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Homeostasis of internal enviroment

Homeostasis of internal enviroment. Acid-base homeostasis. External environment of organism. 1865 Claude Bernard. Internal environment of the cells. External environment of organism.

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Homeostasis of internal enviroment

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  1. Homeostasis of internal enviroment Acid-base homeostasis

  2. External environment of organism 1865 Claude Bernard Internal environment of the cells

  3. External environment of organism i.e. temperature, volume, osmolarity, pH, ionic composition, O2, CO2 concentrations, concentration of glucose etc. 1865 Claude Bernard THEY ARE STAEDY AND INDEPENDENT ON FLOATING CONDITIONS OF EXTERNAL ENVIRONMENT AND ON VARIED LEVELS OF CELLULAR METABOLIC ACTIVITY Their properties must enable optimal functioning of cellular structures External environment of cells = internal environment

  4. Homeostasis - the ability or tendency of an organism or cell to maintain internal equilibrium by adjusting its physiological processes. External environment of organism i.e. temperature, volume, osmolarity, pH, ionic composition, O2, CO2 concentrations, concentration of glucose etc. 1932 Walter Cannon THEY ARE STAEDY AND INDEPENDENT ON FLOATING CONDITIONS OF EXTERNAL ENVIRONMENT AND ON VARIED LEVELS OF CELLULAR METABOLIC ACTIVITY Their properties must enable optimal functioning of cellular structures External environment of cells = internal environment

  5. Homeostatic system is able to maintain its essential variables within limits acceptable to its own structure in the face of unexpected disturbances. Homeostasis = dynamic self-regulation nearly „cybernetic“ definition in 1932 1932 Walter Cannon

  6. Homeostatic system is able to maintain its essential variables within limits acceptable to its own structure in the face of unexpected disturbances. Homeostasis = dynamic self-regulation nearly „cybernetic“ definition in 1932 1932 Walter Cannon Arturo Rosenblueth (disciple of W. Cannon)

  7. Homeostatic system is able to maintain its essential variables within limits acceptable to its own structure in the face of unexpected disturbances. Homeostasis = dynamic self-regulation nearly „cybernetic“ definition in 1932 1932 Walter Cannon Arturo Rosenblueth Nobert Wiener (disciple of W. Cannon) collaboration

  8. Homeostatic system is able to maintain its essential variables within limits acceptable to its own structure in the face of unexpected disturbances. Homeostasis = dynamic self-regulation nearly „cybernetic“ definition in 1932 1932 Walter Cannon 1948: N. Wiener: Cybernetics or Control and Communication in the Animal and the Machine Arturo Rosenblueth Nobert Wiener (žák W. Cannona) collaboration

  9. Homeostasis - the ability or tendency of an organism or cell to maintain internal equilibrium by adjusting its physiological processes. External environment of organism i.e. temperature, volume, osmolarity, pH, ionic composition, O2, CO2 concentrations, concentration of glucose etc. 1932 Walter Cannon THEY ARE STAEDY AND INDEPENDENT ON FLOATING CONDITIONS OF EXTERNAL ENVIRONMENT AND ON VARIED LEVELS OF CELLULAR METABOLIC ACTIVITY Their properties must enable optimal functioning of cellular structures External environment of cells = internal environment

  10. Homeostasis - the ability or tendency of an organism or cell to maintain internal equilibrium by adjusting its physiological processes. External environment of organism 1932 Walter Cannon intracellular fluid extracellular fluid Their properties must enable optimal functioning of cellular structures External environment of cells = internal environment

  11. Homeostasis - the ability or tendency of an organism or cell to maintain internal equilibrium by adjusting its physiological processes. External environment of organism 1932 Walter Cannon intracellular fluid extracellular fluid Their properties must enable optimal functioning of cellular structures Metabolism External environment of cells = internal environment

  12. Homeostasis - the ability or tendency of an organism or cell to maintain internal equilibrium by adjusting its physiological processes. External environment of organism 1932 Walter Cannon intracellular fluid extracellular fluid Their properties must enable optimal functioning of cellular structures Metabolism External environment of cells = internal environment

  13. Inputs Balance between input and output flow Storage ? Outputs retention ? depletion

  14. External environment of organism Balance estimation Concentrations extracellular fluid - ECF intracellular fluid - ICF Metabolism

