1、Chapter 3,血浆蛋白质以及非蛋白含氮化合物的代谢紊乱Metabolic disorders of plasma protein and NPN,广东医学院临床生物化学教研室Department of clinical biochemistryOf Guangdong medical college,目的： 学习并掌握血浆蛋白质、氨基酸、核苷酸的代谢紊乱及临床检测,主要内容：一、血浆蛋白质（一）血浆蛋白质的功能及分类（二）血浆蛋白质的电泳（三）血浆蛋白质主要组分的生化检验*（四）急性时相反应蛋白*二、氨基酸代谢紊乱（三）主要氨基酸代谢紊乱的生化检验三、核苷酸代谢紊乱（一）嘌呤核苷酸代谢紊
2、乱（二）嘧啶核苷酸代谢紊乱四、检测方法评价（补）,1 Plasma Protein血浆蛋白质,1.1 Function and classify of plasma protein 血浆蛋白质的功能和分类1.1.1血浆蛋白质的功能Q:What functions do plasma proteins have?,http:/en.wikipedia.org/wiki/Blood_proteinsPlasma proteins, also called serum proteins, are proteins found in blood plasma. The total protein in
3、 blood is 70g/L, which in total makes 7% of total body weight.They serve many different functions, includingcirculatory循环的 transport运输 molecules for lipids, hormones, vitamins and metals金属.enzymes酶, complement components补体成分, protease inhibitors蛋白酶抑制剂, and kinin precursors激肽前体regulation of a cellula
4、r activity and functioning and in the immune system免疫系统.,A: (1) Nutrition (营养) (2) Maintenance of colloid osmotic pressure(胶体渗透压): albumin(清蛋白) (3) Carrier protein (载体蛋白) (4) pH buffer system (pH缓冲系统)(5) Defence system (防御系统) : Immunoglobulins(免疫球蛋白) Complement system(补体系统)(6) Coagulation(凝血)and fib
5、rinolysis(纤维蛋白溶解)(7) Inhibit the protease(抑制蛋白酶)(8) Promotion(催化作用),1.1.2 Classify (1) Salting out(盐析)Q: What fractions can be separated from the serum proteins by salting out(盐析)?A: 2 fractions: albumin (Alb), globulin(Glo),(2) Electrophoresis (电泳)Q: What zones can be separated from the serum prote
6、ins by cellulose acetate membrane electrophoresis (CAME,乙酸纤维素薄膜电泳)? A: 5 zones: Alb, 1, 2 , , -globulinQ: What fractions can be separated from the serum proteins by polyacrylamide gel electrophoresis (PAGE,聚丙烯酰胺凝胶电泳) A: more than 30 zonesQ: Which electrophoresis can determine the molecular weight of
7、 proteins ?A: SDS-PAGE,(3) 功能分类法Q: 下列血浆蛋白质各有什么功能？A: P31:表3-1 载体蛋白类：Prealbumin前清蛋白, Haptoglobin触珠蛋白, Ceruloplasmin铜蓝蛋白, Transferrin转铁蛋白, lipoprotein脂蛋白免疫球蛋白类：IgG, IgA, IgM补体蛋白类：C3, C4 凝血蛋白类：Coagulation factor凝固因子蛋白酶抑制物：1 antitrypsin抗胰蛋白酶, 2 macroglobulin巨球蛋白 血清酶类： Acetylcholine esterase胆碱酯酶其他：1 acid
