Li Xiang, Wu Bing-Xia, Li He, Wang Meng-Meng, Ma Ke-Tao, Gu Qiang
Department of Pediatrics, First Affiliated Hospital of Shihezi University, Shihezi, Xinjiang 832000, China.
Zhongguo Dang Dai Er Ke Za Zhi. 2019 Feb;21(2):189-194. doi: 10.7499/j.issn.1008-8830.2019.02.017.
To study the effect of calcium-sensitive receptors (CaSR) on the expression of endothelial nitric oxide synthase (eNOS) and the concentration of nitric oxide (NO) in a neonatal mouse model of persistent pulmonary hypertension (PPH).
Eighty neonatal C57BL/6 mice were randomly divided into control, PPH, agonist and antagonist groups. The control group was exposed to air, and the other three groups were exposed to 12% oxygen. The agonist and antagonist groups were intraperitoneally injected with a CaSR agonist (GdCl 16 mg/kg) and a CaSR antagonist (NPS2390, 1 mg/kg), respectively, while the PPH and control groups were intraperitoneally injected with normal saline instead. All mice were treated for 14 days. Alveolar development and pulmonary vessels were assessed by hematoxylin-eosin staining. The protein and mRNA expression of eNOS and its localization in lung tissues were determined by Western blot, qRT-PCR and immunohistochemistry. The levels of brain natriuretic peptide (BNP) and NO in lung homogenate were determined using ELISA.
Compared with the control group, the PPH and agonist groups showed significant increases in alveolar mean linear intercept, the percent wall thickness of pulmonary arterioles, right to left ventricular wall thickness ratio (RV/LV) and BNP concentration, but a significant reduction in radial alveolar count (P<0.05). The antagonist group had significant improvements in all the above indices except RV/LV compared with the PPH and agonist groups (P<0.05). Compared with those in the control group, the protein and mRNA expression of eNOS and NO concentration were significantly increased in the PPH group and increased more significantly in the agonist group, but were significantly reduced in the antagonist group (P<0.05).
CaSR plays an important role in the development of PPH in neonatal mice, possibly by increasing eNOS expression and NO concentration.
在新生小鼠持续性肺动脉高压（PPH）模型中，研究钙敏感受体（CaSR）对内皮型一氧化氮合酶（eNOS）表达及一氧化氮（NO）浓度的影响。
将80只新生C57BL/6小鼠随机分为对照组、PPH组、激动剂组和拮抗剂组。对照组暴露于空气中，其他三组暴露于12%氧气中。激动剂组和拮抗剂组分别腹腔注射CaSR激动剂（GdCl 16 mg/kg）和CaSR拮抗剂（NPS2390，1 mg/kg），而PPH组和对照组腹腔注射生理盐水。所有小鼠均治疗14天。通过苏木精-伊红染色评估肺泡发育和肺血管情况。采用蛋白质免疫印迹法、实时定量聚合酶链反应和免疫组织化学法测定肺组织中eNOS的蛋白质和mRNA表达及其定位。使用酶联免疫吸附测定法测定肺匀浆中脑钠肽（BNP）和NO的水平。
与对照组相比，PPH组和激动剂组的肺泡平均线性截距、肺小动脉壁厚度百分比、右心室与左心室壁厚度比值（RV/LV）及BNP浓度显著增加，但肺泡径向计数显著减少（P<0.05）。与PPH组和激动剂组相比，拮抗剂组除RV/LV外，上述所有指标均有显著改善（P<0.05）。与对照组相比，PPH组中eNOS的蛋白质和mRNA表达及NO浓度显著增加，激动剂组增加更显著，而拮抗剂组显著降低（P<0.05）。
CaSR在新生小鼠PPH的发生发展中起重要作用，可能是通过增加eNOS表达和NO浓度来实现的。
