1 / 57

BLOOD COMPOSITION

BLOOD COMPOSITION. dr. Husnil Kadri , M.Kes Biochemistry Departement Medical Faculty Of Andalas University Padang. BIOSINTESIS HEMOGLOBIN (PORFIRIN). Struktur Porfirin. Porfirin adalah senyawa siklik yg dibentuk oleh 4 cincin pirol.

gerry
Télécharger la présentation

BLOOD COMPOSITION

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. BLOOD COMPOSITION dr. HusnilKadri, M.Kes Biochemistry Departement Medical Faculty Of Andalas University Padang

  2. BIOSINTESIS HEMOGLOBIN(PORFIRIN)

  3. Struktur Porfirin • Porfirin adalah senyawa siklik yg dibentuk oleh 4 cincin pirol. • Masing-masing cincin dihubungkan oleh 4 jembatan metenil (-HC=). • Sifat khas porfirin adalah atom nitrogennya mampu mengikat ion logam. • Contoh; - heme pada Hb mengikat Fe - klorofil pada tumbuhan hijau mengikat Mg

  4. Beberapa Hemoprotein Protein Fungsi - Hemoglobin mengangkut oksigen di dalam darah - Mioglobin menyimpan oksigen di dalam otot - Sitokrom c keterlibatan pada rantai transpor elektron - Sitokrom P450 hidroksilasi xenobiotik - Katalase degradasi hidrogen peroksida - Triptofan pirolase oksidasi triptofan

  5. SintesisHemediMitokondria • 85% sintesis heme terjadi dalam sel pembentuk eritrosit pada sumsum tulang • Heme disintesis dari suksinil KoA + glisin. • Piridoksal fosfat diperlukan untuk mengaktifkan glisin.

  6. Sintesis Heme di Mitokondria

  7. Pengaturan Sintesis Heme • Enzim regulator adalah ALA-sintase. • Heme bertindak sebagai regulator negatif (umpan balik negatif) sintesis enzim ALA- sintase. • Jika heme meningkat, maka sintesis ALA-sintase akan menurun.

  8. Porfiria • Merupakan gangguan genetik biosintesis heme. • Umumnya autosomal dominan, kecuali porfiria eritropoitik kongenital. • Gejala; - nyeri abdomen - gangguan neuropsikiatri - fotosensitifitas kulit - bila berat = prototipe manusia srigala

  9. Dasar Biokimia Porfiria Mutasi DNA Abnormalitas enzim pada sintesis heme Akumulasi ALA & PBG atau Akumulasi porfirinogen penurunan heme dlm sel & di kulit & jaringan tubuh Cairan tubuh Tanda &gejala Oksidasi spontan porfirinogen neuropsikiatrik menjadi porfirin Fotosensitifitas

  10. Terapi Porfiria • Hanya simptomatik. • Represor ALA-sintase; - glukosa - hematin (bentuk hidroksida dari heme) - b-karoten untuk fotosensitifitas - preparat tabir surya • Kontraindikasi; - preparat anestesi - alkohol - griseofulvin & barbiturat

  11. Fungsi Utama Darah 1. Respirasi; pengangkutan O2 dan CO2 2. Nutrisi; pengangkutan hasil absorpsi usus 3. Ekskresi; pengangkutan sisa metabolik ke ginjal, paru-paru, kulit, & usus

  12. Fungsi Utama Darah 4. Keseimbangan asam-basa 5. Keseimbangan air; antara sirkulasi darah dan jaringan 6. Pengaturan suhu tubuh 7. Pertahanan terhadap infeksi; oleh sel darah putih & antibodi

  13. Fungsi Utama Darah 8. Pengangkutan hormon & pengaturan metabolisme 9. Pengangkutan metabolit 10. Koagulasi

  14. Components of Whole Blood Plasma(55% of whole blood) Buffy coat:leukocyctes and platelets(<1% of whole blood) Formed elements Erythrocytes(45% of whole blood) Withdraw blood and place in tube Centrifuge 1 2 • Hematocrit • Males: 47% ± 5% • Females: 42% ± 5%

