1 / 51

Welcome to SPEP 2009!

Welcome to SPEP 2009!. The University of Cincinnati Heather Hale Elise Demitrack. Getting to know you…. Name School Field of interest. Key Terms. Physiology Study of Organ function Regulation/Interaction of organ systems Homeostasis

almira
Download Presentation

Welcome to SPEP 2009!

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Welcome toSPEP 2009! The University of Cincinnati Heather Hale Elise Demitrack

  2. Getting to know you… • Name • School • Field of interest

  3. Key Terms • Physiology • Study of Organ function • Regulation/Interaction of organ systems • Homeostasis • Body performs functions to maintain constituents of extracellular fluid • Ability to maintain constant internal environment • “Steady-state” (equal mixing)

  4. Units • Mass % (g%) = gram amount per 100 mL (1dL) • Equivalent (Eq) = gram amount of one mole of a substance divided by it’s valence • i.e. 1Eq of Ca2+ is 40 gm / 2 • Osmoles = # particles released into solution when solute is dissolved in H2O • Osmolar = 1 Osmole/mole dissolved in 1L H2O • Osmolal = 1 Osmole/mole dissolved in 1kg H2O • One gram-molecular weight of any substance represents and consists of 6 x 1023 molecules

  5. Physiology I Membrane PhysiologyHeather HaleJune 23, 2009

  6. Head group Hydrocarbon tail The Plasma Membrane • Lipid bilayer • Key Constituents: • Phospholipids • Amphipathic (polar head & non-polar tails) • Fluidity • Cholesterol • Rigidity • Glycoproteins (protein + carbohydrate) • “Float” throughout bilayer • Forms receptor substances (glycocalyx) http://www.cytochemistry.net/Cell-biology/membrane_intro.htm

  7. Crucial for creating an electrochemical gradient! Membrane Permeability • Selective! • Simple Diffusion • Rate depends on molecule’s: • Lipid solubility • Size • Charge • Assisted by: • Ion channels • Transporters http://en.wikipedia.org/wiki/Semipermeable_membrane

  8. Selective Permeability

  9. Plasma Membrane Proteins • Integral • Permanently associated with membrane • Transmembrane: spans entire bilayer • Peripheral • Associate with bilayer or another protein • Temporarily attached www.ultranet.com/~jkimball/BiologyPages/C/CellMembranes.html

  10. Summary: Plasma Membrane

  11. Membrane Proteins: Channels • Spans bilayer to form “pore” • Moves substances across bilayer • Gating: • Selectivity! • Ligand-gated • Mechanically gated • Voltage-gated Passive transport!

  12. “Carrier” proteins Transport specific substance across bilayer (selective!) Channel changes shape/orientation Membrane proteins: Transporters Active transport! http://phy.asu.edu/phy598-bio/D5%20Notes%2006.htm

  13. Types of Transporter Proteins Symport video http://www.biologie.uni-hamburg.de/b-online/library/biology107/bi107vc/fa99/terry/images/SymporA.gif http://library.thinkquest.org/C004535/cell_membranes.html

  14. Membrane Proteins: Enzymes • Protein active site (intracellular or extracellular) catalyzes reactions Catalyze reactions inside/outside cell Associated with membrane to increase efficiency http://www.biochem.arizona.edu/classes/bioc462/462b/Miesfeld/Photosynthesis.html

  15. Examples of Membrane Proteins • Channels: Ca2+ and Na2+ channels • Transporters: • Proteins transporters • Glucose transporters • Enzymes: Mitochondrial membrane proteins

  16. Movement Across Plasma Membrane • Transport of material across bilayer • Can be direct (non-facilitated) • Some requires proteins: • Diffusion (facilitated) • Active transport (energy!)