8、glycoprotein酸性糖蛋白, 1 fetoprotein甲胎蛋白, 2 microglobulin微球蛋白, C-reactive protein (CRP)反应蛋白,1.2 Electrophoresis of serum protein血清蛋白质的电泳,蛋白质测定方法 后面单独讲1.2.1 血清蛋白CAME正常组分Q: Are all the plasma proteins synthesized in liver ?A: No, except -globulins. Q: What are the normal components of serum proteins by CA
9、ME ?A: 5 zones: Alb, 1, 2 , , -globulin,60% of plasma proteins are made up of the albumin, which are major contributors to osmotic pressure of plasma and assists in the transport of lipids and steroid hormones类固醇激素. Globulins make up 35% of plasma proteins and are used in the transport of ions, horm
10、ones, lipids and assisting in immune function.4% is fibrinogen纤维蛋白原 and this is essential in the clotting凝固 of blood. Regulatory proteins which make up less than 1% of plasma proteins are proteins such as enzymes, proenzymes酶原 and hormones.,各 albumin : 57%-68%, 3552g/L组 1 -globulin : 1.0%-5.7%, 1.04
11、.0g/L分 2 -globulin : 4.9%-11.2%, 4.08.0g/L含 -globulin : 7%-13%, 5.010.0g/L量 -globulin : 9.8%-18.2%, 6.013.0g/L,Alb 1 2 ,+-,扫描 ,Q: 血清蛋白质CAME的图谱特点？,血清蛋白质CAME的补充说明,Q: If the sample is plasma，what result will appear?A: Fibrinogen zone will appear between and .Q: 5 zones = 5 proteins? A: NoQ: What are th
12、e direction of electrophoresis?A: pI pH, Pr- ,positive electrode pI pH, Pr+,negative electrodeQ: Why 1 zone is light color?A: Lipid and glucoprotein (糖蛋白) can not be stained(染色).,1.2.2 各电泳区带的主要蛋白质P34:表3-3,Q: Which zones are the following proteins located in?A:1 区带 :1-抗胰蛋白酶, 1-酸性糖蛋白, 甲胎蛋白, HDL 2区带 :
13、触珠蛋白, 2-巨球蛋白, 铜蓝蛋白 区带 : 1区带: 运铁蛋白, LDL, C4 , 2区带:C3 , 2-球蛋白, 纤维蛋白原 区带 : 免疫球蛋白A,G,M，C-反应蛋白,1.2.3 异常电泳图谱 P33 图3-2,Q:常见的异常电泳图谱有哪些？各有什么特征？1.M蛋白血症型：主要见于多发性骨髓瘤、浆细胞病。特点是出现在、区带出现M蛋白带*。 2.蛋白缺乏型：临床上较少见，主要包括肺部疾病引起的1抗胰蛋白酶缺乏症、球蛋白缺乏症等。表现为、显著降低。 3.肾病型：见于急慢性肾炎、肾病综合征，肾功能衰竭等。表现为Alb降低，2和升高，分不开。 4.炎症型：见于各种急慢性炎症和急性应激反应。
14、 1、2和三种球蛋白均增高。 5.肝硬化肝病型：见于慢性活动性肝炎、肝硬变等。表现为：Alb降低、和增高。可出现“-桥”，肝脏纤维增生导致IgA增高所致。,1.4 The acute-phase reaction and the acute-phase reaction proteins急性时相反应与急性时相反应蛋白1.4.1 Q: What is APRP?Following inflammation (炎症) , trauma (创伤),infection, etc. the body responds by: An increase of many plasma proteins (e.
