ChapterDigestionandAbsorption消化與吸收PPT課件

1、Chapter 5 Digestion and Absorption (消化與吸收消化與吸收)第1頁/共72頁Digestion (消化): The break-down process whereby the structurally complex foodstuffs of the diet are converted into smaller absorbable units by the enzymes produced within the digestive system ( (食物在消化道內(nèi)被分解為小分子物質(zhì)的過程) ) Mechanical digestion (機(jī)械性消化)

2、 ) Chemical digestion (化學(xué)性消化) )第2頁/共72頁 Absorption (吸收): The process that the smaller absorbable units of digestion get across the alimentary tract mucosa and come into blood or lymph. ( (食物經(jīng)消化后通過消化道粘膜進(jìn)入血液或淋巴的過程) )第3頁/共72頁Section1 Structure of Digestive Tract(消化管的結(jié)構(gòu)消化管的結(jié)構(gòu))Intracellular digestion (胞內(nèi)

3、消化胞內(nèi)消化) Extracellular digestion (胞外消化胞外消化) 第4頁/共72頁1.Human Digestive Tract (人的消化管) 粘膜層： 上皮 上皮下層 粘膜肌層 粘膜下層 組織結(jié)構(gòu) (Submucous layer) 環(huán)行肌 胃部是三層 Smooth muscle 內(nèi)斜,中環(huán),外縱 縱行肌 漿膜 : C.T (Serous membrane) (Tissue structure) (Mucous layer)第5頁/共72頁2.The Innervation of Digestive Tract (消化管的神經(jīng)支配消化管的神經(jīng)支配) Extrinsic

4、NS & Intrinsic NS 第6頁/共72頁Sympathetic nerve (交感N ): The subdivision of the autonomic nervous system that dominates in “fight-or-flight” emergency or stressful situations and perpares the body for strenuous physical activity. (源自 T5 T10 & L1 L2在腹神經(jīng)節(jié)和腸系膜上下N節(jié)換元) 第7頁/共72頁運(yùn)動(dòng)及分泌內(nèi)在N元第8頁/共72頁 副：延髓背核

5、 疑核 運(yùn)動(dòng)及分泌第9頁/共72頁Myenteric plexus (肌間肌間N叢叢) Submucous plexus (粘膜下粘膜下N叢叢) Intrinsic plexus (內(nèi)在N叢)： 包括感覺、中間、運(yùn)動(dòng)神經(jīng)元構(gòu)成一個(gè)完整 且相對(duì)獨(dú)立的整合系統(tǒng) 第10頁/共72頁Section 2 The Movement and Regulation of Digestive Tract(消化管的運(yùn)動(dòng)及調(diào)節(jié)消化管的運(yùn)動(dòng)及調(diào)節(jié)) The movement of digestive tract (消化道的運(yùn)動(dòng)消化道的運(yùn)動(dòng)): Mastication (咀嚼咀嚼) Deglutition (吞咽吞咽)

6、 Gastrointestinal movement (胃腸運(yùn)動(dòng)胃腸運(yùn)動(dòng))第11頁/共72頁Reflex (反射): Any response that occurs automatically without conscious effort. (在NS的參與下對(duì)刺激的規(guī)律性應(yīng)答) Reflex arc (反射弧): The components of a reflex arc include a receptor, afferent pathway, integrating center, efferent pathway, and effector. (感受器 傳入N N中樞 傳出N 效

7、應(yīng)器 )第12頁/共72頁1. Gastric movement (胃的運(yùn)動(dòng)) (1)Receptive relaxation(胃的容受性舒張) Definition: food stimulate the receptors in pharynx and esophagus, through vagus nerve arouse relaxation of fundus and body of stomach muscle. (食物刺激咽、食管等處感受器經(jīng)迷走神經(jīng)反射性引起胃底、胃體肌舒張) significance第13頁/共72頁(2)Tonic contraction (緊張性收縮緊張