  15. Physical Characteristics of Blood • Average volume of blood: • 5–6 L for males; 4–5 L for females (Normovolemia) • Hypovolemia - low blood volume • Hypervolemia - high blood volume • Viscosity (thickness) - 4 - 5 (where water = 1) • The pH of blood is 7.35–7.45; x = 7.4 • Osmolarity = 300 mOsm or 0.3 Osm • This value reflects the concentration of solutes in the plasma • Salinity = 0.85% • Reflects the concentration of NaCl in the blood • Temperature is 38C, slightly higher than “normal” body temperature • Blood accounts for approximately 8% of body weight

  16. Components of Blood • 55% plasma • 45% cells • 99% RBCs • < 1% WBCs and platelets

  17. Blood Plasma • Blood plasma components: • Water = 90-92% • Proteins = 6-8% • Organic nutrients – glucose, carbohydrates, amino acids • Electrolytes – sodium, potassium, calcium, chloride, bicarbonate • Nonprotein nitrogenous substances – lactic acid, urea, creatinine • Respiratory gases – oxygen and carbon dioxide

  18. Formed Elements • Formed elements comprise 45% of blood • Erythrocytes, leukocytes, and platelets make up the formed elements • Only WBCs are complete cells • RBCs have no nuclei or organelles, and platelets are just cell fragments • Most blood cells do not divide but are renewed by cells in bone marrow

  19. Erythrocytes (RBCs) • Biconcave disc • Folding increases surface area (30% more surface area) • Plasma membrane contains spectrin • Give erythrocytes their flexibility • Anucleate, no centrioles, no organelles • End result - no cell division • No mitochondria means they generate ATP anaerobically • Prevents consumption of O2 being transported • Filled with hemoglobin (Hb) - 97% of cell contents • Hb functions in gas transport • Hb + O2 HbO2 (oxyhemoglobin) • Most numerous of the formed elements • Females: 4.3–5.2 million cells/cubic millimeter • Males: 5.2–5.8 million cells/cubic millimeter

  20. Erythrocytes (RBCs) Figure 17.3

  21. Erythrocyte Function • Erythrocytes are dedicated to respiratory gas transport • Hemoglobin reversibly binds with oxygen and most oxygen in the blood is bound to hemoglobin • Composition of hemoglobin • A protein called globin • made up of two alpha and two beta chains • A heme molecule • Each heme group bears an atom of iron, which can bind to one oxygenmolecule • Each hemoglobin molecule thus can transport four molecules of oxygen

  22. Structure of Hemoglobin Figure 17.4

  23. Hemoglobin • Satu mol. Hb dewasa (HbA) mempunyai; - 4 gugus heme - Setiap heme mengandung 1 ion Fe2+ - 4 subunit protein globin - Setiap subunit mengikat 1 mol. O2 - 1 mol. Globin mengikat 1 mol. CO2 • Subunit rantai terdiri dari 2 a dan 2 b; - a masing-masing=141 asam amino - b masing-masing = 146 asam amino

  24. Hemoglobin • Oxyhemoglobin – hemoglobin bound to oxygen • Oxygen loading takes place in the lungs • Deoxyhemoglobin – hemoglobin after oxygen diffuses into tissues (reduced Hb) • Carbaminohemoglobin – hemoglobin bound to carbon dioxide • Carbon dioxide loading takes place in the tissues

  25. WBC Anatomy and Types • All WBCs (leukocytes) have a nucleus and no hemoglobin • Granular or agranular classification based on presence of cytoplasmic granules made visible by staining • granulocytes are neutrophils, eosinophils or basophils • agranulocytes are monocyes or lymphocytes

  26. Differential WBC Count • Detection of changes in numbers of circulating WBCs (percentages of each type) • indicates infection, poisoning, leukemia, chemotherapy, parasites or allergy reaction • Normal WBC counts • neutrophils 60-70% (up if bacterial infection) • lymphocyte 20-25% (up if viral infection) • monocytes 3 - 8 % (up if fungal/viral infection) • eosinophil 2 - 4 % (up if parasite or allergy reaction) • basophil <1% (up if allergy reaction or hypothyroid)

  27. Neutrophils (Granulocyte) • Polymorphonuclear Leukocytes or Polys • Nuclei = 2 to 5 lobes connected by thin strands • older cells have more lobes • young cells called band cells because of horseshoe shaped nucleus (band) • Fine, pale lilac practically invisible granules • Diameter is 10-12 microns • 60 to 70% of circulating WBCs

