Department of Cardiovascular Surgery, Children's National Medical Center, Washington, DC 20010, USA.
J Thorac Cardiovasc Surg. 2012 Jan;143(1):224-7. doi: 10.1016/j.jtcvs.2011.09.043. Epub 2011 Nov 1.
Our objective was to evaluate the effects of glutaraldehyde (GA) concentration, time of pretreatment, and type of tissue (porcine vs bovine) on quantitative and qualitative postimplant calcification of tissues.
Freshly obtained porcine and bovine pericardial tissues were each treated with increasing concentrations of GA (controls, 0.3125%, 0.625%, and 1.2%) for a fixed time (15 minutes) or increasing exposure times (5, 10, 20, and 30 minutes) at a fixed concentration of GA (0.625%). Pretreated tissues were subcutaneously implanted in 10-week-old Sprague-Dawley rats for 45 days before explantation. Quantitative calcium analysis was performed by flame atomic spectrophotometry. Histologic examination of tissue samples with hematoxylin and eosin and von Kossa staining was performed for cellular and inflammatory response, autolysis, and calcification.
Two-way analysis of variance indicated significantly greater calcium levels at 1.2% compared with each lower concentration for both porcine and bovine samples (P < .01). Significantly lower calcium levels were detected with increased exposure time in porcine samples (F = 6.97; P < .001); however, no significant differences in calcium levels were observed between different exposure times for bovine samples (F = 1.46; P = .23). Histologic evidence of inflammatory response with infiltration with mononuclear cells, fibroblasts, and histiocytes was seen in all grafts; however, it varied from mild to severe without any pattern. There were no differences in degree or pattern of inflammatory response according to GA concentration or time of exposure. Estimation of amount of calcification by histologic examination correlated with the quantitative assay.
Increasing GA concentration leads to greater calcification with a sharp rise in calcium levels above a concentration of 0.625%, in both bovine and porcine pericardial tissues. At a concentration of 0.625%, increasing pretreatment time is inversely related to tissue calcification for porcine pericardium but not for bovine pericardium. Differences in the tissue composition in terms of cellular content and composition of the extracellular matrix could account for the observed findings.
本研究旨在评估戊二醛（GA）浓度、预处理时间以及组织类型（猪 vs 牛）对组织植入后钙化的定量和定性的影响。
新鲜猪和牛心包组织分别用不同浓度的 GA（对照组：0.3125%、0.625%和 1.2%）处理 15 分钟，或用固定浓度的 GA（0.625%）处理 5、10、20 和 30 分钟。预处理后的组织在 10 周龄 Sprague-Dawley 大鼠皮下植入 45 天后取出。采用火焰原子分光光度法进行定量钙分析。苏木精-伊红和 von Kossa 染色的组织样本行组织学检查，以评估细胞和炎症反应、自溶和钙化情况。
方差分析表明，与较低浓度相比，1.2%浓度的 GA 可导致猪和牛心包组织的钙含量显著增加（P<0.01）。在猪心包组织中，随着暴露时间的增加，钙含量显著降低（F=6.97；P<0.001）；而在牛心包组织中，不同暴露时间的钙含量无显著差异（F=1.46；P=0.23）。所有移植物均可见单核细胞、成纤维细胞和组织细胞浸润的炎症反应的组织学证据；然而，其严重程度没有规律。GA 浓度或暴露时间不同，炎症反应的程度或模式无差异。组织学评估的钙化量与定量测定相关。
在牛和猪心包组织中，GA 浓度的增加导致钙化增加，当浓度超过 0.625%时，钙水平急剧上升。在浓度为 0.625%时，预处理时间的增加与猪心包组织的钙化呈反比关系，但与牛心包组织的钙化无关。细胞含量和细胞外基质组成方面的组织成分差异可能解释了观察到的结果。
