人主动脉硫酸乙酰肝素蛋白聚糖对培养的人血管壁细胞生长的作用

通过培养的人主动脉平滑肌细胞（ｈＡＳＭＣ）及脐静脉内皮细胞（ｈＵＶＥＣ）,应用３Ｈ－ＴｄＲ参入、Ｎｏｒｔｈｅｒｎｂｌｏｔ分析、逆转录多聚酶链反应（ＲＴ－ＰＣＲ）、放射免疫分析（ＲＩＡ）、和紫外比色法等技术观察了人主动脉中硫酸乙酰肝素蛋白聚糖（ＨＳＰＧ）对ｈＡＳＭＣ和ｈＵＶＥＣＤＮＡ合成的作用及对血小板源生长因子（ＰＤＧＦ）、ＰＤＧＦ受体、转化生长因子β（ＴＧＦ－β）、内皮素－１（ＥＴ－１）或碱性成纤维细胞生长因子（ｂＦＧＦ）基因表达和肾素－血管紧张系统（ＲＡＳ）的影响,结果显示,ＨＳＰＧ明显抑制培养的ｈＡＳＭＣ基础的ＤＮＡ合成（ｃｐｍ值为：１０３８５±３２６３ｖｓ,２５５４１±６４２１,Ｐ＜０．０１）及外源性ＰＤＧＦ诱导的ＤＮＡ合成（ｃｐｍ值为：９８７８±１９４７ｖｓ．１３４８１±４４ｌ０,Ｐ＜０．０５）;抑制ＰＤＧＦＡ链、ＴＧＦ－Ｂｐ和ＥＴ－１ｍＲＮＡ表达,提高ＰＤＧＦａ和β受体ｍＲＮＡ的表达;显著降低ｈＡＳＭＣ培养液中血管紧张素Ⅱ（ＡｎｇⅡ）的浓度和血管紧张素转换酶（ＡＣＥ）的活性,推测ＨＳＰＧ抑制ＰＤＧＦＡ链、ＴＧＦ－β及ＥＴ－１ｍＲＮＡ表达,降低ＡＣＥ活性及ＡｎｇⅡ浓度是其抑制ｈＡＳＭＣ增殖的重要机     

Glucocorticoid amplifies vasopressin-induced phosphoinositide hydrolysis in aortic smooth muscle cells

It has been reported that glucocorticoid modifies phosphoinositide (PI) hydrolysis stimulated by vasoactive agents in vascular smooth muscle cells. In the present study, we investigated the point at which glucocorticoid affects vasopressin-induced PI hydrolysis in primary cultured rat aortic smooth muscle cells. The pretreatment with dexamethasone significantly amplified the formation of inositol trisphosphate (IP₃) induced by vasopressin in a dose-dependent manner in a range of 1 pM to 10 nM. The effect of dexamethasone was dependent on the time of pretreatment up to 8 h. Dexamethasone had little effect on the number of vasopressin receptor and its affinity to vasopressin. The pretreatment with dexamethasone also amplified the formation of IP₃ induced by NaF, a GTP-binding protein activator, or angiotensin II. 12-O-Tetradecanoylphorbol-13-acetate, a protein kinase C (PKC)-activating phorbol ester, significantly reduced the dexamethasone-induced enhancement of IP₃ formation stimulated by vasopressin, angiotensin II or NaF. 4α-Phorbol-12, 13-didecanoate, a PKC-nonactivating phorbol ester, had little effect on the enhancement by dexamethasone. These results strongly suggest that glucocorticoid amplifies vasopressin-induced PI hydrolysis at a point downstream from GTP-binding protein in primary cultured rat aortic smooth muscle cells, and that the activation of PKC has a negative feedback effect on the amplification by glucocorticoid of vasopressin-induced PI hydrolysis.     

Characterization of the phosphorylation state of natriuretic peptide receptor-C

Many internalized receptors are known to be phosphorylated within their cytoplasmic domain. Natriuretic peptide receptor-C (NPR-C) is a covalent homodimer primarily involved in the internalization of bound ligand resulting in tissue uptake and degradation of natriuretic peptides. In this report, we have investigated the phosphorylation state of NPR-C receptors present at high level in rat aortic smooth muscle cells (RASM).³² P labeled cells, NPR-C purification and phosphoamino acid analysis clearly demonstrate that NPR-C exists as a phosphoprotein in RASM cells and that phosphorylation occurs exclusively on serine residues. Transient expression of bovine NPR-C in Cos-P cells of kidney origin confirmed that phosphorylation occurs within the cytoplasmic domain of the receptor. These results provide the first evidence for NPR-C phosphorylation as well as a model for future studies of its role in altering receptor function.     