  17. No proteins required! Passive Movement • No cell energy required! • Simple diffusion • [high] [low] • Based on molecule‘s properties • Gases, nutrients, ions • Limited by diffusion rate of molecule! http://www.indiana.edu/~phys215/lecture/lecnotes/diff.html

  18. H2O moves toward compartment with high [solute] Passive Movement of Water Movement of H2O across cell Moves from [H2O]high [H2O]low H2O keeps osmotic pressure equal across membrane http://www.indiana.edu/~phys215/lecture/lecnotes/diff.html

  19. Solutions & Osmotic Pressure • Solutions • Isotonic: equal [solute] inside/outside • Hypotonic: low [solute]; H2O moves out • Hypertonic: high [solute]; H2O moves in • Osmotic Pressure • Required to stop osmotic H2O movement • Determined by # particles/unit volume • Osmole = # particles in 1 gram (MW) of un-dissociated solute

  20. Pressure & Water Movement H2O moves from Phigh to Plow • Influenced by two forces • Hydrostatic pressure: caused by gravity on a column of fluid • Hydraulic pressure: caused by action of a pump (active!) • Osmotic pressure = only pressure to initiate water flow in/out of cell

  21. Osmotic Pressure ECF and ICF have [osmotic] = 300 mOs/L • Calculated osmotic pressure (π = CsRT) • Cs = osmolar concentration • R = universal gas constant • T = absolute temperature • (RT = 22.4 ATM/osmole at 37˚C) • Effective osmotic pressure: • Depends on permeability of membrane to specific solute

  22. Osmotic Pressure • Fig A: semipermeable membrane • Solute cannot pass • Pos will equal the Phydrostatic as water flow into tube • Fig B: solute-permeable membrane • Solute equilibrates • Effective Pos of solution is zero

  23. Passive Movement: Facilitated • Examples: • Glucose transport • K+, Na+, Cl- transport Requires membrane proteins! Forms water-filled pore Solutes move down [conc] gradient (high  low)

  24. Active Movement: 1˚ Transport • Requires cellular energy! • Transporters bind ATP • Hydrolysis of ATP to ADP + Pi • Drives transport of solute against concentration gradient! • Examples: • Na+/K+ ATPase pump • Ca2+ ATPase

  25. Active Movement: Na+/K+ Pump video http://images.google.com/imgres?imgurl=http://student.ccbcmd.edu/~gkaiser/biotutorials/eustruct/images/sppump.gif&imgrefurl=http://student.ccbcmd.edu/~gkaiser/biotutorials/eustruct/sppump.html&h=290&w=290&sz=515&hl=en&start=1&um=1&tbnid=RE2RGHk1UT

  26. Uses energy of a “driving ion” moving down [conc] gradient to move a 2nd molecule against [conc] gradient Driving ion usually Na+ using gradient created by the Na+/K+ pump Active Movement: 2˚ Transport Examples: -Na+/Ca2+ exchanger -Na+/glu transporter http://courses.cm.utexas.edu/jrobertus/ch339k/overheads-2/ch12_Na-gluc-trans

  27. Active Movement: Bulk Transport • Endocytosis: transport into cell • Phagocytosis = ingest large particles • Pinocytosis = ingest small vesicles • Receptor-mediated ingestion • Exocytosis: transport out of cell http://upload.wikimedia.org/wikipedia/commons/thumb/1/1a/Endocytosis

  28. Physiology I Body Fluid SpacesHeather HaleJune 24, 2008

  29. Body Fluid Spaces • The human body is mostly water • Total H2O content of the human body = 45-60% of body weight • Total Body Water (% of body weight) • Males: 60% (ages 17-34) 54% (ages 50+) • Females: 55% (ages 17-34) 46% (ages 50+)

  30. Major Body Fluid Spaces • Two major “compartments” • Intracellular fluid (ICF): • fluid contained within cells • Accounts for 40% of body fluid weight • Extracellular fluid (ECF): • fluid outside of the cell • Accounts for 20% of body fluid weight • Total body water = ICF + ECF