  15. External environment of organism Balance estimation Concentrations plasma Lymph capillaries extracellular fluid -ECF interstitial fluid - ISF intracellular fluid - ICF Metabolism

  16. External environment of organism intravascular blood cells plasma Lymph fluid (part of ICF) capillaries capillaries extracellular fluid -ECF interstitial fluid - ISF intracellular fluid - ICF Metabolism

  17. External environment of organism intravascular blood cells plasma Lymph fluid (part of ICF) extracellular fluid -ECF capillaries capillaries transcellular fluid interstitial fluid - ISF intracellular fluid - ICF Metabolism

  18. External environment of organism GIT Lungs „exchangers“ Ledviny intravascular blood cells plasma Lymph fluid (part of ICF) extracellular fluid -ECF capillaries transcellular fluid interstitial fluid - ISF intracellular fluid - ICF Metabolism

  19. External environment of organism „exchangers“ GIT Lung Kidney intravascular blood cells plasma Lymph fluid (part of ICF) extracellular fluid -ECF Circulation capillaries „mixing“ transcellular fluid interstitial fluid - ISF intracellular fluid - ICF Metabolism

  20. External environment of organism GIT Lungs „exchangers“ Kidney intravascular blood cells plasma Lymph fluid (part of ICF) extracellular fluid -ECF Circulation capillaries „mixing“ transcellular fluid interstitial fluid - ISF intracellular fluid - ICF Metabolism

  21. External environment of organism CO2 H+ GIT Lungs „exchangers“ Kidney intravascular blood cells plasma Lymph fluid (part of ICF) extracellular fluid -ECF Circulation capillaries „mixing“ transcellular fluid interstitial fluid - ISF intracellular fluid - ICF ACID-BASE BALANCE Metabolism

