胎兔伤口无瘢痕愈合的形态学和胶原构成研究

目的：探讨胎兔伤口无瘢痕愈合的可能机理及条件。方法：用22－23d的孕兔建立胎兔伤口无瘢痕愈合的动物模型,并与孕兔、成年兔伤口愈合进行比较,对各组兔皮肤切口组织进行光镜和透射电镜检查,胶原含量测定（羟脯氨酸法）及分型。结果：①胎兔切口无急性炎症反应,成纤维细胞（FB）出现早,伤口无瘢痕一期愈合。②胎兔伤口中胶原含量及构成变化不显著;孕兔、成年兔胶原在术后7d时升高（P＜0．05）。结论：无急性炎症反应、皮肤中的FB及胶原构成是胎兔伤口无瘢痕愈合的重要因素。     

胎兔皮肤伤口中糖胺多糖及透明质酸含量分析

目的探讨胎兔皮肤伤口无瘢痕愈合机理。方法 取胎兔,孕兔,成年兔切口及其周围组织,用阿利新蓝比色法,醋酸纤维素膜电脉分离法测定糖胺多糖（GAG）和透明质酸（HA）含量。结果 （1）胎兔正常皮肤（GAG及HA的含量均明显高于孕兔及成年兔（P＜0．01）,手术区,胎兔,孕兔,成年兔在术后3天时GAG及HA均升高（P＜0．05）。但术后第7天,胎兔GAG含量仍维持在高水平,而孕兔及成年兔其含量下降到接近正常水平,。结论 高浓度的HA在胎兔伤口间质的持续存在对胎兔伤口无瘢痕愈合起很重要的作用。     

透明质酸含量在兔正常皮肤及皮肤创伤愈合过程的变化

目的　分析透明质酸在创伤愈合过程中的含量变化以及胎儿型愈合和成人型愈合的机理。方法　通过胎兔创伤模型及皮肤均化的方法，提取游离及结合的透明质酸（ＨＡ） ，应用透明质酸结合蛋白（ ＨＡＢＰ） 技术，对胚胎兔、成年兔皮肤在正常及创伤愈合过程中用放射免疫法测定游离、结合及ＨＡ 的总量。结果　⑴不同孕期正常胎兔皮肤的游离ＨＡ 及ＨＡ 总量的差异均无显著意义，结合ＨＡ 有显著的波动，而且均比正常成兔增高（ Ｐ＜ ０ ．０１） ；⑵胎兔皮肤创伤后不同愈合时间的游离ＨＡ 及ＨＡ 总量的差异均无显著意义，结合ＨＡ 的组成亦有显著变化；⑶创伤胎兔与正常胎兔相比，各组分ＨＡ 均增高（ Ｐ＜ ０ ．０５） ；⑷创伤成年兔游离ＨＡ 及ＨＡ 总量均比正常成年兔显著增高（ Ｐ＜ ０ ．０１） ，而在创伤成年兔内部游离ＨＡ 及ＨＡ 总量呈“山峰型”变化；⑸胎兔、成年兔皮肤创伤后对应比较发现，ＨＡ 总量均为胎兔高（ Ｐ＜ ０ ．０１） ，而游离ＨＡ 则第２ 、３ 天差异无显著意义。结论　ＨＡ 的增高是胎儿型愈合不可缺少的内部机制，其中游离ＨＡ 起主导作用，但结合ＨＡ 随孕期的延长以及在创伤后不同愈合时间所发生的显著变化，对于临床控制瘢痕形成具有很重要的意义     