  31. i.e. 70kg × 0.4 = 28 L of ICF fluid Major Body Fluid Spaces • The 60, 40, 20 rule • 60 = All fluid is 60% of total body weight • 40 = ECF is 40% of body weight • 20 = ICF is 20% of body weight

  32. Major Body Fluid Spaces • ECF is subdivided even further: • Plasma space = 5% of total body weight • Interstitial fluid (ISF) = 15% of total body weight • ISF = ultrafiltrate of plasma

  33. Ratio of red blood cell (RBC) volume to whole blood volume Hct is typically 40% of whole blood volume Whole blood volume = 7-9% of body weight (about 6 L) Body Fluids: Hematocrit (Hct) Hct = (vol)RBC (vol)whole blood 1 - Hct = (vol)plasma (vol)whole blood

  34. Learn these values! Body Fluids: Cations/Anions • Total [Osmolar] = 280-296 mOs/L • Na+ = 13-145 mEq/L • Cl- = 100-106 mEq/L • Ca2+ = 4.3-5.3 mEq/L • Glucose = 70-110 mg% • Total protein = 6-8 g%

  35. Body Fluids: Cations/Anions • ECF is high in Na+ & Cl- • ICF is high in K+

  36. C1 V1 = C2 V2 V2 = (C1 V1) / C2 Body Fluid Space Measurements • To estimate the size of body fluid spaces, use a dye indicator dilution • Based on conservation of mass principle • [conc]  vol = mass • Only applicable during steady-state • No loss/gain of substance during measurement

  37. Body Fluid Spaces: Fick Principle • If some solute is lost/gained: • C1 V1 = C2  V2 (+ amount gained) • orC1 V1 = C2  V2 (- amount lost) • Analysis represents Fick Principle • Commonly used to measure blood flow or cardiac output

  38. 3 component system (plasma, ISF, ICF) Inject substances into plasma Assumptions Equal amnt x, y, z x, y, z not present before injection Body Fluid Space Measurements

  39. Body Fluid Space Measurements • Capillaries • separate plasma/ISF • Permeable to y and z but not to x • Cell membrane • Separate ISF/ICF • Permeable to z only

  40. Body Fluid Space Measurements • Volume distribution of x = plasma • Volume distribution of y = plasma + ISF • Volume distribution of x = ECF + ISF

  41. Body Fluid Spaces: Markers • Plasma fluid markers (“x”) • Do not cross capillaries • Examples: • Radioiodinated serum albumin • Evan’s Blue (dye that binds albumin) • RBCs with radioactive iron or chromium

  42. Body Fluid Spaces: Markers • ECF markers (“y”) • Represents plasma + ISF • Cross capillary but not cell membrane • Examples: • Isotopic Cl- or Na+ • Inulin • Mannitol

  43. Body Fluid Spaces: Markers • Markers for total body water (“z”) must be permeable to both capillaries and cell membranes • Examples: • 3H water (tritiated “heavy” water) • Urea (carbon labeled, or tritiated) • Lipid soluble substances

  44. Capillary Fluid Movement • Capillaries separate plasma from ISF • ECF ions move across capillaries between plasma and ISF • But, proteins are restricted to plasma • Creates osmotic pressure ~15-25 mmHg • This is the colloid osmotic pressure

  45. Starling’s Law of the Capillary • Principle of pressure differences • Pressures: • Reabsorptive forces: • Capillary colloid osmotic pressure • ISF hydrostatic pressure • Filtration forces: • Capillary blood pressure • ISF colloid osmotic pressure FM = Kf [(BPcap + COPISF) - (COPcap + HPISF)]

  46. Filtration Reabsorption Reabsorption Filtration Capillary Fluid Movement FM = Kf [(BPcap + COPISF) - (COPcap + HPISF)]

  47. Email: heather.hale55@gmail.com Lab location: Health professionals Building Room 234 (off of Eden Ave, across from Eden Garage and MSB) Contact Info

  48. Supplementary Figures

  49. Supplementary Figures

  50. Supplementary Figures

More Related