雄性Akt2基因缺失小鼠生殖表型研究

目的通过对雄性Akt2基因敲除纯合子小鼠（Akt2-／-）及野生型小鼠（Akt2＋／＋）基础指标、血清糖脂及性激素水平的评估，探讨Akt2基因缺失对糖脂代谢及睾丸功能的影响。方法雄性Akt2＋／＋及Akt2-／-小鼠各15只，行口眼糖耐量（OGTT）实验（2mg／kg），予动力学实验，将纯合子和野生型小鼠分别随机分为2组，空白组和刺激组，刺激组予人绒毛膜促性腺激素（hCG）刺激4h，空白组予等体积的生理盐水刺激4h，检测各组小鼠体重、体内脂肪重量、血脂、空腹胰岛素及生殖激素水平。结果Akt2-／-小鼠同Akt2＋／＋小鼠相比，餐后随机血糖、0h、1h血糖均显著升高（P〈0．05）；睾丸重量显著增加（P〈0．01）。性激素检测发现Akt2-／-小鼠血清雄烯二酮（A2）（P〈0．01）和睾酮（T）（P〈0．05）显著升高；hCG刺激后，Akt2-／-与Akt2＋／＋小鼠的17-羟孕酮（17-OHP）、A2和T均显著升高，但Akt2＋／＋小鼠的T升高更明显。结论Akt2基因不仅影响糖代谢，同时影响睾丸功能，说明胰岛素调节糖代谢的关键信号分子可能对睾丸生殖功能同样具有重要的调节作用。hCG刺激后，同Akt2＋／＋小鼠相比，Akt2-／-小鼠A2和T升高的幅度较小，说明Akt2基因缺失使雄激素合成亢进，但降低了睾丸对hCG的敏感性。     

隐丹参酮对胰腺癌细胞生物学行为的影响及作用机制

背景与目的:胰腺癌是一种高度恶性的消化系统肿瘤,尽管目前针对胰腺癌的治疗方式在不断发展,患者预后仍然很差。隐丹参酮(CPT)是从植物丹参中提取的具有多种活性的单体,已被证实对宫颈癌、前列腺癌等有抗癌作用,但其对胰腺癌的作用尚不清楚,本研究通过体外实验探讨CPT对胰腺癌细胞生长和迁移的影响及相关机制,为相关的临床治疗药物研发提供理论和实验依据。方法:采用人胰腺癌BxPC-3细胞和SW1990细胞为研究对象,用3个浓度(10、20、40 μmol/L)的CPT处理该两种胰腺癌细胞不同时间(0、1、2、3 d)后,用CCK-8法检测CPT对细胞活力影响的浓度与时间效应;用以上3个浓度的CPT处理两种胰腺癌细胞24 h后,分别用克隆形成实验、划痕实验、Transwell实验检测对细胞克隆形成能力、迁移能力、侵袭能力的变化;用20 μmol/L CPT处理BxPC-3和SW1990细胞1、2、3 d后,用Western blot检测Akt、磷酸化Akt(p-Akt)以及上皮-间质转化(EMT)相关蛋白vimentin、E-cadherin与细胞周期相关蛋白CDK4、cyclin D1的表达。对照组细胞均只采用溶剂(DMSO)处理。结果:与各自对照组比较,CPT处理后的两种胰腺癌细胞的生长被明显抑制,且呈时间与浓度依赖性(均P0.05);划痕愈合程度、相对克隆形成率、侵袭细胞数均明显降低,且呈浓度依赖性(均P0.05);Akt、p-Akt、vimentin、E-cadherin、CDK4、cyclin D1蛋白的表达均明显下调,且呈时间依赖性(均P0.05)。结论:CPT能有效抑制胰腺癌细胞的生长和迁移,其作用机制可能与其下调Akt的表达,并进一步导致胰腺癌细胞生长周期阻滞及抑制EMT过程有关。     