15、g. C-反应蛋白, 结合珠蛋白等) A decrease of many plasma proteins (e.g. 清蛋白, 前清蛋白 , 转铁蛋白等)The responds are acute-phase reaction.The proteins above are the acute-phase reaction proteins (APRP).,急性时相反应*：在急性炎症性疾病如手术、创伤、感染、心肌梗死、肿瘤等，某些血浆蛋白如 AAT、 AAG 、CRP等浓度显著升高或升高，而另一些血浆蛋白如PA、Alb、TRF等则出现相应的低下。急性时相反应蛋白*：上述这些血浆蛋白质统称为A
16、PRP 。负性急性时相反应蛋白*：PA 、Alb、TRF等在急性时相反应中出现相应的低下的蛋白质。,注意：是对炎症的一般反应而非对某一疾病的特异性反应。1.4.2 Possible mechanism(可能机制)： Inflammation body release some active compounds (e.g. cell factor) synthesis of APRPor. 炎症机体释放某些活性物质(如细胞因子) APRP的合成or,1.3 血浆蛋白质主要组分的生化检验,1.3.1 前清蛋白( Prealbumin, PA) Q: Characteristics ? A: Syn
17、thesised in liver cell. Electrophoresis zone is in front of albumin. MW 55000. Half-life 1.9d. Reference value 0.2-0.4g/L.,Q: Function?A: Transport vitamin A, T3, T4 视黄醇-视黄醇结合蛋白-前清蛋白复合物Q: Clinical significance ? A: Malnutrition(营养不良); Liver disease, more sensitive than Alb and TRF; Acute-phase respo
18、nse, Negative acute phase protein负性急性时相反应蛋白,http:/www.labtestsonline.org/How is it used?The prealbumin test is used to help your doctor diagnose problems with your nutrition. Prealbumin most often is used to help doctors diagnose protein-calorie malnutrition蛋白质-热量缺乏性营养不良. In this condition, which ca
19、n affect more than 30% of hospitalized patients. This type of malnutrition can lead to complications并发症 and even death if not treated. Children with malnutrition may fail to thrive茁壮成长 or have stunted growth发育障碍,生长矮小.,The test is also used to make an assessment of nutritional status: before a schedu
20、led预定的 surgery, in patients who are hospitalized with certain conditions, and in patients who are chronically ill慢性病.,Many patients have a decline降低 in nutrition during their hospital stay, especially after surgery. Studies have shown that good nutrition prior to先前的 surgery helps to avoid complicati
21、ons并发症, such as pneumonia肺炎 and infection感染, after surgery. If the prealbumin test indicates that you are malnourished or have poor nutrition, your doctor can help correct your diet so you get stronger before your surgery. Albumin may be tested instead to determine nutritional status.,When is it ord
22、ered?A doctor orders a prealbumin test when signs of malnutrition or poor nutrition are present. Signs of malnutrition include extreme weight loss, stunted growth (in a child), weakened resistance to infection. Hair may become brittle易碎的 or begin to fall out, the skin may be dry or yellowish, muscle
23、s may feel weak. In younger women, menstrual periods月经期 may stop.,What does the test result mean?The prealbumin measurement reflects the state of your nutrition. If prealbumin is low, other proteins and substances in your blood also may be low. If your test shows that prealbumin is low, your nutriti
24、on probably needs to be corrected. If prealbumin is very low, you may be considered malnourished and need immediate medical attention.,Lower levels of prealbumin may be seen in patients with: severe or chronic illness, such as cancer; hyperthyroidism甲状腺功能亢进; liver disease; serious infections; and ce
25、rtain digestive disorders消化紊乱.,1.3.2 清蛋白(Albumin,Alb)(1) 性质Q: Characteristics ? A: Synthesised in liver cell. MW 66200. The only plasma protein does not contain sugar. Half-life 19d. Reference value 35-52g/L.,Q: Why selective exclusion排除 of albumin from the glomerular filtrate肾小球滤液 ?A: Albumin (pH 7