8、性收縮)(3)Peristalsis (蠕動(dòng)蠕動(dòng))Gastric BER (胃的基本電節(jié)律胃的基本電節(jié)律):It stems from longitudinal muscle of greater curvature, 35 times per minutes, amplitude is about 515 mv.(起源于胃大彎的縱行肌層，每分鐘35次，振幅約515 mv )第14頁/共72頁 Function of peristalsis (蠕動(dòng)) ： Lead to ample mixing of chyme and digestive juice, this is facilitated

9、 for chemical digestion. 使食糜與消化液充分混合，利于化學(xué)性消化 Mill food (mechanical digestion) 磨碎食物 (即機(jī)械性消化) Push chyme 推進(jìn)食糜 第15頁/共72頁2.Gastric Emptying and Its Regulation (胃的排空及其控制胃的排空及其控制)Definition: The process that food enter into duodenum from stomach.(食物由胃排入12指腸的過程) (1)(1)胃排空胃排空 (gastric emptying) 第16頁/共72頁Emp

10、tying velocity (排空速度)：Sugarproteinfat;Sparse, thin, isosmotic quick (稀、細(xì)、等滲 快) (反之則慢)第17頁/共72頁(2) Regulation of gastric emptying (胃排空的調(diào)控胃排空的調(diào)控) Entogastric factors accelerate emptying (胃內(nèi)因素促進(jìn)排空胃內(nèi)因素促進(jìn)排空)： Entogastric food（Nr） (胃內(nèi)食物) Gastrin （Hr） (胃泌素) 第18頁/共72頁Factors of duodenum inhibit emptying (12

11、脂腸因素抑制排空)： Gastrointestinal reflex（Nr）(腸胃反射) Enterogastrone （Hr） (腸抑胃素)第19頁/共72頁Emptying process(排空過程排空過程) )： Entogastric food(胃內(nèi)食物胃內(nèi)食物) ) emptying stopped (排空停排空停止止)motility of the stomach (胃運(yùn)動(dòng)胃運(yùn)動(dòng)) 胃運(yùn)動(dòng)胃運(yùn)動(dòng) 幽門括約肌舒張幽門括約肌舒張 幽門括約肌收縮幽門括約肌收縮 胃內(nèi)壓胃內(nèi)壓1212指腸內(nèi)壓指腸內(nèi)壓N (腸胃反射)H (腸抑胃素)腸內(nèi)胃酸被中和食物被消化吸收 第20頁/共72頁3. The

12、 movements of small intestine (小腸的運(yùn)動(dòng)小腸的運(yùn)動(dòng))(1)Tonic contraction (緊張性收縮緊張性收縮) Functions： Maintain basic pressure (維持基礎(chǔ)壓力維持基礎(chǔ)壓力) The basis of movements (是腸運(yùn)動(dòng)的基礎(chǔ)是腸運(yùn)動(dòng)的基礎(chǔ)) Fix and keep shape of small intestine (維持小腸的位置形狀維持小腸的位置形狀)第21頁/共72頁 (2)Segmentation contraction (分節(jié)運(yùn)動(dòng)分節(jié)運(yùn)動(dòng)) 第22頁/共72頁Functions： It can

13、lead to ample mixing of chyme and digestive juice, this is facilitated for chemical digestion. (使食糜與消化液充分混合，利于化學(xué)性消化) It can accelerate close contact of chyme and intestinal wall ,this is facilitated for absorption. (使食糜與腸壁緊密接觸，利于吸收)第23頁/共72頁 It can press intestinal wall, accelerate blood and lymph c

14、ircumfluence. (擠壓腸壁而促進(jìn)血液、淋巴回流) (3)Peristalsis (蠕動(dòng)) Peristalsis function : push chyme (推進(jìn)食糜)第24頁/共72頁(4)Large intestinal movement and defecation (大腸運(yùn)動(dòng)和排便大腸運(yùn)動(dòng)和排便)The movement forms of large intestine (大腸運(yùn)動(dòng)形式大腸運(yùn)動(dòng)形式) 1)袋狀往返運(yùn)動(dòng)袋狀往返運(yùn)動(dòng) 2)分節(jié)或多袋推進(jìn)運(yùn)動(dòng)分節(jié)或多袋推進(jìn)運(yùn)動(dòng) 3) Peristalsis (蠕動(dòng)蠕動(dòng))(mass peristalsis,集團(tuán)蠕動(dòng)集團(tuán)蠕動(dòng)) 第2

