水、电解质乱 三、静水压和渗透压 (Hydrostatic& Osmotic pressure H2O 压力高■ 压力低 1.静水压( Hydrostatic pressure) H2 O H2oH2O H2O H2o 相邻的两个体液腔隙,由于压力不 H2O H2O HO H2o H2O 同,水必然从压力高的腔隙向压力低的 H2o H2O HO 腔隙转移,这种促使水转移的压力叫做 静水压 静水压 O 2.渗透压( Osmotic pressure) 渗透压高← 渗透压低 如果相邻两个体液腔隙的静水压相 H2O 等,而体液中溶质的浓度不同,那么水 ⊙⊙o⊙氵 H2o 将由溶质浓度低(渗透压低)的腔隙向oo6°a ⊙⊙ 溶质浓度高(渗透压高)的腔隙转移, H2O 这种现象称为渗透。推动渗透的力称为 渗透压 渗透压
三、静水压和渗透压 (Hydrostatic& Osmotic pressure) 1.静水压(Hydrostatic pressure) 相邻的两个体液腔隙,由于压力不 同,水必然从压力高的腔隙向压力低的 腔隙转移,这种促使水转移的压力叫做 静水压。 H2O H2O H2O H2O H2O H2O H2O H2O H2O H2O H2O H2O H2O H2O 静水压 压力高 压力低 H2O 渗透压高 渗透压低 ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ ⊙ H2O H2O ⊙ H2O H2O H2O H2O H2O H2O 渗透压 H2O 2.渗透压(Osmotic pressure) 如果相邻两个体液腔隙的静水压相 等,而体液中溶质的浓度不同,那么水 将由溶质浓度低(渗透压低)的腔隙向 溶质浓度高(渗透压高)的腔隙转移, 这种现象称为渗透。推动渗透的力称为 渗透压。 水、电解质紊乱
水、电解质乱 四、钠的平衡调节( Balance of sodium) (一)人体钠的含量与分布( Content& distribution of body sodium) IContent of sodium 58mmol/kg, Total body sodium: 60-80g/60kg a Distribution of body sodium ECF 4 5% Serum Nat concentration :135~145mmol/L ■食物提供:№a2~4g/24h,肾排出量:100~140mmo(3g)/24h, 粪便排出>10mg/24h。 肾排钠特点:“多吃多排,少吃少排,不吃不排”。 《汘液是低渗溶液,含钠量约10~7σmmo:肠道消化液富含№aHCO3》
■食物提供:Na 2~4g/ 24h,肾排出量:100~140mmol(3g)/24h, 粪便排出 >10mg/24h。 ■肾排钠特点:“多吃多排,少吃少排,不吃不排” 。 《汗液是低渗溶液,含钠量约10~70mmol/L;肠道消化液富含NaHCO3》 四、钠的平衡调节(Balance of sodium) (一)人体钠的含量与分布(Content& distribution of body sodium ) ■Content of sodium :58mmol/kg,Total body sodium:60~80g/ 60kg. ■Distribution of body sodium: ECF 45% ICF 10% Bone 45% Serum Na+ concentration: 135~145mmol/L 水、电解质紊乱
水、电解质乱 (二)钠的生理功能 ( Functions of sodium in body) 12 Maintaining the osmolality of the ECF; Effect to water distribution between the ICF and ECF. 3. Participates in acid-base balance 4. Maintaining the normal neuromuscular irritability participates in action potential formation
(二)钠的生理功能 (Functions of sodium in body) 1.Maintaining the osmolality of the ECF; 4.Maintaining the normal neuromuscular irritability, participates in action potential formation. 3.Participates in acid-base balance; 2.Effect to water distribution between the ICF and ECF; 水、电解质紊乱
(三)体液的交换( Exchange of body fluids) 1.血浆和细胞间体液的交换平衡 Hydrostatic pressure and osmotic pressure are the forces that determine transport of fluid in and out of capillaries 2.细胞内外液体的交换平衡 Exchange of fluid between the cytoplasm and the interstitial space is driven by osmotic gradients 3.体内外液体(钠、水)的交换平衡 By the hypothalamic thirst mechanism, by alterations GFR, and by several hormones (1)渴感( Thirst) 血清钠浓度↑渴中枢(+)- hirst 有效循环血量↓、AGT↑ Water intake↑ECF↑
(三)体液的交换(Exchange of body fluids) 1.血浆和细胞间体液的交换平衡 Hydrostatic pressure and osmotic pressure are the forces that determine transport of fluid in and out of capillaries. (1)渴感(Thirst) 血清钠浓度↑ 口渴中枢(+) Thirst 有效循环血量↓、AGTII ↑ Water intake↑ ECF↑ 3.体内外液体(钠、水)的交换平衡 By the hypothalamic thirst mechanism, by alterations GFR, and by several hormones. 2.细胞内外液体的交换平衡 Exchange of fluid between the cytoplasm and the interstitial space is driven by osmotic gradients
水、电解质乱 (2)抗利尿激素( Antidiuretic hormone,ADH) 渗透性刺激、非渗透性激、其他因素导致ADH分泌增加 ●血浆晶体渗透压↑(>280mmoL)- Osmoreceptor(+) ●血容量或血压明显↓—8 baroreceptor(+) 精神紧张、剧痛、恶心、血浆AGT等— ADH output↑ Reabsorption of water from renal distal tubular fluid t 【ADH作用下远曲小管、集合管对水重吸收机制】 ADH+2受体(远曲小管、集合管上皮细胞管腔膜) 膜内腺苷酸环化酶活性↑ AtP-4 CAMP↑—细胞内蛋白激酶激活 管腔膜上水通道蛋白(AQP)↑、通透性↑ 远曲小管、集合管上皮细胞对水重吸收↑
(2)抗利尿激素( Antidiuretic hormone,ADH) 渗透性刺激、非渗透性刺激、其他因素导致ADH分泌增加。 ●血浆晶体渗透压↑(> 280mmol/L) Osmoreceptor(+) ●血容量或血压明显↓ Baroreceptor(+) ●精神紧张、剧痛、恶心、血浆AGTII↑等 ADH output↑ Reabsorption of water from renal distal tubular fluid↑ 【ADH作用下远曲小管、集合管对水重吸收机制】 ADH + V2受体(远曲小管、集合管上皮细胞管腔膜) 膜内腺苷酸环化酶活性↑ ATP cAMP ↑ 细胞内蛋白激酶激活 管腔膜上水通道蛋白(AQP)↑、通透性↑ 远曲小管、集合管上皮细胞对水重吸收↑ 水、电解质紊乱