  22. H+ + H2O H+ OH- H2O - OH- H2O H3O+ H2O + H3O+ H2O OH- - OH- H2O

  23. H2O H2O H2O H2O H2O H2O H2O H2O H2O H2O H2O H2O

  24. H2O H2O H2O H2O H2O H2O H3O+ H2O OH- H2O H2O H2O

  25. H2O H2O H2O H2O H2O H3O+ H2O H2O OH- H2O H2O H2O

  26. H2O H2O H3O+ H2O H2O H2O H2O H2O OH- H2O H2O H2O

  27. H2O H2O H3O+ H2O H2O H2O H2O H2O OH- H2O H2O H2O

  28. H2O H2O H2O H2O H2O H2O H3O+ H2O H3O++ H2O H2O + H3O+ H2O H2O H2O H2O H2O H2O OH- H2O H2O OH- + H2O H2O + OH-

  29. H2O H2O H2O H2O H2O H2O H2O H3O+ H3O++ H2O H2O + H3O+ H2O OH- H2O H2O H2O H2O H2O H2O H2O OH- + H2O H2O + OH-

  30. H2O H2O H3O+ H2O H2O H2O H2O H2O H3O++ H2O H2O + H3O+ H2O OH- H2O H2O H2O H2O H2O H2O H2O OH- + H2O H2O + OH-

  31. H2O H2O H2O H3O+ H2O H2O H2O H2O H3O++ H2O H2O + H3O+ H2O H2O H2O H2O H2O H2O H2O OH- H2O OH- + H2O H2O + OH-

  32. H2O H3O+ H2O H2O H2O H2O H2O H2O H3O++ H2O H2O + H3O+ H2O H2O H2O H2O H2O H2O H2O OH- H2O OH- + H2O H2O + OH-

  33. H2O H2O H2O H2O H2O H3O+ H2O H2O H3O++ H2O H2O + H3O+ H2O H2O H2O OH- H2O H2O H2O H2O H2O OH- + H2O H2O + OH-

  34. H3O+ H2O H2O H2O H2O H2O H2O H2O H3O++ H2O H2O + H3O+ H2O H2O H2O OH- H2O H2O H2O H2O H2O OH- + H2O H2O + OH-

  35. H2O H2O H2O H2O H3O+ H2O H2O H2O H3O++ H2O H2O + H3O+ H2O H2O H2O H2O H2O H2O H2O OH- H2O OH- + H2O H2O + OH-

  36. H+ H2O H2O OH- H2O

  37. H3O+ OH- pH= -log [H+] k1 [H+][OH-] K‘ = = k2 [H2O] H+ H2O OH- v1=k1[H2O] OH- H2O H+ + v2=k2[H+][OH-] pH = 7.4[H+] = 10-7,4 mol/l´= 40 nmol/l v1=v2 k1[H2O] =k2[H+][OH-] K‘ [H2O] = [H+][OH-] [H+] = 1,55 10-7 mol/l´= 155 nmol/l [H2O] = constant [OH-] = 1,55 10-7 mol/l´= 155 nmol/l Kw = [H+][OH-] = 2,4 10-14 mol2/l2 at 37°C

  38. OH- Buffer curve H2O H+ H+ HBuf pH Buf- H+ + Buf HBuf H+ + Buf HBuf Addition of OH- mmol/l Addition of H+ mmol/l -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7

  39. Practically complete reabsorbtion of HCO3- H+ excretion 60 mmol/24 h CO2 HCO3- H2CO3 TA+NH4+ H+ H2O A- 20 000 mmol/24 hod 60 mmol/24 hod Metabolic production of CO2 Metabolic production od strong acids

  40. A: Closed system - HCO3 CO2 1. Addition of strong acid (H+ ions) H2CO3 H+ H2O - CO2 HCO3 2. Consumption of bicarbonate and added H+ ions in buffer reaction H2CO3 3. Establishment of new equilibriom with increased concentrations of CO2 and H2CO3 H+ H2O

  41. A: Open system - HCO3 CO2 1. Addition of strong acid (H+ ions) H2CO3 H+ H2O - CO2 HCO3 H2CO3 H+ H2O

  42. - HCO3 CO2 24 mmol/l TA+NH4+ H2CO3 40 nmol/l (pH=7,40) H2O H+ 20 000 mmol/24 hod Metabolic production of CO2 60 mmol/24 hod Metabolic production od strong acids

  43. - HCO3 CO2 24 mmol/l TA+NH4+ H2CO3 40 nmol/l (pH=7,40) H2O H+ 20 000 mmol/24 hod Metabolic production of CO2 60 mmol/24 hod Metabolic production od strong acids

  44. - - dH+ = +1 mmol/l dHCO3 = +1 mmol/l - HCO3 CO2 24 mmol/l TA+NH4+ H2CO3 10-3 mol H+/l: pH=3! 40 nmol/l (pH=7,40) H2O H+ 20 000 mmol/24 hod Metabolic production of CO2 60 mmol/24 hod Metabolic production od strong acids

  45. - - dH+ = +1 mmol/l dHCO3 = +1 mmol/l - HCO3 CO2 24 mmol/l TA+NH4+ H2CO3 10-3 mol H+/l: pH=3! 40 nmol/l (pH=7,40) H2O H+ HBuf 20 000 mmol/24 hod Metabolic production of CO2 Buf -

  46. - dHCO3 = +1 mmol/l - HCO3 CO2 24 mmol/l TA+NH4+ H2CO3 43 nmol/l (pH=7,37) H2O H+ +1 mmol/l HBuf 20 000 mmol/24 hod dBuf - = -1 mmol/l Metabolic production of CO2 Buf -

  47. Buffering systems of the blood + + CO2 H2O H2CO3 H+ HCO3- HBuf H+ + Buf- H+ + Hb- HHb H+ + Alb- HAlb H+ + HPO42- H2PO4- non-bicarbonate buffers Buf = Hb + Alb + PO4-

  48. HCO3- CO2 H2CO3 H2O H+ HBuf Buf- Buffering reactions

  49. Bicarbonate buffer + + CO2 H2O H2CO3 H+ HCO3- Hendersson- Hasselbalch equation: [H+] = 24 . pCO2 / [HCO3-] or pH = 6.1 + log ( [HCO3-] / [H2CO3] ) = 6.1 + log ( [HCO3-] / 0.03 pCO2 )

  50. - HCO3 CO2 H2CO3 40 nmol/l (pH=7,40) H2O H+ HBuf Buf - Buffer Base (BB) BB =[HCO3-]+ [Buf -]

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