胚胎兔、成兔皮肤在正常发育及创伤愈合过程中IgG的表达

目的 分析胚胎兔，成兔胚皮肤在便伤愈合过程中IgG表达的差异，为胎儿型及成人型愈合机制的研究提供依据。方法 在建立胎兔皮肤创伤模型的基础上，采用皮肤均化的方法，提取正常及创伤组织中的免疫球蛋白IgG，用双抗体夹心ELISA法进行含量测定。结果 随正常胎兔（孕23－28天）孕期的延长，皮肤中IgG有合成增加的趋势，而正常成免皮肤的IgG含量显著高于胎兔（P＜0．01）；胎兔皮肤创伤后不同时间（1－6d)的IgG含量与对应的正常胎兔（孕23－28天）相比，只伤后第1，2天增高（P＜0．01），而不同孕期的创伤胎兔之间差异无显著意义。成兔皮肤创伤后从第2天起IgG合成量明显高于正常成兔（P＜0．01），并呈现明显的上升趋势，对胎，成兔皮肤创伤后IgG变化趋势的动态发现胎兔呈平坦线性，成兔呈上升线性。结论 在胚胎发育成熟的过程中，免疫系统日臻完善，虽然IgG在较低水平，但在创伤后仍表现出一定的免疫反应，而成兔在创伤后却表现出强烈的免疫反应，不仅含量高而且趋势显著，免疫反应的不同是胎儿愈合与成人型愈合的本质差别之一。     

一氧化氮在成兔与胚胎兔创面愈合过程中含量的比较

目的:分析胚胎无瘢痕愈合的潜在原因,研究NO(一氧化氮)在成人型和胚胎型愈合过程中的差别.方法:在已建立的胎兔创伤模型的基础上,用一氧化氮酶法试剂盒检测胚胎兔和成兔皮肤匀浆液中NO的含量,并对结果进行比较.结果:①正常胎兔不同孕期皮肤中NO含量无差别.②正常胎兔皮肤中NO含量高于正常成兔皮肤中NO含量(P＜0.01).③创伤胎兔皮肤中NO含量高于正常胎兔皮肤中NO含量(P＜0.01).④创伤成兔皮肤中NO含量高于正常成兔皮肤中NO含量(P＜0.01).⑤创伤胎兔皮肤中NO含量高于创伤成兔皮肤中NO含量(P＜0.01).结论:NO参与了胚胎和成年动物的创面愈合过程,并在两种愈合过程中存在差别.     

胎兔皮肤无瘢痕愈合相关蛋白的筛选与初步分析

目的：筛选胎兔皮肤组织无瘢痕愈合相关蛋白，并初步分析其在无瘢痕愈合过程中的作用。方法：建立胎兔背部切割伤模型，运用蛋白质组双向电泳技术筛选胎兔皮肤伤后差异表达的蛋白质，并进行质谱和数据库检索分析。结果：筛选出20个在伤后胎兔皮肤组织中特异高表达的蛋白质点，经过质谱和数据库检索分析后确定：伴侣素或线粒体蛋白P1前体、弹性蛋白（Vimentin，Vim）、微管蛋白β多肽、核不均一核糖核蛋白H（异质性胞核核糖核蛋白H）、α-烯醇酶（α-磷酸丙酮酸水合酶）等无瘢痕愈合相关蛋白在胎兔皮肤伤后表达增加。结论：上述无瘢痕愈合相关蛋白可能通过对基因转录和翻译的调控，促进胶原蛋白等的合成和正确的折叠、装配，以及促进细胞的增殖、分化和发育等，促进胎兔皮肤创伤的修复，参与其无瘢痕愈合过程。     

一氧化氮在成兔与胚胎兔创面愈合过程中含量的比较

目的 :分析胚胎无瘢痕愈合的潜在原因 ,研究NO(一氧化氮 )在成人型和胚胎型愈合过程中的差别。方法 :在已建立的胎兔创伤模型的基础上 ,用一氧化氮酶法试剂盒检测胚胎兔和成兔皮肤匀浆液中NO的含量 ,并对结果进行比较。结果 :①正常胎兔不同孕期皮肤中NO含量无差别。②正常胎兔皮肤中NO含量高于正常成兔皮肤中NO含量 (P <0 .0 1)。③创伤胎兔皮肤中NO含量高于正常胎兔皮肤中NO含量 (P <0 .0 1)。④创伤成兔皮肤中NO含量高于正常成兔皮肤中NO含量 (P <0 .0 1)。⑤创伤胎兔皮肤中NO含量高于创伤成兔皮肤中NO含量 (P <0 .0 1)。结论 :NO参与了胚胎和成年动物的创面愈合过程 ,并在两种愈合过程中存在差别     