15、5頁/共72頁 Brain stem , cerebral cortex (腦干、大腦皮層腦干、大腦皮層) S2-S4直腸牽張直腸牽張R 內(nèi)括約肌松馳Defecation reflex (排便反射)外括約肌松馳第26頁/共72頁(5)Regulation of digestive tract (消化管運(yùn)動(dòng)的調(diào)節(jié)消化管運(yùn)動(dòng)的調(diào)節(jié))Electrical activity (電活動(dòng)電活動(dòng)) BER APNerve factors (神經(jīng)因素神經(jīng)因素) Sympathetic nerve (-) gastrointestinal movement 交感N (-) 胃腸運(yùn)動(dòng) Vagus nerve (+

16、) gastrointestinal movement 迷走N (+) 胃腸運(yùn)動(dòng)第27頁/共72頁Intraparietal nerve plexus (壁內(nèi)N叢) : Regulating gastrointestinal movement (調(diào)節(jié)胃腸運(yùn)動(dòng))Cerebral cortex(大腦皮層) : Interest for food effects digestion. Psychogenic enterorrhea (對(duì)食物的好惡對(duì)消化的影響 精神性腹瀉)第28頁/共72頁 3. Humoral factors (體液因素體液因素) ): Gastrointestinal hormo

17、ne (主胃腸激素主胃腸激素):): 抑胃肽NEmovementmovement第29頁/共72頁Section 3 The Secretion and Regulation of Digestive Juice (消化液的分泌及調(diào)節(jié)消化液的分泌及調(diào)節(jié))1.The secretion of saliva (唾液的分泌唾液的分泌)第30頁/共72頁(1)The characters 、components and functions of saliva (唾液性質(zhì)與成分與作用) ) Moisten , dissolve food (濕潤(rùn)、溶解食物) clean, protect mouth ca

18、vity (清潔、保護(hù)口腔) lubricate , hydrolyze amylum , kill bacteria (潤(rùn)滑 水解淀粉 殺菌)第31頁/共72頁(2) The regulation of salivary secretion (唾液分泌的調(diào)節(jié)唾液分泌的調(diào)節(jié)) Double excitation effect of sympathesis nerve and parasympathesis nerve (交感與副交感雙重興奮作用) Conditioned reflex (條件反射) Unconditioned reflex (非條件反射)第32頁/共72頁2. Gastric

19、secretion (胃液的分泌胃液的分泌) (1)Characters ,components and functions of gastric juice (胃液胃液的性質(zhì)、成分和作用的性質(zhì)、成分和作用) ) 無色透明，無色透明，第33頁/共72頁 Pepsinogen (胃蛋白酶原胃蛋白酶原) chief cell secretion (主細(xì)胞分泌主細(xì)胞分泌) ) +第34頁/共72頁 Mucus and HCO3HCO3- - (粘液與碳酸氫鹽粘液與碳酸氫鹽)胃粘液-碳酸氫鹽屏障第35頁/共72頁 Functions： Lubricate, protect gastric mucosa

20、, gastric mucosal barrier; recovering gastric mucosal epithelia. (潤(rùn)滑、保護(hù)胃粘膜胃粘液屏障，胃粘膜屏障; ;胃粘膜上皮的更新)第36頁/共72頁The secretion of hydrochloric acid - parietal cell ( 鹽酸壁細(xì)胞分泌鹽酸壁細(xì)胞分泌) The functions of hydrochloric acid (鹽鹽 酸酸 作作 用用):): 第37頁/共72頁 1)Activate pepsinogen and supply suitable PH to pepsin (激活胃蛋白酶原

21、并給胃蛋白酶提供 活動(dòng)所需的酸性pH) 2) Kill bacteria (殺菌) 3)Accelerate denaturation of protein, and facilitated to digestion (使蛋白質(zhì)變性易于消化)第38頁/共72頁4)Accelerate the secretion of pancreatic juice、 bile、small intestinal juice. (促進(jìn)胰液、膽汁、小腸液分泌)5)Accelerate the absorption of small intestinal to iron and calcium. (促進(jìn)小腸對(duì)鐵、鈣

