血管紧张素Ⅱ受体2型对创面愈合过程中微血管形成的影响

目的：观察血管紧张素Ⅱ受体2型（AT2R）在创面肉芽组织微血管形成中的作用,探讨其影响新血管形成的可能机制.方法：用打孔器在小鼠背部制成直径6.0 mm全层皮肤缺损创面模型,将24只C57BL/6J小鼠分成两组（n=12）：PD123319处理组腹腔注射特异性AT2R阻断剂PD123319（10 mg·kg-1·d-1）,对照组腹腔注射等量生理盐水.分别在创面形成后第3、5、7、和14天取创面组织标本,每个时间点3只小鼠.另有6只作为正常对照.采用HE染色观察肉芽组织和新血管形成的情况,应用ELISA法检测创面愈合过程中创面局部组织血管内皮生长因子受体1（VEGFR1）的变化,免疫组织化学方法检测正常小鼠皮肤与创面愈合过程中创面局部组织AT2R的表达情况.结果：正常小鼠皮肤AT2R在整个表皮层均有阳性表达,在真皮层,AT2R主在微血管内皮细胞,皮肤附件如毛囊、汗腺、皮脂腺有阳性表达.在小鼠全层皮肤缺损创面愈合过程中,创面局部组织AT2R产生逐渐增加,第7天达到峰值,以后逐渐下降.在伤后第5天和第7天,对照组创面肉芽组织的面积分别为（9.37±0.53）mm2和（7.15±0.42）mm2,PD123319处理组创面肉芽组织面积分别为（11.51±0.98）mm2和（9.32±0.67）mm2,两组间差异有统计学意义（P〈0.05）.PD123319可随时间的延长明显增加肉芽组织中VEGFR1的表达和血管形成的组织学评分,在第7天达到峰值,两组间差异有显著性（P〈0.05）,然后均逐渐下降.结论：在创面愈合过程中,AT2R可能参与创面的愈合及其后期的塑性改建,并通过调节VEGFR1水平影响肉芽组织中微血管的形成.     

血管紧张素转化酶和血管紧张素Ⅱ受体在银屑病患者皮损中的表达

目的:观察血管紧张素转化酶(ACE)、血管紧张素Ⅱ1型(AT1)和2型(AT2)受体在银屑病患者皮损和非皮损以及正常皮肤中的表达特征,探讨血管紧张素系统与银屑病发病机制中表皮角质形成细胞过度增殖和异常角化的关系。方法:用免疫荧光组织化学方法和常规病理技术检测ACE、AT1和AT2受体在12例银屑病患者典型皮损和非皮损以及5例正常皮肤组织中的表达和分布规律。结果:在正常皮肤组织,ACE的表达主要定位于表皮基底层角质形成细胞,AT1和AT2受体在整个表皮层均有阳性表达,但荧光信号较弱。在银屑病患者非皮损处,ACE、AT1和AT2受体的表达与正常皮肤相似。在银屑病皮损中的表皮层角质形成细胞ACE表达明显增加,整个表皮层均可见较强绿荧光颗粒,真皮浅层成纤维细胞亦可见绿色荧光颗粒。和ACE的表达变化类似,在银屑病皮损中AT1和AT2受体表达也明显增加,表皮全层可见分布密集的荧光颗粒,真皮浅层成纤维细胞也可见荧光颗粒。结论:在银屑病患者皮损处肾素-血管紧张素系统(RAS)被激活,AngⅡ产生和其受体表达增加,AngⅡ可能通过其受体参与银屑病患者皮损处角质形成细胞的过度增殖角化不全的组织学改变。     

The change of angiotensin Ⅱ production and its receptor expression during wound healing: possible role of angiotensin Ⅱ in wound healing

Objective This study was undertaken to observe the change in the local level of angiotensin Ⅱ (Ang Ⅱ) and the expression of its corresponding receptors AT1 and AT2 during wound healing, and explore the possible role of Ang Ⅱ in wound healing . Methods A model of full-thickness cutaneous wound was developed on the back of C57/BL6 mice. Specimens were taken from the wound of each mouse on the day 0, 1, 3, 5, 7, 9, 11, 13 and 15 after wounding. The change in the generation of Ang Ⅱ in wounded tissue during the healing process was detected with ELISA. The proliferation and the apoptosis of cells were detected by bromodeoxyuridine (Brdu) and terminal deoxyuncleotidyl transferase mediated deoxyuridine triphosphate nick end labeling (TUNEL) method in wounded skin during the healing process, respectively. The cellular localization and the mRNA level change of Ang Ⅱ receptors in wounded tissue during healing were detected with immunostaining and RT-PCR. Results Ang Ⅱ produced in wounded skin was increased in the first 7 days to reach the peak, and then gradually decreased during wound healing. BrdU labeling index was increased gradually in the first 7 days to reach the peak, and then gradually decreased during wound healing. The number of TUNEL-positive cells was increased slowly in the first 7 days after wounding. The increase in the number of TUNEL-positive cells was more markedly after epithelization of the wound. In normal mice, AT1 and AT2 receptor were found positively expressed in the whole epidermal layer, while positive expression was only found in the endothelial cells of the capillary vessels within the dermal layer, and positive expression was also found in appendages of the skin, i.e. hair follicle, sweat gland and sebaceous gland respectively. Positive staining signal of both AT1 and AT2 receptors were increased in the first 7 days to reach the peak, then gradually decreased. Expression of AT2R was increased again following the epithelization of wound. The result of RT-PCR showed that the expression of both AT1 and AT2 receptors was detectable, and AT1 receptor was increased in the first 7 days to the peak, and then gradually decreased during wound healing, while AT2 receptor expression reached its peak value on day 7, then gradually decreased, and increased again following the epithelization of wound. Conclusions These results indicate that Ang Ⅱ participate in wound repair and related to remolding in the late stage of wound healing through the change in production of angiotensin Ⅱ and expression of AT1 and AT2 receptors. AT1 receptor might be closely associated with cell proliferation,while AT2 receptor might play a role in cell apoptosis and remolding during wound healing.     