主动脉内球囊反搏术对行经皮冠状动脉介入术AMI合并CS患者的影响及术后院内死亡的危险因素分析

摘要 目的：分析主动脉内球囊反搏术（IABP）对行经皮冠状动脉介入术（PCI）急性心肌梗死（AMI）合并心源性休克（CS）患者的影响及术后院内死亡的危险因素。方法：选取2020年6月-2022年5月我院收治的105例AMI合并CS患者,将直接行PCI治疗患者设为对照组（n=59例）,行IABP辅助支持下PCI治疗患者设为研究组（n=46例）。比较两组术后心脏指标[左室射血分数（LVEF）、左室舒张末期内径（LVEDD）和左室收缩末期内径（LVESD）]、心肌酶谱指标[心肌肌钙蛋白T与肌钙蛋白I、肌酸激酶同工酶（CK-MB）]、术后主要心血管不良事件。根据患者出院时是否存活分为存活组（n=74）与死亡组（n=31）,比较两组临床资料,采用多因素Logistic回归模型分析患者院内死亡的危险因素。结果：术后两组LVEF较术前提高,LVEDD、LVESD降低,且研究组LVEF高于对照组,LVEDD、LVESD低于对照组（P＜0.05）。术后两组心肌酶谱指标较术前显著下降,且研究组肌钙蛋白I、肌钙蛋白T、CK-MB水平低于对照组（P＜0.05）。术后对照组发生5例再发心肌梗死、7例急性血栓形成,研究组分别为2例、3例（P＞0.05）;对照组死亡23例,研究组死亡8例,研究组死亡人数低于对照组（P＜0.05）。死亡组年龄、Killip分级≥Ⅲ级、高血脂、LVEF＜40%、TIMI血流分级≤Ⅱ级占比、白细胞计数、血肌酐水平高于存活组,收缩压、舒张压、血红蛋白、肌钙蛋白I、肌钙蛋白T、CK-MB、LVEF、IABP辅助低于存活组（P＜0.05）。多因素Logistic回归分析显示,年龄≥65岁、Killip分级≥Ⅲ级、LVEF＜40%、TIMI血流分级≤Ⅱ级为患者院内死亡的危险因素（P＜0.05）。结论：IABP辅助支持下的PCI能有效改善AMI合并CS患者心功能,年龄≥65岁、Killip分级≥Ⅲ级、LVEF＜40%、TIMI血流分级≤Ⅱ级为等为其院内死亡危险因素。     

中介素1-53对高磷诱导人主动脉血管平滑肌细胞ERS-线粒体凋亡通路及钙化的影响

摘要 目的：探讨中介素1-53（IMD1-53）对高磷诱导人主动脉血管平滑肌细胞（HA-VSMC）内质网应激（ERS）-线粒体凋亡通路及钙化的影响。方法：体外培养HA-VSMC,MTT法检测IMD1-53对HA-VSMC的毒性作用。HA-VSMC中添加10 mmol/L β-甘油磷酸盐进行高磷诱导,使用0.1 nmol/L或0.5 nmol/L IMD1-53干预,并在0.5 nmol/L IMD1-53干预基础上添加ERS诱导剂衣霉素（TM）,流式细胞仪检测HA-VSMC凋亡率,茜素红S染色观察HA-VSMC中钙盐沉积,酞络合酮比色法测定HA-VSMC中钙含量,分光光度法检测HA-VSMC中碱性磷酸酶（ALP）活性,蛋白质印迹法（Western blot）检测HA-VSMC中钙化以及ERS--线粒体凋亡通路相关蛋白表达。结果：IMD1-53浓度≤2.5 nmol/L时,对HA-VSMC细胞活力无明显影响（P＞0.05）,故选择对细胞无明显毒副作用的低、高2个剂量（0.1、0.5 nmol/L）进行后续实验。高磷诱导后,HA-VSMC凋亡率、钙含量、ALP活性以及Runt相关转录因子-2（Runx2）、骨桥蛋白（OPN）、Bcl-2相关X蛋白（Bax）、裂解的半胱氨酰天冬氨酸蛋白酶-3（cleaved caspase-3）、葡萄糖调节蛋白78（GRP78）、C/EBP同源蛋白（CHOP）、感受器活化转录因子6（ATF6）、p-需肌醇酶1（IRE1）/IRE1蛋白表达水平升高（P＜0.05）,橘红色结节明显增多,骨保护素（OPG）、B细胞淋巴瘤/白血病-2（Bcl-2）蛋白表达水平降低（P＜0.05）。0.1 nmol/L和0.5 nmol/L IMD1-53干预处理均可降低HA-VSMC凋亡率、钙含量、ALP活性以及Runx2、OPN、Bax、cleaved caspase-3、GRP78、CHOP、ATF6、p-IRE1/IRE1蛋白表达水平（P＜0.05）,明显减少橘红色结节,升高OPG、Bcl-2蛋白表达水平（P＜0.05）。ERS诱导剂TM可升高HA-VSMC中GRP78、CHOP、ATF6、p-IRE1/IRE1蛋白表达水平,并减弱IMD1-53抑制高磷诱导的HA-VSMC ERS、凋亡和钙化的作用。结论：IMD1-53可减轻高磷诱导的HA-VSMC钙化,其作用机制可能与抑制ERS-线粒体凋亡通路激活,减少细胞凋亡有关。     