26、.4, in the body) is negatively charged. The glomerular basement membrane肾小球基底膜 is also negatively charged in the body. Q: 为什么正常尿中蛋白极低？A: 滤过少，0.04%；重吸收多97%； 正常尿液中蛋白含量甚少，定量检查结果24小时尿蛋白定量在2080mg（其中白蛋白占40、球蛋白占15、泌尿道组织蛋白占40）。如果24小时尿蛋白定量超过150mg，则称为蛋白尿。,(2) 生理功能Q: Function? A: Carrier protein 载体蛋白 运输胆红素、脂肪酸
27、、胆汁酸盐、激素、金属离子、药物等。 Maintenance of colloid osmotic pressure 维持胶体渗透压 过低引起腹水、水肿等，需输入Alb。 pH buffer system pH 缓冲系统 Nutrition 营养作用 组织营养(3) 检测后面讲,(4) Q: Clinical significance 临床意义*： A: Hypoalbuminemia（低清蛋白血症）,主要特征：血清总蛋白,以清蛋白减低为主检查结果： Alb:44.2%();1:4.6%(N);2:14.6%(); :18.5%(); :18.1%(N);常见于：慢性营养失调、肝硬化、肝炎、肾
28、炎、肾病综合症,产生原因：1) Reduced synthesis (合成减少): liver disease, 尤其是慢性的 malnutrition,http:/www.labtestsonline.org/ What is the difference between prealbumin, and albumin tests? The prealbumin test measures a protein that reflects your nutritional status, particularly before and after surgery, or if you are
29、hospitalized or taking nutritional supplements. Albumin testing is more often used to test for liver or kidney disease or to learn if your body is not absorbing enough amino acids. Albumin can also be used to monitor nutritional status. However, prealbumin changes more quickly, making it more useful
30、 for detecting changes in short-term nutritional status than albumin.,2) Abnormal loss (异常丢失) : The liver can normally replace albumin losses of up to 5g/day. Greater losses may occur in nephrotic syndrome(肾病综合症) , gastrointestinal tract disease (胃肠道疾病) and in burns or certain skin diseases 肝脏能代偿每天5
31、克的清蛋白丢失。过多的清蛋白丢失可能发生于肾病综合症、胃肠道疾病、烧伤及某些皮肤病。,3) Increased catabolism(分解代谢增加)： As a result of injury(e.g. major surgery大外科or trauma), infection 由损伤(外科手术或创伤)，感染等引起。 一种负性急性时相反应蛋白 Negative acute phase protein4) Altered distribution（分布失衡）： Due to increased capillary permeability (毛细血管渗透性), which enables al
32、bumin to leak into the extravascular(血管外的) compartment(室,间隔)(e.g. ascites腹水) 由于毛细血管渗透性增加，导致清蛋白渗透入血管外(如腹水)。,5) Analbuminemia(无清蛋白血症): It is a rare disorder in which plasma albumin is usually less than 1.0 g/L 一种血浆清蛋白低于1.0g/L的罕见变异 However,there may be no symptoms not even edema(水肿)due to compensatory
33、increases in plasma globulins 然而可能不表现病症，甚至没有水肿，这是由于血浆球蛋白的代偿性增加。,无清蛋白血症,主要特征：血浆清蛋白的显著降低，严重时有时可降为零。产生原因：可能由于清蛋白合成功能遗传性缺陷或明显低下所致。该病患者的清蛋白含量尽管极低，而其血浆胶体渗透压仍为正常人的 1/2左右，这是由于球蛋白代偿性增加所致, Hyperalbuminemia (高清蛋白血症 ): Increased plasmaalbumin is found in dehydration(脱水). Estimate the ligand(配体) which bind with
34、the albumin (评价与清蛋白结合的配体) Individual nutritional state(个体营养状态) 35 g/L normal (正常) 28-34 g/L mild deficiency(轻度缺乏) 21-27 g/L moderate deficiency(中度缺乏) 21 g/L severe deficiency(严重缺乏), Hereditary abnormalities(遗传性变异) Bisalbuminemia(双清蛋白血症) Many albumin variants(变异) occur in the healthy population，and h
35、ave no pathological(病理的) significance 多种清蛋白变异会发生在健康人群，不表现病理症状。,主要特征：在清蛋白部位有两个区带，光密度计扫描出现双峰，呈剪刀状。产生原因：分为持久型和暂时型两种。持久型：一种家族性清蛋白异常的遗传疾病；暂时型：肾功能不全患者在治疗期间使用大剂量的-内酰胺类抗生素，可形成快泳动性的清蛋白成分，治疗中断即逐渐消失。,双清蛋白血症,http:/www.labtestsonline.org/Why get tested?To screen for a liver disorder or kidney disease or to evalu
36、ate nutritional status, especially in hospitalized patients (prealbumin is sometimes used instead of albumin in this situation).When to get tested?If your doctor thinks you have symptoms of a liver disorder or kidney disease, if you havea recent, rapid weight change, or prior to a planned surgery.Sa
37、mple required?A blood sample drawn from a vein in your arm.,How is it used?Since albumin is low in many different diseases and disorders, albumin testing is used in a variety of settings to help diagnose disease, to monitor changes in health status with treatment or with disease progression, and as