IFN-γ抑制兔耳皮肤伤口愈合和瘢痕增生中蛋白激酶C的活性变化

目的观察IFN-γ抑制兔耳伤口愈合和瘢痕形成中肉芽组织和瘢痕组织中蛋白激酶C（Protein Kinase C，PKC）活性的变化，探讨PKC的信号作用。方法兔耳伤口或瘢痕组织内使用IFN-γ，用^32P掺入底物法测定伤后3、6d、上皮化时（11～16d），上皮化后14、30和45d瘢痕组织的PKC活性，并观察上皮化时间和瘢痕变化。结果肉芽组织、周边组织和瘢痕组织的PKC活性伤后持续升高（P〈0．01），IFN-γ没有改变PKC活性（P〉0．05，）但延迟创面愈合约1．5d（P〈0．01），并抑制瘢痕增生（P〈0．05）。结论IFN-γ抑制伤口愈合和瘢痕增生的作用不经PKC介导；PKC活化与伤口愈合和瘢痕增生有关。     

胚胎兔和成年兔伤口愈合中肌成纤维细胞的表达

胚胎动物与成年动物的创伤愈合存在差别 ,表现在炎症反应轻、创面不收缩和无瘢痕形成[1,2 ] 。本实验在光镜和电镜下观察胚胎兔和成年兔伤口愈合过程中肌成纤维细胞(ｍｙｏｆｉｂｒｏｂｌａｓｔ,ＭＦＢ)的表达 ,以期探讨胎兔伤口不收缩的原因以及胎兔无瘢痕愈合的机制。材　料　和　方　法1.动物模型及分组 :选择怀孕 2 3ｄ的日本大耳白兔 6只 ,随机分为两组 ,每组 3只 ,每只孕兔取两只胎兔做创伤 ,分别于创伤后 3、6ｄ行剖宫产手术取出创伤胎兔 ,在取出创伤胎兔的同时 ,每只孕兔还剖取两只正常胎兔作对照。另取普通成年日本大耳白兔 12只 ,…     

人胚胎无瘢痕愈合模型的建立及组织学初步观察

创面愈合后瘢痕形成一直是困扰整形外科医师的临床难题 ,孕中期胎儿皮肤创面愈合后无瘢痕形成 ,成为人们期望的理想愈合方式[1 ] ,我们将孕中期人胎儿皮肤异种移植至裸鼠的皮下 ,建立人胎儿无瘢痕愈合的模型 ,并对其愈合过程进行了组织学观察 ,以期为人胎儿无瘢痕愈合机制的研究提供一定依据。1　材料和方法1 1　材料1 1 1　动物　雌性的成年裸鼠 (ＢＡＬＢ ｃ) 4 0只 ,6～ 7周龄 ,体重 (2 0± 1)ｇ,由上海医药工业研究院动物房提供。裸鼠随机分成 8组 ,无菌饲料饲养于 2 3℃无菌环境中。1 1 2　人胎儿皮肤　孕龄为 2 0～ 2 4周的正常健康孕…     

胎儿及成人皮肤创面愈合过程中PDGF和EGF表达的对比性研究

目的 探讨人胎儿和成人皮肤及其创面愈合过程中PDGF和EGF的表达及意义。方法 利用已建立的人胎儿无瘢痕愈合动物模型，获取相应标本，结合临床所取成人皮肤标本，采用免疫组化染色方法，观察PDGF，EGF的表达情况。结果 ①正常胎儿皮肤中未见明显的PDGF阳性染色；创伤后12h、1d的胎儿表皮及真皮浅层可见PDGF的弱阳性表达；创伤后3d、1周的胎儿皮肤中PDGF的表达呈阴性；正常成人皮肤可在成纤维细胞，巨噬细胞及毛细血管见到阳性表达；创伤后表达加强；②正常胎儿皮肤表皮全层和毛囊，皮脂腺及汗腺细胞可见EGF的阳性表达；创伤后的胎儿皮肤中EGF的表达未见到明显变化；正常成人皮肤可见表皮基底层有中度阳性表达，毛囊，汗腺细胞也可见到轻度表达，创伤后表达有所减弱。结论 生长因子在胎儿和成人皮肤创面愈合过程中的差异表达可能是胎儿无瘢痕愈合的重要原因之一。     