22、的吸收)第39頁/共72頁Function：1)Protect B12 doesnt hydrolyzed by digestive enzyme (保護(hù)B12不被消化酶水解)2)Accelerate the absorption of ileum mucosa to B12. (促進(jìn)B12經(jīng)回腸粘膜吸收)Intrinsic factor (內(nèi)因子內(nèi)因子) 第40頁/共72頁(2)The regulation of gastric juice secretion (胃液分泌的調(diào)節(jié)胃液分泌的調(diào)節(jié)) Sham feeding (假飼) Fig 5-18第41頁/共72頁Gastric juice

23、secretion of cephalic phase(頭期胃液分泌) The food stimulates cephalic receptor cause gastric juice secretion. (食物刺激頭部感受器引起的胃液分泌)第42頁/共72頁 Cephalic R nerve center gastric gland secrete gastric juice G cell - gastrin（胃泌素） characters : quantity and acidity is high, digestive enzyme is higher. (量、酸度很高，消化力(酶)

24、尤高 ) (頭部R)(中 樞)(胃腺分泌胃液)第43頁/共72頁Gastric juice secretion of gastric phase (胃期胃液分泌) Food stimulates stomach cause the gastric juice secretion.(食物刺激胃引起的胃液分泌） 第44頁/共72頁 胃底胃體機(jī)械刺激胃底胃體機(jī)械刺激 中樞中樞胃腺胃腺 分泌胃液分泌胃液食物食物 胃幽門部機(jī)械刺激胃幽門部機(jī)械刺激 壁內(nèi)神經(jīng)叢壁內(nèi)神經(jīng)叢 胃幽門部化學(xué)刺激胃幽門部化學(xué)刺激幽門部幽門部G G細(xì)胞細(xì)胞 胃泌素胃泌素 Characters: Acidity is quite hi

25、gh, digestive enzyme is weaker than cephalic phase. (酸度高，消化力酸度高，消化力(酶酶)比頭期的弱比頭期的弱)第45頁/共72頁Gastric juice secretion of intestinal phase (腸期胃液分泌) The food stimulates intestine cause the gastric secretion （食物刺激腸引起的胃液分泌）第46頁/共72頁 S m a l l intestine (小腸小腸) Gastrin，entero-oxyntin（胃泌素、腸泌酸素 )Gastric gland

26、secrete gastric juice(胃腺分泌胃液)characters: few quantity. (量少)第47頁/共72頁Inhibitory regulation of gastric secretion (胃液分泌的抑制性調(diào)節(jié)胃液分泌的抑制性調(diào)節(jié)) ) 1)HCl 胃竇粘膜胃竇粘膜G G細(xì)胞細(xì)胞 mucosal D cell somatostain intestinal mucosa S cell secretin duodenal ampulla bulbomycin (粘膜D細(xì)胞)(生長(zhǎng)抑素)(腸粘膜S細(xì)胞)(促胰液素)(12指腸球部)(球抑胃素)第48頁/共72頁2)2

27、) Fat small intestine enterogasterone mucosa (腸抑胃素腸抑胃素) ( (小腸粘膜小腸粘膜) ) gastric juice (胃液胃液) ) gastric movement (胃運(yùn)動(dòng)胃運(yùn)動(dòng)) ) 第49頁/共72頁3)Hypertonic solution small intestine mucosa (高張溶液高張溶液) () (小腸粘膜小腸粘膜) ) osmotic pressure R R inhibitive H H ( (小腸滲透壓小腸滲透壓R) (R) (抑制性抑制性H)H)第50頁/共72頁 4)PGE 4)PGE Vagus ne

28、rve, gastrin ( (迷走迷走N N、胃泌素、胃泌素) ) gastric wall release PGE (胃壁釋放胃壁釋放PGE) 第51頁/共72頁5)The effects of different food on gastric juice secretion (不同食物對(duì)胃液分泌的作用不同食物對(duì)胃液分泌的作用) Protein sugarfat (蛋白質(zhì)糖類脂肪)Corn, sweet potato, alcohol, coffee (玉米面,白薯,紅薯,酒精,咖啡)第52頁/共72頁3.The secretion of pancreatic juice (胰液的分泌胰