38、a screen that may serve as an indicator指示 for other kinds of testing.,When is it ordered?A physician orders a blood albumin test (usually along with several other tests) if a person seems to have symptoms of a liver disorder or nephrotic syndrome肾病综合征. Doctors may also order blood albumin tests when
39、 they want to check a persons nutritional status, for example, when someone has lost a lot of weight.,What does the test result mean?Low albumin levels can suggest liver disease. Other liver enzyme tests are ordered to determine exactly which type of liver disease. Low albumin levels can reflect dis
40、eases in which the kidneys cannot prevent albumin from leaking from the blood into the urine and being lost. In this case, the amount of albumin (or protein) in the urine also may be measured. Low albumin levels can also be seen in inflammation, shock, and malnutrition. Low albumin levels may also s
41、uggest conditions in which your body does not properly absorb and digest protein or in which large volumes of protein are lost from the intestines肠. High albumin levels usually reflect dehydration脱水.,Is there anything else I should know?Certain drugs increase albumin in your blood, including androge
42、ns雄激素, growth hormones, and insulin胰岛素. If you are receiving large amounts of intravenous fluids静脉内液, the results of this test may be inaccurate.Is anyone at high risk for abnormal albumin levels?Individuals who have chronic liver disease and kidney disorders are at highest risk for developing abnor
43、mal albumin levels. In addition, individuals whose GI胃肠的 tract doesnt absorb nutrients properly and individuals who have prolonged diarrhea腹泻 can develop abnormal albumin levels.,英文例题Which of the following is not a major function of plasma proteins in the blood?1. membrane permeability 2. clotting 3
44、. osmotic balance 4. pH buffering 5. defense,1.3.3 1抗胰蛋白酶(1-antitrypsin, AAT)(1) 性质Q: Characteristics ?A: AAT是1区带的主要组分, 占90%Q:1区带染色浅？A: 1区带主要组分的AAT含糖高Q: Function? A: AAT is a main protease inhibitor (90% of the inhibitory action)。一种主要的蛋白酶抑制物, 占蛋白酶抑制作用的90%。,Q: AAT活性与pH的关系及意义？A: 与pH的关系：中性和弱碱性时，AAT活性高，
45、抑制作用大；酸性时AAT活性低，pH4.5基本无活性。 意义：？,2. 临床意义Q: Clinical significance？ Emphysema(肺气肿) About 1of patients with emphysema have AAT deficiency, but this percentage is much higher in young patients(20-30 age group). 大约1的肺气肿患者伴有AAT缺陷，这一比例在20-30岁的年轻病人中更高。 One of the APRPs,http:/www.labtestsonline.org/Why get t
46、ested?To help diagnose the cause of early onset早发emphysema and/or liver dysfunction异常. To establish the risk of developing alpha-1 antitrypsin-related emphysema and/or liver disease and the likelihood可能性 that children might inherit the risk.When to get tested?When you show signs of liver disease as
47、an infant or young child, when you develop emphysema (a disease that damages the lungs) before age 40, or when you have a close relative亲戚 with alpha-1 antitrypsin deficiency.,1.3.4 1-酸性糖蛋白(1-acid glycoprotein AAG)1. 性质Q: Characteristics ?A: 血浆中含糖量最高、酸性最强的糖蛋白 pI 2.74.0 典型的急性时相反应蛋白2. 临床意义Q: Clinical
48、significance？ AAG: 急性时相反应指标，反映炎症。 AAG: 营养不良、严重肝损害、肾病综合征、胃肠道蛋白流失等情况下降低。,1.3.5 触珠蛋白( Haptoglobin , Hap)1. 功能Q: Function? A: Bind hemoglobin(血红蛋白,Hb) to form Hap-Hb complexes which are then rapidly broken down in the lymphoreticular system(淋巴网状内皮系统)Recycling of amino acid and iron Iron can be conserved. 与血红蛋白结合形成Hap-Hb复合物(1:2)后转运至淋巴网状内皮系统分解氨基酸和铁被再利用 机体能保留铁，,