外用中药对兔创面表皮细胞生长因子的影响

目的 :探讨外用中药对白兔创面愈合不同时期肉芽组织中表皮细胞生长因子 (EGF)的影响与创面愈合之间的关系。方法 :采用手术方法造成背部的深创面白兔 85只。随机分成愈创膜组、生肌愈皮膏组和凡士林组。 3组创面分别应用相应药物治疗。分别于术后第 3、5、7、11、15天 ,以放射免疫法测定创面肉芽组织EGF含量。结果 :术后第 3、5、7天 ,2个中药组创面肉芽组织中EGF含量均高于凡士林组 (P <0 .0 1)。且 2个中药组第 5天时EGF含量均达到整个愈合过程中的峰值 ,在第 7天时仍保持高浓度。而凡士林组第 7天时才达到高峰。第 11、15天时 3组EGF含量逐渐减少 ,各时间点 2个中药组间比较差异无显著性意义 (P >0 .0 5 )。结论 :愈创膜及生肌愈皮膏均能增加早、中期白兔创面肉芽组织的EGF含量 ,从而加快创面的愈合。     

Oxidant and antioxidant events during epidermal growth factor therapy to cutaneous wound healing in rats

Cutaneous wound healing is a highly complex process, which includes inflammation, cell proliferation, matrix deposition and remodelling phases. Various growth factors, like epidermal growth factor (EGF), play an important role during wound healing. However, little is known about relationship between EGF and oxidant-antioxidant events in cutaneous wound healing models. Thus we planned to evaluate the connection between EGF therapy and oxidative stress in dermal tissue followed by wounding. Fifty-four adult male Wistar-albino rats were randomly divided into three groups: control, untreated and topical EGF administrated group. A linear full-thickness excision of 40 mm in length on both sides of spinal cord was made on the back of each rat and sutured under anaesthesia and sterile conditions. Excision was closed with 4/0 atraumatic silk suture. EGF solution was freshly prepared at 10 ng/ml dose in thilotears gel under aseptic conditions. Following the surgery, 1 ml of EGF solution was administered to wound strips one time in everyday. The animals were euthanised and wound tissues were collected on days 1, 5, 7 and 14. Thiobarbituric acid reactive substans (TBARS), glutathione (GSH), reactive nitrogen oxide species (NOx), ascorbic acid levels and superoxide dismutase activity were measured spectrophotometrically. TBARS levels decreased and NOx levels increased on day 5 after operation, and GSH levels were increased on day 14 in EGF administered group compared with untreated group. Our data showed that EGF may act like an antioxidant by scavenging toxic oxidation products in wound tissue. In addition, it may contribute healing of the wound tissue in earlier stages and suggest a potential effective role for antioxidant therapies, especially until day 5.     

Ultrastructural analysis of fetal rabbit wounds

Fetal wound healing proceeds rapidly with minimal inflammation and fibroplasia and little or no scar formation. These observations have led to the hypothesis that fetal wound healing more closely resembles regeneration rather than adult wound repair. To test this hypothesis, this study used ultrastructural analysis of fetal and adult fibroblasts and collagen to gain greater insight into differences in the healing processes. Full-thickness, primarily closed linear incisions were created dorsally on 24-day gestational age fetal rabbits (n = 9). The fetuses were killed 5 days later, and the wounds were excised and evaluated with transmission electron microscopy. Similarly, uninjured fetal skin of the same gestational age was obtained and analyzed. Adult rabbit dermal wounds were analyzed after 8 days of healing. Resting adult dermal fibroblasts had features of quiescent, inactive cells, whereas adult wound fibroblasts were highly active and filled with secretory vesicles. In contrast, both fetal normal dermal and wound fibroblasts appeared highly active and contained numerous secretory vesicles. In the adult wound, collagen fibril diameter was only 45% of the diameter of normal dermal collagen. However, fetal wound collagen fibrils were basically the same as normal dermal collagen, having a diameter that was 82% of the size of dermal collagen. These observations suggest that fetal wound fibroblasts do not require activation from an inactivated state and that fetal wound collagen deposition undergoes more rapid organization and maturation. These findings have significance in extending our understanding of the rapidity and functional superiority of fetal wound healing compared with adult wound healing.     

