the results permitted us to conclude that lower collagen concentration du to low synthesis and delayed scar maturation in the anastomoses occurred and was much more due to hypothyroidism than to aging.
人口老龄化导致老年患者的干预措施增多，甲状腺功能减退，即使是亚临床水平，在这些患者中也是常见情况。本研究的目的是确定甲状腺功能减退对老年大鼠结肠吻合口愈合过程的影响。
使用96只雄性Wistar大鼠，其中48只为年轻大鼠，48只为老年大鼠。年轻动物的一半和老年动物的一半甲状腺功能正常，另一半甲状腺功能减退。通过全甲状腺切除术诱导甲状腺功能减退。手术后30天，对动物进行正中剖腹术，然后对左结肠进行横切术并进行端端吻合和腹壁缝合术。每组6只动物在术后第3、7和14天通过抽签进行安乐死，并对吻合口进行宏观、阻力和组织病理学分析。
未观察到吻合口裂开，所有组在阻力增加以及上皮化和炎症反应方面的总体组织学演变相似。总胶原蛋白含量分析显示，年轻和老年动物的吻合口在第3天表现相同，尽管甲状腺功能减退的动物中观察到的胶原蛋白较少（年轻正常组与年轻甲状腺功能减退组p = 0.0000；老年正常组与老年甲状腺功能减退组p = 0.0000）。这种情况在第7天和第14天持续存在。在第3天（年轻正常组与年轻甲状腺功能减退组p = 0.0015；老年正常组与老年甲状腺功能减退组p = 0.0000）、第7天（年轻正常组与年轻甲状腺功能减退组p = 0.0006；老年正常组与老年甲状腺功能减退组p = 0.0001）和第14天（年轻正常组与年轻甲状腺功能减退组p = 0.0181；老年正常组与老年甲状腺功能减退组p = 0.0057），甲状腺功能减退动物的吻合口中I型胶原蛋白较少，III型胶原蛋白在第3天（年轻正常组与年轻甲状腺功能减退组p = 0.0007；老年正常组与老年甲状腺功能减退组p = 0.0260）、第7天（年轻正常组与年轻甲状腺功能减退组p = 0.0160；老年正常组与老年甲状腺功能减退组p = 0.2670）和第14天（年轻正常组与年轻甲状腺功能减退组p = 0.0000；老年正常组与老年甲状腺功能减退组p = 0.0030）也是如此。
对结果的分析使我们得出结论，吻合口中由于合成减少和瘢痕成熟延迟导致胶原蛋白浓度降低，这更多是由于甲状腺功能减退而非衰老所致。