隐丹参酮对前列腺癌DU145细胞中异黏蛋白表达的影响

目的:探讨隐丹参酮对前列腺癌DU145细胞增殖及细胞凋亡的作用,并初步探讨隐丹参酮对DU145细胞中异黏蛋白(MTDH)表达及下游PI3K/AKT信号通路的影响。方法:四氮唑蓝(MTT)比色法检测不同浓度隐丹参酮分别作用DU145细胞24、48、72 h后对细胞的生长抑制作用;原位末端转移酶标记(TUNEL)法检测细胞凋亡情况;Western印迹检测不同浓度隐丹参酮及作用不同时间对DU145细胞中MTDH蛋白的表达影响;RT-PCR技术检测隐丹参酮分别作用DU145细胞12、24、48 h后细胞中MTDH mRNA的表达情况;Western印迹检测隐丹参酮作用DU145细胞48 h后细胞中MTDH、AKT、p-AKT、Bcl-2蛋白的表达情况。结果:隐丹参酮能够明显抑制DU145细胞增殖,且抑制效应呈剂量和时间依赖性(P0.05);以10μmol/L隐丹参酮作用DU145细胞24、48、72 h后细胞凋亡率分别为(29.42±4.51)%、(55.07±5.67)%和(70.84±4.66)%,明显高于对照组(3.1±2.48)%(P0.05)。Western印迹和RT-PCR结果显示,隐丹参酮可在转录和翻译水平下调MTDH的表达(P0.05),抑制AKT信号通路和抗凋亡蛋白Bcl-2的表达(P0.05)。结论:隐丹参酮可抑制前列腺癌DU145细胞的增殖,促进细胞凋亡,其机制可能是通过下调MTDH表达,抑制其下游PI3K/AKT信号通路。     

丹参酮ⅡA与隐丹参酮混合物基于TGF-β1抑制人皮肤成纤维细胞的研究

目的：研究丹参酮ⅡA与隐丹参酮混合物对转化生长因子-β₁(Transforming growth factor-β₁,TGF-β₁)诱导人皮肤成纤维细胞(Humanskinfibroblasts,HSF)抑制瘢痕形成的影响及分子机制。方法：配制丹参酮ⅡA与隐丹参酮混合物(丹参酮ⅡA与隐丹参酮标准品按照1∶1的比例配置)溶液，采用TGF-β₁诱导HSF细胞增殖构建增生性瘢痕体外细胞模型；采用MTT法测定丹参酮ⅡA与隐丹参酮对HSF细胞增殖的影响；采用WesternBlot法检测HSF细胞中TGF-β₁/Smad信号通路下游信号分子p-Smad2、Smad3蛋白以及Survivin蛋白表达水平变化。结果：丹参酮ⅡA与隐丹参酮能剂量依赖地抑制HSF细胞的增殖，降低p-Smad2、Smad3蛋白和Survivin蛋白表达水平。结论：丹参酮ⅡA与隐丹参酮混合物可能通过下调p-Smad2、3和Survivin蛋白的水平，抑制HSF细胞的增殖，发挥抑制瘢痕的作用。     

脂肪抽吸术对胰岛素敏感性及脂质代谢的影响

目的了解脂肪抽吸术对胰岛素抵抗与脂质代谢的影响,并探讨其临床意义。方法对20例接受腹部脂肪抽吸术者术前及术后2个月的血清三酰甘油、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇,胰岛素敏感性进行测量并进行比较。结果术后与脂肪抽吸术前比较,术后胰岛素敏感性增强（P〈0.01）,血清总胆固醇与低密度脂蛋白胆固醇水平下降。结论腹部脂肪抽吸术在去除大量皮下脂肪的同时,对胰岛素抵抗、脂质代谢等心脑血管危险因素也有非常有益的影响。     

甲状腺激素对雄性小鼠生殖机能的影响

甲状腺激素对雄性小鼠生殖机能的影响杨秀萍吴群英张滨刘晓晴张玫玫曹绛雯董克奇高德伟本实验对甲状腺摘除术（ＴＥ）及正常小鼠服用甲状腺激素的方法，人为造成小鼠的甲减与甲亢状态，并观察成年及幼年鼠的生殖生理指标及血清睾酮（Ｔ）水平的变化，以比较甲亢与甲减对幼...     

创伤后胰岛素抵抗对机体代谢的影响

胰岛素抵抗(insulin resistance,IR)在创伤后非常普遍,是机体对创伤应激的一种反应,也是机体对胰岛素任何生理功能反应受损的表现。机体在创伤后通过神经内分泌的变化,分泌大量应激激素导致机体分解代谢增加、负氮平衡、瘦组织群减少和创口愈合不良;机体组织对胰岛素敏感性降低,表现为病理性高血糖、糖耐量下降、脂肪分解增加、高胰岛素血症等[1]。近年来,创伤后IR对机体内环境和代谢的影响越来越受到重视。一、创伤后IR及其机制IR是指胰岛素的外周靶组织(主要为骨骼肌、肝脏和脂肪组织)对内源性或外源性胰岛素的敏感性和反应性降低,导…     

