剪切流场中内皮细胞膜张应力累加效应的实验研究－离体血管段长度与其蛋白质代谢的相关性

用离体血管灌流试验验证冯元桢等关于血管内皮细胞的膜张应力逆血流方向累加的理论分析．用0.12N/m     

牛肺动脉单层内皮细胞长度与其血管紧张素II代谢的相关性

用离体培养的牛肺动脉内皮细胞灌流实验研究内皮细胞单层长度与其血管紧张素II代谢的相关性。牛肺动脉单层内皮细胞暴露于剪应力为0.64N/m2 的剪切流中24h后 ,两种不同长度(10cm和6cm)单层内皮细胞的血管紧张素II的平均分泌率有比较显著差异 ,10cm处理的血管紧张素II平均分泌率 (8.61±0.28pg/cm2.h)比6cm处理 (6.14±0.12pg/cm2.h)高40 % ,10cm处理的最小分泌率 (7.55pg/cm2.h)较6cm处理 (5.75pg/cm2.h)高31 % ,10cm处理的最小分泌率出现的剪切时间点比6cm处理要早6个小时。表明牛肺动脉内皮细胞单层长度与其血管紧张素II代谢 (分泌率 )间有密切的相关关系 ,进而从细胞代谢角度间接证实血管内皮细胞膜张应力存在累积效应。     

人血管内皮细胞中腺苷代谢的定量研究

目的:通过对人脐静脉内皮细胞腺苷分泌进行定性及定量研究,了解人类血管内皮细胞的腺苷代谢及机制.方法:收集并测定不同干预下细胞柱流出液中分离的人脐静脉内皮细胞分泌的腺苷量.结果:在无干预、抑制腺苷激酶及去氨酶、抑制细胞膜腺苷转运情况下,人脐静脉内皮细胞腺苷分泌率分别为13.5±7.1 pmol·min-1·mg-1、32.5±14.2 pmol·min-1·mg-1和20.8±15.7 pmol·min-1·mg-1.结论:人类血管内皮细胞内腺苷合成高于胞外,而细胞膜腺苷转运被抑制后的腺苷分泌率反而高于生理状态下分泌率,则表明腺苷在胞内分解代谢非常迅速,使部分腺苷反由胞外扩散入胞内.     

血管内皮细胞生长因子基因-2578C/A多态性与中国北方汉族人群银屑病易感性的相关性研究

目的:探讨血管内皮细胞生长因子(vascular endothelial cell growth factor,VEGF)基因-2578 C/A单核苷酸多态性位点与中国北方地区银屑病易感性的相关性.方法:随机收集2005年10月至2007年5月在哈尔滨医科大学附属一、二院皮肤科门诊就诊的246例寻常型银屑病患者(实验组)和271名正常对照个体(对照组)的外周静脉血,使用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法分析VEGF-2578 C/A多态位点基因型,并进行统计学分析.结果:在实验组中,VEGF-2578 C/A等位基因频率分别为74.80％、25.20％;在正常对照组中,VEGF-2578 C/A等位基因频率分别为76,59％、23.41％,两组VEGF-2578 C/A多态位点基因型的分布差异无统计学意义(P＞0.05).结论:VEGF基因-2578 C/A的多态性与中国北方汉族人群银屑病的易感性无明显相关性.     

血清VEGF、ATⅡ及NE与垂体瘤恶性程度的相关性及对预后预测价值分析

摘要 目的：探讨血清血管内皮生长因子（VEGF）、血管紧张素Ⅱ（ATⅡ）及去甲肾上腺素（NE）与垂体瘤恶性程度的相关性及对预后预测价值。方法：选取我院2018年1月到2021年1月收治的80例垂体瘤患者作为研究对象,将病理诊断确诊为具有侵袭性的20例恶性垂体瘤患者分为恶性组,将其余60例良性垂体瘤患者分为良性组,另选取同期来我院体检的40名健康者作为对照组。对比三组受检者血清VEGF、ATⅡ及NE表达水平,采用Spearman相关性分析法分析血清VEGF、ATⅡ及NE与垂体瘤恶性程度的相关性。随后对80例垂体瘤患者进行3年随访,发生新的转移灶、复发灶及死亡可认定为预后不良,并依照预后情况将80例垂体瘤患者分为两个亚组,即预后不良组（n=23）及预后良好组（n=57）,采用logistics回归模型分析垂体瘤预后独立影响因素。结果：三组受检者血清VEGF、ATⅡ及NE表达水平对比差异显著,恶性组高于良性组与对照组（P＜0.05）;Spearman相关分析结果显示：血清VEGF、ATⅡ及NE与垂体瘤恶性程度呈正相关（P＜0.05）;预后良好组与预后不良组患者性别、年龄、肿瘤大小、合并囊变、压迫视神经情况对比无明显差异（P＞0.05）,预后良好组与预后不良组患者侵袭性肿瘤、合并瘤卒中及血清VEGF、ATⅡ、NE水平对比差异显著（P＜0.05）;侵袭性肿瘤、血清VEGF、ATⅡ、NE水平升高为垂体瘤预后不良的独立影响因素（P＜0.05）。结论：VEGF、ATⅡ及NE与垂体瘤恶性程度呈正相关,且侵袭性肿瘤、血清VEGF、ATⅡ、NE水平升高为垂体瘤预后不良的独立影响因素。     