29、液的分泌) HCO3-H2OEnzymesSmall vessel cell(小導(dǎo)管細(xì)胞)Acinar cell(腺泡細(xì)胞)Pancreas (胰腺)第53頁/共72頁(1)The characters、components and functions of pancreatic juice (胰液的性質(zhì)成分和作用胰液的性質(zhì)成分和作用) CharactersAchromia and tasteless ( (無色無臭無色無臭) )第54頁/共72頁Components and functions Water dilute food (稀釋食物稀釋食物) )第55頁/共72頁 Sodium bi

30、carbonate (碳酸氫鹽碳酸氫鹽) ) counteract acid and supply suitable pH for activity of digestive enzyme in small intestine (中和胃酸并提供小腸內(nèi)消化酶活動(dòng)所需的最適pH)HCO3-第56頁/共72頁Organic components : digestive enzymes (有機(jī)成分主要是各種消化酶有機(jī)成分主要是各種消化酶) )： Pancreatic amylase (胰淀粉酶胰淀粉酶) malt sugar, glucose (麥芽糖、葡萄糖麥芽糖、葡萄糖)第57頁/共72頁 Lip

31、ase (胰脂肪酶胰脂肪酶 ) Fatty acid, glyceride, glycerin ( (脂肪酸、甘油一酯、甘油脂肪酸、甘油一酯、甘油) )第58頁/共72頁 胰蛋白酶胰蛋白酶 (trypsin) 糜蛋白酶糜蛋白酶 (chymotrypsin) ( (多肽、多肽、AA)AA) Trypsinogen(胰蛋白酶原)Chymotrypsinogen (糜蛋白酶原)第59頁/共72頁 Others Carboxypeptidase 羧基肽酶羧基肽酶 Deoxyribonuclease (脫氧脫氧)核糖核酸酶核糖核酸酶 第60頁/共72頁(2)The regulation of pancr

32、eatic juice (胰液分泌的胰液分泌的調(diào)節(jié)調(diào)節(jié)) ) Nr Enzyme is quite abundant, H2O and HCO3-are few. (酶很豐富，但酶很豐富，但H2O、HCO3-很少很少)HrHr Secretin (促胰液素促胰液素) Enzyme is quite few, H2O and HCO3- are abundant. (H2O (H2O、HCO3HCO3- -很豐富，但酶很少很豐富，但酶很少 ) )第61頁/共72頁 Cholecystokinin (膽囊收縮素 ) Enzyme is abundant, quantity is slightly

33、increased. (酶多，量增加少許) Gastrin (胃泌素) Enzyme is abundant, quantity is slightly increased. (酶多，量增加少許)第62頁/共72頁 Secretin (促胰液素促胰液素) )Food ( (刺激強(qiáng)度：鹽酸刺激強(qiáng)度：鹽酸 蛋白分解產(chǎn)物蛋白分解產(chǎn)物 脂酸鈉脂酸鈉) ) small intestine secretin( (促胰液素促胰液素) ) mucosa S cell ( (小腸粘膜小腸粘膜S S細(xì)胞細(xì)胞) ) 胰腺小導(dǎo)管細(xì)胞 第63頁/共72頁 Cholecystokinin, CCK (膽囊收縮素膽囊收縮素)Food ( (蛋白分解產(chǎn)物蛋白分解產(chǎn)物 脂酸鈉脂酸鈉 鹽酸鹽酸 脂肪脂肪) )small intestine CCK CCK mucosa I cell( (小腸粘膜小腸粘膜I I細(xì)胞細(xì)胞) ) cholecyst contraction pancreatic acinar cell (膽囊收縮) (胰腺腺泡細(xì)胞)第64頁/共72頁4.The Secretion and Regulation of Other Digestive Juice(其它消化液的分泌及調(diào)節(jié))Bile (膽汁): Vagus N (迷走N) G., S., CCK (+)