血管紧张素Ⅱ受体在增生性瘢痕成纤维细胞胶原合成中的作用

背景:最新研究发现,血管紧张素Ⅱ与皮肤纤维化病变的发生和发展有关,然而有关血管紧张素Ⅱ受体在人增生性瘢痕成纤维细胞中的表达及作用鲜见报道.目的:观察血管紧张素Ⅱ 1型受体和2型受体在人增生性瘢痕成纤维细胞中的表达,并探讨它们在成纤维细胞胶原合成中的作用.设计、时间及地点:对比观察,于2006-08/2007-11在解放军广州军区广州总医院医学实验中心完成.对象:取住院患者增生性瘢痕18例,男10例,女8例,年龄19～47岁,将增生性瘢痕标本分为两组,每组各9例.正常皮肤7例,取自增生性瘢痕切除患者的正常皮肤.所有取材部位未经任何治疗,标本经无菌取材后分成2份,其中一份用40 g/L多聚甲醛固定后用于免疫组织化学检测,另一份用于成纤维细胞培养.方法:采用免疫组织化学的方法和放射性配体受体结合测定法观察人增生性瘢痕组织中成纤维细胞血管紧张素Ⅱ 1型受体和2型受体的表达,并用体外细胞培养技术观察2种受体在人增生性瘢痕成纤维细胞胶原合成中的作用.主要观察指标:2种受体在增生性瘢痕组织成纤维细胞中的表达及在人增生性瘢痕成纤维细胞胶原合成中的作用.结果:①在增生性瘢痕的成纤维细胞可见1型受体和2型受体表达,阳性染色信号较强.放射性配体受体结合测定法显示在培养的增生性瘢痕的成纤维细胞有1型受体和2型受体,受体密度分别为(10.69±2.15),(4.9±1.05)fmol/106个细胞.②在培养的人增生性瘢痕成纤维细胞,血管紧张素Ⅱ明显促进成纤维细胞胶原的合成,1 型受体阻断剂Valsartan明显抑制血管紧张素Ⅱ的这种促进作用,2型受体拮抗剂PD123319明显增强血管紧张素Ⅱ的这种作用.结论:在增生性瘢痕的成纤维细胞表达血管紧张素Ⅱ 1型受体和2型受体,血管紧张素Ⅱ通过激活2种受体对成纤维细胞胶原的合成产生相反的作用,血管紧张素Ⅱ产生和受体表达比例的变化可能影响瘢痕的形成和成熟.     

血管紧张素Ⅱ受体在增生性瘢痕成纤维细胞胶原合成中的作用

背景:最新研究发现，血管紧张素Ⅱ与皮肤纤维化病变的发生和发展有关，然而有关血管紧张素Ⅱ受体在人增生性瘢痕成纤维细胞中的表达及作用鲜见报道。 目的:观察血管紧张素Ⅱ1型受体和2型受体在人增生性瘢痕成纤维细胞中的表达，并探讨它们在成纤维细胞胶原合成中的作用。 设计、时间及地点:对比观察，于2006-08/ 2007-11在解放军广州军区广州总医院医学实验中心完成。 对象:取住院患者增生性瘢痕18例，男10例，女8例，年龄19~47岁，将增生性瘢痕标本分为两组，每组各9例。正常皮肤7例，取自增生性瘢痕切除患者的正常皮肤。所有取材部位未经任何治疗，标本经无菌取材后分成2份，其中一份用40 g/L多聚甲醛固定后用于免疫组织化学检测，另一份用于成纤维细胞培养。 方法:采用免疫组织化学的方法和放射性配体受体结合测定法观察人增生性瘢痕组织中成纤维细胞血管紧张素Ⅱ1型受体和2型受体的表达，并用体外细胞培养技术观察2种受体在人增生性瘢痕成纤维细胞胶原合成中的作用。 主要观察指标:2种受体在增生性瘢痕组织成纤维细胞中的表达及在人增生性瘢痕成纤维细胞胶原合成中的作用。 结果:①在增生性瘢痕的成纤维细胞可见1型受体和2型受体表达，阳性染色信号较强。放射性配体受体结合测定法显示在培养的增生性瘢痕的成纤维细胞有1型受体和2型受体，受体密度分别为(10.69±2.15)，(4.9±1.05) fmol/106个细胞。②在培养的人增生性瘢痕成纤维细胞，血管紧张素Ⅱ明显促进成纤维细胞胶原的合成，1型受体阻断剂Valsartan明显抑制血管紧张素Ⅱ的这种促进作用，2型受体拮抗剂PD123319明显增强血管紧张素Ⅱ的这种作用。 结论:在增生性瘢痕的成纤维细胞表达血管紧张素Ⅱ1型受体和2型受体，血管紧张素Ⅱ通过激活2种受体对成纤维细胞胶原的合成产生相反的作用，血管紧张素Ⅱ产生和受体表达比例的变化可能影响瘢痕的形成和成熟。     