Dual pathways for tactile sensory information to thoracic interneurons in the cockroach

The escape system of the American cockroach is both fast and directional. In response to wind stimulation both of these characteristics are largely due to the properties of the ventral giant interneurons (vGIs), which conduct sensory information from the cerci on the rear of the animal to type A thoracic interneurons (TI_As) in the thoracic ganglia. The cockroach also escapes from tactile stimuli, and although vGIs are not involved in tactile-mediated escapes, the same thoracic interneurons process tactile sensory information. The response of TI_As to tactile information is typically biphasic. A rapid initial depolarization is followed by a longer latency depolarization that encodes most if not all of the directional information in the tactile stimulus. We report here that the biphasic response of TI_As to tactile stimulation is caused by two separate conducting pathways from the point of stimulation to the thoracic ganglia. Phase 1 is generated by mechanical conduction along the animal's body cuticle or other physical structures. It cannot be eliminated by complete lesion of the nerve cord, and it is not evoked in response to electrical stimulation of abdominal nerves that contain the axons of sensory receptors in abdominal segments. However, it can be eliminated by lesioning the abdominal nerve cord and nerve 7 of the metathoracic ganglion together, suggesting that the relevant sensory structures send axons in nerve 7 and abdominal nerves of anterior abdominal ganglia. Phase 2 of the TI_As tactile response is generated by a typical neural pathway that includes mechanoreceptors in each abdominal segment, which project to interneurons with axons in either abdominal connective. Those interneurons with inputs from receptors that are ipsilateral to their axon have a greater influence on TI_As than those that receive inputs from the contralateral side. The phase 1 response has an important role in reducing initiation time for the escape response. Animals in which the phase 2 pathway has been eliminated by lesion of the abdominal nerve cord are still capable of generating a partial startle response with a typically short latency even when stimulated posterior to the lesion. © 1995 John Wiley & Sons, Inc.     

Macroscopic Ca2+ -Na+ and K+ currents in single heart and aortic cells

Summary The whole-cell voltage clamp technique was used to study the slow inward currents and K⁺ outward currents in single heart cells of embryonic chick and in rabbit aortic cells. In single heart cells of 3-day-old chick embryo three types of slow inward Na⁺ currents were found. The kinetics and the pharmacology of the slow I_Na, were different from those of the slow Ica in older embryos. Two types of slow inward currents were found in aortic single cells of rabbit; angiotensin 11 increased the sustained type and d-cAMP and d-cGMP decreased the slow transient component. Two types of outward K⁺ currents were found in both aortic and heart cells. Single channel analysis demonstrated the presence of a high single K⁺ channel conductance in aortic cells. In cardiac and vascular smooth muscles, slow inward currents do share some pharmacological properties, although the regulation of these channels by cyclic nucleotides and several drugs seems to be different.     

Trace element changes in sclerotic heart valves from patients are expressed in their blood

The pathogenesis of some heart diseases has been associated with changes in the balance of certain trace elements. However, whether blood trace element changes exist that are related to changes in the cardiovascular system are, in most cases, unknown. In this study, blood trace element levels were analysed in 46 patients with non-rheumatic aortic valve sclerosis that were previously shown to have a disturbed trace element balance in their valve tissue, including 11/15 elements. Results showed significant changes of blood levels of 8/15 trace elements in these patients when compared with blood levels in 46 healthy controls. Of these elements, Cd and Mg were the only elements that increased in both blood and valves. Cu and Se were increased in blood but decreased in valves, whereas Co and Zn were decreased in blood but increased in valves. Several elements (As, Ca, Fe, Pb, and V) were unchanged in blood although changed in valves. Although Mn and Hg showed changes in blood, this was not evident in the valves. Al and Ag were the only elements that did not change in both blood and valves. Significant covariation in blood and valve levels was only observed for Al and Pb. The recorded pattern of trace element changes indicates a complex competition/exchange between body compartments in this disease, where the increased blood Cu/Zn ratio suggests an ongoing infectious/inflammatory process.     

Gender-related differences in adhesion, growth and differentiation of vascular smooth muscle cells are enhanced in serum-deprived cultures

In 1-day cultures with 10% serum, the number of rat aortic smooth muscle cells (VSMC) adhering to the growth support was similar in cells from both sexes, whereas in 1% serum, the number of VSMC from male donors was lower. In 10% serum medium, the doubling time was significantly shorter and the number of [3H]thymidine-labelled nuclei was higher in cells of high passage from male rats. In serum-free medium, these differences increased and were also seen in cells of low passage number. Morphologically, the cells in male-derived cultures at higher passage number were mainly spindle-shaped, formed well-developed 'hills and valleys' and possessed longitudinally oriented bundles of alpha-actin-containing microfilaments. Most cells from female rats were flat, polygonal, the multilayered 'hills' were less prominent, with alpha-actin microfilaments forming a mesh-like network.