Effect of substance P released from peripheral nerve ending on endogenous expression of epidermal growth factor and its receptor in wound healing

Objective: To explore the relationship between substance P (SP) released from peripheral nerve endings and the expression of epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR) during wound bealing. Methods: Fifty Wistar rats were randomly divided into 2 groups, injury group and capsaicin group. In the injury group, a full-thickness skin wound on the back of the rat was taken. The wound edge and granulation tissues were taken on the 1st, 3rd, 6th, 9th, 12th days after injury, respectively. In the capsaicin group, capsaicin was injected subcutaneously on the back of the rats to destroy the sensory nerve to prevent the secretion of SP, then a wound and sample was made in the same way.Immunohistochemistry and in situ hybridization were employed to detect the expression of SP, EGF/EGFR, and EGF mRNA/EGFR mRNA in the granulation tissues.Results: In the injury group,immunohistochemical stain of SP and EGF/EGFR was located on the hair follicles and sebaceous glands at the 1st day. And the stain of SP was obvious at the 3rd day in the granulation tissues, then decreased gradually. EGF/EGFR was at low level at the 3rd day, then increased gradually and reached the peak at the 9th day, then declined. In the capsaicin group, the stain of SP and EGF/EGFR was faint and without obvious change during the wound healing process. The tendency of the EGF mRNA/EGFR mRNA expression was similar to that of EGF/EGFR. Conclusions: During wound healing, SP may promote the healing process by affecting the expression of EGF/EGFR in the erunuation tissues.     

胎儿和成人皮肤及其创面愈合过程中碱性成纤维细胞生长因子的表达及意义

目的　探讨胎儿和成人皮肤及其创面愈合过程中碱性成纤维细胞生长因子 (b FGF)的表达及其意义。方法　将孕龄 2 0～ 2 4周胎儿皮肤移植至 BAL B/ C裸鼠背部皮下 ,皮片成活后制造创面 ,建立胎儿无瘢痕愈合动物模型 ,定期获取相应标本。对临床所取正常成人皮肤及创面愈合皮肤标本 ,采用免疫组织化学染色方法 ,观察 b FGF的表达情况。　结果　正常胎儿皮肤及创伤后胎儿皮肤中均未见明显的 b FGF阳性表达。正常成人皮肤中血管周围可见阳性表达 ;创伤后成人皮肤也可见阳性表达 ,尤其成纤维细胞和血管内皮细胞创伤后表达明显增强。高倍镜视野随机观察计数b FGF阳性表达细胞数 ,正常胎儿皮肤为 2 .1± 0 .1,创伤后 12小时 ,1、3天和 1周胎儿皮肤分别为 2 .2± 0 .1、2 .1± 0 .3、2 .1± 0 .3和 2 .0± 0 .1;正常成人皮肤为 2 3.2± 4 .2 ,创伤后成人皮肤为 4 0 .5± 3.6 ,胎儿正常皮肤和创伤皮肤 b FGF表达与正常成人皮肤和创伤后皮肤 b FGF表达比较 ,差异有统计学意义 (P<0 .0 1)。　结论　 b FGF的阴性表达可能是胎儿皮肤无瘢痕愈合的重要原因之一。     

Wound healing in a fetal,adult, and scar tissue model: A comparative study

Early gestation fetal wounds heal without scar formation. Understanding the mechanism of this scarless healing may lead to new therapeutic strategies for improving adult wound healing. The aims of this study were to develop a human fetal wound model in which fetal healing can be studied and to compare this model with a human adult and scar tissue model. A burn wound (10 × 2 mm) was made in human ex vivo fetal, adult, and scar tissue under controlled and standardized conditions. Subsequently, the skin samples were cultured for 7, 14, and 21 days. Cells in the skin samples maintained their viability during the 21‐day culture period. Already after 7 days, a significantly higher median percentage of wound closure was achieved in the fetal skin model vs. the adult and scar tissue model (74% vs. 28 and 29%, respectively, p<0.05). After 21 days of culture, only fetal wounds were completely reepithelialized. Fibroblasts migrated into the wounded dermis of all three wound models during culture, but more fibroblasts were present earlier in the wound area of the fetal skin model. The fast reepithelialization and prompt presence of many fibroblasts in the fetal model suggest that rapid healing might play a role in scarless healing.