胰岛素抵抗对尿毒症血脂代谢的影响

目的：探讨尿毒症患者胰岛素抵抗与血脂代谢紊乱的关系。方法：对58例尿毒症患者进行血脂测定，口服葡萄糖耐量试验和胰岛素释放试验，计算胰岛素敏感指数（ISI），机体糖代谢率（M），糖及胰岛素反应曲线下面积（AUCG，AUCINS），并进行统计学分析。结果：尿毒症患者餐后2h血糖及胰岛素水平，AUCG，AUCINS显著增,ISI,M显著降低，与正常对照组相比有显著差异（P＜0．05），尿毒症组TG，LDL－C明显增,HDL-C明显降低（P均＜0．05），与非胰岛素抵抗（NIR）组相比，胰岛素抵抗（IR）组LDL－C明显增,HDL-C明显降低（P＜0．05），直线相关分析LDL－C与ISI呈负相关(r=-0.43,P=0.001)，与AUCINS呈正相关（r=0.28,P=0.5)。结论：尿毒症患者存在IR及血脂代谢紊乱，IR可能是引起尿毒症脂质代谢紊乱的重要原因之一。     

铁调素敲除对雄性小鼠铁代谢及骨代谢影响的实验研究

目的 利用铁调素基因敲除雄性小鼠构建铁蓄积小鼠模型,观察小鼠铁代谢指标以及骨微结构的改变,探讨慢性铁蓄积对小鼠骨转换、氧化应激指标的动态作用。方法 根据基因鉴定将小鼠分为铁调素敲除组(KO组)与野生型组(WT组),正常饮食,分别在7、12、18月龄作为观察点,检测小鼠体重、胫骨铁含量,肝脏铁染色,分析小鼠股骨骨微结构,检测血清铁调素、铁蛋白、骨转换指标骨钙素(OCN)、I型胶原羧基末端肽(CTX)水平以及反映氧化应激水平的血清丙二醛(MDA)、超氧化物歧化酶(SOD)水平。结果 比较两组小鼠体重无明显差异,各时间点KO组小鼠的血清铁调素指标均显著低于WT组小鼠,KO组小鼠的血清铁蛋白、肝铁、骨铁含量均显著高于WT组小鼠;KO组小鼠纵向比较提示随着年龄增大,铁蓄积越来越明显。Micro-CT结果显示,与WT组小鼠比较,KO组松质骨BMD、Tb.Th、BV/TV、Tb.N、ConnD均显著下降(P<0.05),Tb.Sp、SMI显著升高(P<0.05)。KO组小鼠皮质骨面积低于WT组小鼠。横向同年龄比较,KO组小鼠的血清OCN、SOD水平均显著低于WT组小鼠(P<0.05...     

吗啡耐受对雄性大鼠生精功能影响的初步探讨

目的:研究在吗啡耐受模型中吗啡治疗疼痛时,对雄性大鼠的生殖能力造成的影响,并探讨其机制。方法:20只SD雄性大鼠,体重200~250 g,随机分为2组,Ⅰ组对照组,Ⅱ组吗啡耐受组,第一天行行为学测试,测定大鼠基础热缩足潜伏期(PWTL),然后皮下注射吗啡10 mg/kg,计算30 min时各组大鼠吗啡的MPE值。第2天,Ⅰ组注射生理盐水,每天2次;Ⅱ组皮下注射吗啡10 mg/kg,每天2次;Ⅰ组和Ⅱ组连续注射7 d,皮下注射时间为每天8:00和17:00,第7天进行行为学测试,方法同第1天。行为学检测完毕立即处死大鼠,留取附睾,对附睾尾进行精子计数;睾丸,采用免疫组织化学检测Bax和Caspase-3的表达。结果:第1天两组大鼠基础热痛阈和MPE值无明显差异。第7天两组大鼠的基础热痛阈无明显差异,但与Ⅰ组相比,Ⅱ组的MPE值降低(P0.05);说明吗啡耐受模型制作成功,精子计数显示,吗啡耐受组精子相对数目明显减少(P0.05),睾丸组织切片中,吗啡组Bax和Caspase-3的阳性表达都高于对照组。结论:吗啡耐受模型中,雄性SD大鼠的精子相对数目减少,吗啡组Bax和Caspase-3的阳性表达都高于对照组,由此推测,吗啡耐受可能通过上调Bax和Caspase-3增加雄性大鼠生殖系统的细胞凋亡,影响精子浓度。     

