Faa Armando, Xanthos Theodoros, Papalois Apostolos, Locci Annalisa, Pampaloni Pietro, Pais Maria Elena, Aroni Filippia, Gazzolo Diego, Faa Gavino, Iacovidou Nicoletta
Department of Pathology, University of Cagliari , Cagliari , Italy .
J Matern Fetal Neonatal Med. 2013 Oct;26 Suppl 2:72-6. doi: 10.3109/14767058.2013.830410.
The evaluation of the expression of S100B protein, in the swine heart in an experimental model of hypoxia - reoxygenation.
Normocapnic hypoxia was induced in 40 male Landrace/Large White neonatal piglets by decreasing the inspired concentration of oxygen to 6-8%. When animals developed bradycardia or severe hypotension, reoxygenation was initiated. Piglets were allocated in four groups of 10, according to the oxygen concentration they were reoxygenated with: Group 1, 2, 3 and 4 resuscitated with 18%, 21%, 40% and 100% oxygen, respectively. The animals were further classified into 4 groups according with the time required for reoxygenation: group A (<15 min); group B (16-60 min); group C (>60 min); group D (deceased animals).
Immunostaining for S100B protein was detected in 14 out of the 40 heart samples (35%), both inside the cytoplasm of cardiomyocytes and as globular deposits in the interstitial spaces. Significant differences were observed among groups 1-4 regarding S100B expression. Reactivity for S100B in cardiac cells was detected in 50%, 50%, 10% and 33% of animals in groups 1 and 2, 3 and 4, respectively. Marked differences were also observed among groups A-D: 75%, 33%, 12% and 22% of the animals in group 1, 2, 3 and 4, respectively, showed reactivity for S100B in the heart.
Expression of S100B protein occurred in the heart of some of newborn piglets following severe hypoxia. S100B storage in cardiomyocytes correlates with the different oxygen concentration used during reoxygenation, being higher in piglets reoxygenated with 18% and 21%, and lower in animals reoxygenated with 40% oxygen. Intermediate levels of S100B expression were found in 100% O2-treated animals. The finding of a higher percentage of S100B-immunoreactive hearts in piglets with a fast recovery and the detection of a decreased reactivity in animals with a slow and a very slow recovery clearly indicates S100B protein as an early protective factor with a positive prognostic value in asphyxiated newborn piglets.
评估S100B蛋白在缺氧-复氧实验模型猪心脏中的表达情况。
通过将吸入氧浓度降至6-8%，诱导40只雄性长白/大白新生仔猪发生常碳酸血症性缺氧。当动物出现心动过缓或严重低血压时，开始复氧。根据复氧时所用的氧浓度，将仔猪分为4组，每组10只：第1组、第2组、第3组和第4组分别用18%、21%、40%和100%的氧气进行复苏。根据复氧所需时间，将动物进一步分为4组：A组（<15分钟）；B组（16-60分钟）；C组（>60分钟）；D组（死亡动物）。
在40个心脏样本中的14个（35%）检测到S100B蛋白免疫染色，既存在于心肌细胞胞质内，也存在于间质间隙的球状沉积物中。第1-4组在S100B表达方面存在显著差异。第1组和第2组、第3组和第4组中，分别有50%、50%、10%和33%的动物心脏细胞检测到S100B反应性。A-D组之间也观察到明显差异：第1组、第2组、第3组和第4组中，分别有75%、33%、12%和22%的动物心脏显示出S100B反应性。
严重缺氧后，部分新生仔猪心脏中出现S100B蛋白表达。心肌细胞中S100B的储存与复氧时所用的不同氧浓度相关，用18%和21%氧气复氧仔猪中的S100B储存量较高，用40%氧气复氧的动物中较低。在100%氧气处理的动物中发现S100B表达处于中等水平。在恢复快的仔猪中，S100B免疫反应性心脏的比例较高，而在恢复慢和非常慢的动物中检测到反应性降低，这一发现清楚地表明S100B蛋白是窒息新生仔猪中具有积极预后价值的早期保护因子。