血管紧张素Ⅱ对增生性瘢痕成纤维细胞PI3K/Akt信号通路的影响

目的 观察血管紧张素Ⅱ(angiotensin Ⅱ,Ang Ⅱ)对增生性瘢痕成纤维细胞磷脂酰肌醇-3激酶/蛋白激酶B(phosphoinositide 3-kinase/Akt,PI3K/Akt)信号通路的影响.方法 体外培养人增生性瘢痕成纤维细胞,用免疫荧光组织化学染色检测细胞Ang Ⅱ受体AT,和AT_2的表达.以PI3k活性测定法和Western Blotting法检测细胞PI3K的活性和Akt的磷酸化.结果 免疫荧光组织化学染色结果显示培养的增生性瘢痕成纤维细胞同表达AT_1和AT_2受体.Ang Ⅱ(10~(-9)～10~(-7)mol/L)刺激可增加细胞Akt的磷酸化和P13K的活性.AT_2受体拮抗剂PD1233191可显著增强AngⅡ诱导的细胞Akt磷酸化和PDK活性增加(P<0.05);AT_1受体拮抗剂Valsartan可显著抑制AngⅡ诱导的细胞Akt磷酸化和PDK活性增加(P<0.05).结论 Ang Ⅱ通过其受体AT_1和AT_2可调控增生性瘢痕成纤维细胞Akt磷酸化和PI3K的活性.     

The change of angiotensin Ⅱ production and its receptor expression during wound healing: possible role of angiotensin Ⅱ in wound healing

Objective This study was undertaken to observe the change in the local level of angiotensin Ⅱ (Ang Ⅱ) and the expression of its corresponding receptors AT1 and AT2 during wound healing, and explore the possible role of Ang Ⅱ in wound healing . Methods A model of full-thickness cutaneous wound was developed on the back of C57/BL6 mice. Specimens were taken from the wound of each mouse on the day 0, 1, 3, 5, 7, 9, 11, 13 and 15 after wounding. The change in the generation of Ang Ⅱ in wounded tissue during the healing process was detected with ELISA. The proliferation and the apoptosis of cells were detected by bromodeoxyuridine (Brdu) and terminal deoxyuncleotidyl transferase mediated deoxyuridine triphosphate nick end labeling (TUNEL) method in wounded skin during the healing process, respectively. The cellular localization and the mRNA level change of Ang Ⅱ receptors in wounded tissue during healing were detected with immunostaining and RT-PCR. Results Ang Ⅱ produced in wounded skin was increased in the first 7 days to reach the peak, and then gradually decreased during wound healing. BrdU labeling index was increased gradually in the first 7 days to reach the peak, and then gradually decreased during wound healing. The number of TUNEL-positive cells was increased slowly in the first 7 days after wounding. The increase in the number of TUNEL-positive cells was more markedly after epithelization of the wound. In normal mice, AT1 and AT2 receptor were found positively expressed in the whole epidermal layer, while positive expression was only found in the endothelial cells of the capillary vessels within the dermal layer, and positive expression was also found in appendages of the skin, i.e. hair follicle, sweat gland and sebaceous gland respectively. Positive staining signal of both AT1 and AT2 receptors were increased in the first 7 days to reach the peak, then gradually decreased. Expression of AT2R was increased again following the epithelization of wound. The result of RT-PCR showed that the expression of both AT1 and AT2 receptors was detectable, and AT1 receptor was increased in the first 7 days to the peak, and then gradually decreased during wound healing, while AT2 receptor expression reached its peak value on day 7, then gradually decreased, and increased again following the epithelization of wound. Conclusions These results indicate that Ang Ⅱ participate in wound repair and related to remolding in the late stage of wound healing through the change in production of angiotensin Ⅱ and expression of AT1 and AT2 receptors. AT1 receptor might be closely associated with cell proliferation,while AT2 receptor might play a role in cell apoptosis and remolding during wound healing.