Evidence for the involvement of nitric oxide in the control of steroid secretion by the frog adrenal gland

Nitric oxide (NO) has been found to modulate the response of rat, bovine and human adrenocortical cells to corticotropic factors. The aim of the present study was to investigate the possible involvement of NO in the control of corticosteroid secretion in the frog Rana ridibunda. Histochemical studies using the NADPH-diaphorase reaction and immunohistochemical labeling with antibodies against NO synthase (NOS) revealed that NOS is exclusively expressed in chromaffin cells. The NO donor sodium nitroprusside (SNP) and the NO synthase inhibitor Nw-nitro--arginine (-NO₂Arg) did not modify the spontaneous production of corticosterone and aldosterone by perifused adrenal slices. Similarly, -NO₂Arg had no effect on the secretory responses induced by ACTH, angiotensin II (AII) and endothelin-1 (ET-1). In contrast, SNP significantly inhibited the stimulatory effects of ACTH, AII and ET-1 on corticosterone and aldosterone secretion. These data provide the first evidence for a modulatory role of NO on adrenocortical cell activity in amphibians.     

Prostanoids counterbalance the synergism between endothelin-1 and angiotensin II in mesenteric veins of trained rats

Exercise-induced adaptations of the modulating mechanisms that influence the angiotensin (Ang II) responses assume different features depending on the venous bed. In femoral veins, exercise mobilizes vasodilator prostanoids to cooperate with NO in order to maintain reduced Ang II responses. On the other hand, exercise’s influence on the Ang II responses in veins that drain blood from the mesenteric region has been poorly described. Therefore, the present study aimed to identify the effects of a single bout of exercise, as well as exercise training, on the Ang II responses in mesenteric veins. The present study also aimed to investigate the involvement of prostanoids, NO and ET-1 in eventual exercise-induced modifications in these veins. To this end, mesenteric veins taken from resting-sedentary, exercised-sedentary, resting-trained and exercised-trained animals were studied in organ baths. In addition, the mRNA expression of prepro-endothelin-1 (ppET-1), as well as that of the ET_A and ET_B receptors, were quantified by real-time PCR in these veins. The results show that, either in absence or in presence of L-NAME, the Ang II responses were not different between groups. In the presence of indomethacin, higher Ang II responses were observed in the resting-trained animals than in the resting-sedentary animals. This difference, however, disappeared when L-NAME, BQ-123 or BQ-788 were added during incubation. In addition, no differences in ppET-1, ET_A or ET_B mRNA expression were observed between groups. Furthermore, in the presence of PD123,319, the Ang II responses in the exercised-sedentary animals were higher than those in the resting-sedentary animals. In conclusion, exercise training mobilizes endothelin-1 (ET-1) to reinforce the Ang II-induced responses mainly through ET_A activation. On the other hand, vasodilator prostanoids are mobilized to act in parallel with NO in order to counterbalance the Ang II responses that have been potentiated by ET-1 in these trained animals.     

剪切应力对毛细血管内皮细胞代谢的影响

建立的平行平板流协腔装置适用于研究血管内皮细胞代谢对剪切流场的响应。将培养的人胚肾小球血管单层内皮细胞置于剪应力分别为５＊１０＾－５Ｎ／ｃｍ＾２,１＊１０＾－４Ｎ／ｃｍ＾２和１．５＊１０＾－４Ｎ／ｃｍ＾２的定常层流中剪切２５小时。     

In vivo imaging of oxidative stress in the kidney of diabetic mice and its normalization by angiotensin II type 1 receptor blocker

This study was undertaken to evaluate oxidative stress in the kidney of diabetic mice by electron spin resonance (ESR) imaging technique. Oxidative stress in the kidney was evaluated as organ-specific reducing activity with the signal decay rates of carbamoyl-PROXYL probe using ESR imaging. The signal decay rates were significantly faster in corresponding image pixels of the kidneys of streptozotocin-induced diabetic mice than in those of controls. This technique further demonstrated that administration of angiotensin II type 1 receptor blocker (ARB), olmesartan (5 mg/kg), completely restored the signal decay rates in the diabetic kidneys to control values. In conclusion, this study provided for the first time the in vivo evidence for increased oxidative stress in the kidneys of diabetic mice and its normalization by ARB as evaluated by ESR imaging. This technique would be useful as a means of further elucidating the role of oxidative stress in diabetic nephropathy.