PI3KCA及Akt1在人胆管腺癌中的表达及其与临床病理特征的关系

目的探讨PI3KCA与Akt1表达与胆管癌病理特征的关系及其对胆管癌预后的预测价值。方法采用免疫组化检测PI3KCA、Akt1在人胆管腺癌及癌旁正常胆管组织中的表达;采用Western blotting法及(q RT)-PCR法检测新鲜人胆管腺癌及癌旁正常胆管组织中PI3KCA、Akt1在蛋白及m RNA水平表达。结果PI3KCA和Akt1表达于胆管腺癌细胞质,在癌旁正常胆管组织中PI3KCA、Akt1无表达或轻度表达,差异有统计学意义(x2=2.659,P0.05;x2=1.353,P0.05);PI3KCA高表达与肿瘤直径、肿瘤TNM分期、淋巴结转移有正相关性(x2=3.526,P0.05;x2=5.295,P0.05;x2=8.174,P0.05);Akt1高表达与肿瘤直径、肿瘤TNM分期、淋巴结转移有正相关性(x2=7.102,P0.05;x2=3.142,P0.05;x2=5.491,P0.05);Spearman rank相关分析结果显示,PI3KCA、Akt1呈统计学正相关性(r=0.376,P0.05);Western blotting显示,PI3KCA、Akt1蛋白表达在胆管癌组织中明显高于配对的癌旁正常组织(t=2.142,P0.05;t=3.549,P0.05);PI3KCA、Akt1在胆管腺癌组织中m RNA表达明显高于配对的癌旁正常组织(t=3.276,P0.05;t=4.901,P0.05)。结论 PI3KCA及Akt1在人胆管腺癌中高表达,其表达上调提示胆管癌预后不良,PI3KCA可能通过PI3K/Akt信号通路调节胆管癌的恶性行为。     

Development of polycystic ovary syndrome: involvement of genetic and environmental factors

We have recently proposed that polycystic ovary syndrome (PCOS) has its origin in fetal life. This hypothesis is based on data from animal models (rhesus monkey or sheep that have been exposed prenatally to high doses of androgen) and is supported by clinical studies. It is suggested that, in human females, exposure to excess androgen, at any stage from fetal development of the ovary to the onset of puberty, leads to many of the characteristic features of PCOS, including abnormalities of luteinizing hormone secretion and insulin resistance. It is likely that, in humans with PCOS, the development of the PCOS phenotype results primarily from a genetic predisposition for the fetal ovary to hypersecrete androgen. At present, it is unclear whether the maternal environment directly influences the development of PCOS in the offspring. Maternal androgen excess is unlikely to affect the fetus, because the placenta presents an effective barrier, but metabolic disturbances during pregnancy could affect development of the syndrome in the fetus. In postnatal life, the natural history of PCOS can be further modified by factors affecting insulin secretion and/or action, most importantly, nutrition. We now have evidence for a disorder of early follicular development in the polycystic ovary that is consistent with an increased population of primordial follicles in the fetal ovary. It remains to be determined whether this phenomenon is the cause or the effect of increased exposure to androgen within the ovary. PCOS is the commonest endocrine disorder in women. It is not only a very prevalent cause of anovulatory infertility, menstrual disturbances and hirsutism, but it is also a major risk factor for the development of type 2 diabetes mellitus in later life. The aetiology of the syndrome remains uncertain but there is increasing evidence for a genetic basis. PCOS very often becomes clinically manifest during adolescence with maturation of the hypothalamic-pituitary-ovarian axis but the genesis of the syndrome may be during very early development - perhaps even in utero. In this review, this hypothesis is explored in the light of clinical, biochemical and genetic research.     

Modulation of FAK, Akt, and p53 by stress release of the fibroblast-populated collagen matrix

BACKGROUND: Fibroblast survival in a three-dimensional collagen matrix is dependent in part upon the rigid anchorage of the matrix to tissue culture plastic. We hypothesized that focal adhesion kinase (FAK) and protein kinase B (Akt) would be activated and that the p53 level would be low in the rigidly anchored (attached) collagen matrix; loss of anchorage (detachment) was hypothesized to have the opposite effects. MATERIALS AND METHODS: Human foreskin fibroblasts were cultured in attached bovine collagen matrices for 48 h before detachment as free-floating matrices. At various time points postrelease, matrix lysates were blotted for the proteins of interest, and the terminal deoxynucleotidyltransferase-mediated dUTP nick-end label assay was performed on both whole matrices and cytospin preparations. Irradiated monolayer fibroblasts were used as positive controls for the amount of p53 protein. RESULTS: Terminal deoxynucleotidyltransferase-mediated dUTP nick-end label positivity in attached versus detached matrices (at 24 h post detachment) was 0.7 +/- 03 versus 5.3 +/- 1.7% (P < 0.05, unpaired t test). FAK and Akt were phosphorylated (activated) in the attached matrix; there was a near complete of loss of both activated forms within 4 h of matrix detachment. Irradiated monolayer fibroblasts had increased levels of p53, mdm2, and p21. In contrast, the p53, mdm2, and p21 levels were just at the level of detection in the attached matrix, but were induced 5- to 10-fold within 2-4 h after matrix detachment. CONCLUSIONS: FAK and Akt are activated in the attached fibroblast-populated collagen matrix whereas the p53 level is relatively low; matrix detachment downregulates FAK and Akt activity and induces p53. The state of mechanical anchorage of the collagen matrix regulates the survival of embedded fibroblasts through a mechanism which may involve FAK.     

A prospective, randomized pilot study evaluating the effects of metformin and lifestyle intervention on patients with prostate cancer receiving androgen deprivation therapy

Study Type – Therapy (RCT) Level of Evidence 1b What's known on the subject? and What does the study add? Men with prostate cancer have higher rates of non‐cancer mortality and CV morbidity and some of that excess risk has been attributed to the treatment they receive. ADT is an established treatment option for men with locally‐advanced and metastatic prostate cancer and, although it has been shown to confer a disease‐free survival advantage, it has also been associated with an increased incidence of CV disease and the metabolic syndrome (characterized by a cluster of CV risk factors, including insulin resistance). The benefits of the insulin sensitizer metformin and lifestyle intervention for reducing the incidence of metabolic syndrome have been shown in patients with impaired glucose tolerance. At the time of writing, the present study is the first to use metformin and lifestyle intervention in men with prostate cancer with the aim of reducing the risk of developing ADT‐related CV morbidity and the metabolic syndrome. The study shows that lifestyle changes and metformin may indeed reduce the complications of androgen suppression in these men. Although further investigations are needed to establish which of the two interventions may be most beneficial, the favourable effects of a combination of these interventions on patients' quality of life and the potential for improved overall survival are of clinical significance.

OBJECTIVE

• ? To investigate the effects of metformin and lifestyle changes on the development of androgen deprivation therapy (ADT)‐related metabolic syndrome.

PATIENTS AND METHODS

• ? Men with prostate cancer due to receive ADT were recruited and randomized.
• ? Controls received ADT alone.
• ? Men in the intervention arm received ADT with 6 months of metformin, a low glycaemic index diet and an exercise programme.
• ? All patients were investigated pretreatment and at 6 months for the metabolic syndrome, as well as for related biochemical and physical parameters.

RESULTS

• ? In total, 40 men were recruited and randomized (20 to each arm).
• ? After 6 months, significant improvements in abdominal girth (P= 0.05), weight (P < 0.001), body mass index (P < 0.001) and systolic blood pressure (P= 0.01) were seen in the intervention arm compared to controls.
• ? Biochemical markers of insulin resistance did not differ significantly.

CONCLUSIONS

• ? The present study shows the potential benefits of metformin and lifestyle changes in ADT‐treated men.
• ? Further studies will aim to determine which intervention is most important, and may show that overall survival can be improved.

     

Impact of insulin resistance,insulin and adiponectin on kidney stones in the Japanese population

Objectives: It has been reported that kidney stones are linked to metabolic syndrome (MetS), which is characterized by insulin resistance. The aim of the present study was to examine the association of insulin resistance, insulin and adiponectin with kidney stones in a Japanese population. Methods: From February 2007 to March 2008, 1036 (529 men and 507 women) apparently healthy Japanese subjects, aged 35–79 years, were analyzed. Weight, height, waist circumference and blood pressure were measured. Overnight fasting blood was collected to measure insulin and adiponectin levels. Homeostasis model assessment of insulin resistance (HOMA‐IR) was calculated to assess insulin resistance. Logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence intervals for a self‐reported history of kidney stones across tertiles of HOMA‐IR, insulin and adiponectin. Results: Of the participants, 84 men (15.6%) and 35 women (6.9%) had a history of kidney stones. Age, body mass index, waist circumference, systolic and diastolic blood pressures, HOMA‐IR and insulin were significantly higher in women with than in women without kidney stones. There was no difference in adiponectin level between subjects with and without a history of kidney stones in either sex. Furthermore, a significant positive trend was observed in the age‐adjusted OR for a history of kidney stones across insulin tertiles (P‐value for trend = 0.04) in women. Conclusions: For Japanese women, HOMA‐IR and insulin are associated with a history of kidney stones. The findings suggest that MetS components could increase the risk of kidney stones through subclinical hyperinsulinemia and insulin resistance.     

Insulin action on glucose and protein metabolism during L-carnitine supplementation in maintenance haemodialysis patients.

BACKGROUND: Impaired protein anabolism and insulin resistance are characteristic features of maintenance haemodialysis patients. We have used a randomised, matched-paired, double-blind, placebo-controlled experimental design to determine the capability of intravenous L-carnitine supplementation to modify insulin resistance and protein catabolism in non-diabetic patients with end-stage renal disease (ESRD) undergoing chronic haemodialysis treatment. METHODS: L-carnitine (20 mg x kg(-1)) (n = 9) or placebo (n = 10) were given intravenously at the end of seven consecutive dialysis sessions. Whole-body protein and glucose metabolism were assessed on interdialytic days by the L[1-(13)C]leucine and the [2,2-(2)H(2)]glucose kinetic models in the postabsorptive state and during euglicemic hyperinsulinemic clamp studies at baseline and at the end of the treatment period. RESULTS: L-carnitine supplementation was associated with lower (P < 0.05) rates of leucine oxidation (-11 +/- 12%) and appearance from proteolysis (-6 +/- 2%) during the clamp studies than after placebo supplementation. The rates of glucose appearance in the postabsorptive state did not change significantly in the patients receiving L-carnitine treatment. Insulin-mediated glucose disappearance was improved by L-carnitine only in those patients (n = 5) (+18 +/- 3%, P < 0.05 vs placebo group, n = 5) with greater baseline insulin resistance, selected according to the median value of insulin sensitivity before treatment. CONCLUSIONS: L-carnitine supplementation was associated with protein-sparing effects in maintenance haemodialysis patients during hyperinsulinemia.     

烧伤血清作用下心肌细胞蛋白激酶B和p38丝裂原活化蛋白激酶通路的交叉对话研究

目的 了解在烧伤血清刺激下大鼠心肌细胞内是否存在磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(Akt)与p38丝裂原活化蛋白激酶(p38MAPK,以下简称p38)信号通路的交叉对话,探讨此二通路在烧伤后心肌细胞损伤中的作用. 方法建立烧伤血清刺激下的大鼠心肌细胞模型.(1)检测体积分数10%的烧伤血清刺激不同时间后,心肌细胞内磷酸化p38(p-p38)和磷酸化Akt(p-Akt)的表达水平.(2)检测在不同体积分数(5%、10%、20%)的烧伤血清或体积分数10%烧伤血清+胰岛素(1×10-6、1×10-7、1×10-8mol/L)作用下,心肌细胞内p-p38和p-Akt的表达水平,并测定细胞培养上清液中肌酸激酶(CK)的含量.(3)采用p38MAPK通路抑制剂SB203580、PI3K/Akt通路抑制剂LY294002进行阻断实验,测定心肌细胞内p-p38和p-Akt的表达水平及细胞培养上清液中CK的含量. 结果 (1)体积分数10%烧伤血清作用1、3、6、12、24 h时,心肌细胞p-p38水平分别为4.0±0.8、3.6±0.8、5.1±1.6、2.4±0.5、3.0±0.6,较作用0 h时(加入血清后即刻)的水平(1.0)明显增高(P<0.01);而p-Akt表达水平分别为0.15±0.07、0.64±0.10、0.26±0.08、0.38±0.11、0.59±0.13,较作用0 h时水平(1.00)明显降低(P<0.01).(2)不同浓度烧伤血清或烧伤血清+胰岛素作用下,p-p38和p-Akt的表达水平呈相反变化趋势;心肌细胞CK的释放量随烧伤血清浓度升高而增高,胰岛素对此有明显的抑制作用(P<0.05或P<0.01).(3)LY294002能够升高烧伤血清导致的低P-p38水平,抵消胰岛素的保护作用(P<0.01);SB203580能使烧伤血清所致的低p-Akt水平得以回升(P<0.01),抑制烧伤血清引起的CK释放. 结论烧伤血清作用下的心肌细胞存在PI3K/Akt和p38信号通路的交叉对话,并可能对心肌细胞产生调控作用.