  28. Eosinophils (Granulocyte) • Nucleus with 2 or 3 lobes connected by a thin strand • Large, uniform-sized granules stain orange-red with acidic dyes • do not obscure the nucleus • Diameter is 10 to 12 microns • 2 to 4% of circulating WBCs

  29. Basophils (Granulocyte) • Large, dark purple, variable-sized granules stain with basic dyes • obscure the nucleus • Irregular, s-shaped, bilobed nuclei • Diameter is 8 to 10 microns • Less than 1% of circulating WBCs

  30. Lymphocyte (Agranulocyte) • Dark, oval to round nucleus • Cytoplasm sky blue in color • amount varies from rim of blue to normal amount • Small cells 6 - 9 microns in diameter • Large cells 10 - 14 microns in diameter • increase in number during viral infections • 20 to 25% of circulating WBCs

  31. Lymphocytes • B cells - responsible for humoral immunity • T cells - responsible for cell mediated immunity • B cells responsible for production of antibodies • Receptor matches antigen • Cells multiply • Antibodies

  32. T cells • Cytotoxic T cells (Killer T cells) • Bind to cytotoxic cells (eg infected by virus) • Swell • Release toxins into cytoplasm • Helper T cells • Most numerous • Activate B cells, killer T cells • Stimulate macrophages • Suppressor T cells • Regulate activities of other cell types

  33. Monocyte (Agranulocyte) • Nucleus is kidney or horse-shoe shaped • Largest WBC in circulating blood • does not remain in blood long before migrating to the tissues • differentiate into macrophages • fixed group found in specific tissues • alveolar macrophages in lungs • kupffer cells in liver • wandering group gathers at sites of infection • Diameter is 12 - 20 microns • Cytoplasm is a foamy blue-gray • 3 to 8% o circulating WBCs

  34. Emigration & Phagocytosis in WBCs

  35. UNSUR SELULAR DALAM RESPON IMUN • Jalur limfoid yang membentuk limfosit dan subsetnya • Jalur mieloid yang membentuk sel-sel fagosit mononuklear & polimorfonuklear (PMN). PMN terdiri dari: neutrofil, eosinofil, basofil

  36. Platelets • Platelets are fragments of mega-karyocytes • Their granules contain serotonin, Ca2+, enzymes, ADP, and platelet-derived growth factor (PDGF) • Platelets function in the clotting mechanism by forming a temporary plug that helps seal breaks in blood vessels • Platelets not involved in clotting are kept inactive by Nitric Oxide (NO) and prostaglandins

  37. Protein Plasma - Bagian utama unsur padat dalam plasma. - Konsentrasi total protein plasma + 7-7,5 g/dl. - Berbagai protein plasma dapat dipisahkan menurut karakteristik kelarutannya. - Metode pemisahan tsb antara lain; 1. Salting-out (Na2SO4 23%, dll) 2. Elektroforesis

  38. Zone Electrophoresis of Plasma Proteins + - globulins albumin g b a1 a2 pI 6.0 5.6 5.1 4.7

  39. Protein Plasma • Sebagian besar disintesis di hepar. • Umumnya disintesis sbg preprotein pada poliribosom terikat membran. Preprotein akan mengalami modifikasi pascatranslasi. • Hampir semuanya berupa glikoprotein, kecuali albumin. • Bersifat polimorfisme (ciri bawaan pd populasi dgn sedikitnya 2 macam fenotipe). contoh; gol. Darah ABO

  40. Plasma Proteins • More than 200 • Most abundant • Albumin - 4-5 g/100 mL - g-globulins - ~1 g/100 mL • fibrinogen - 0.2-0.4g/100 mL

  41. Albumin - Merupakan protein utama dalam plasma. - Mempertahankan 75-80% tekanan osmotik. - Berfungsi mengikat berbagai macam ligand, seperti; asam lemak bebas, Ca, Cu, Zn, hormon steroid, bilirubin, metheme

  42. Albumin - Albumin juga dapat mengikat obat-an, seperti; sulfonamid, penisilin-G, dikumarol, aspirin - Penyakit hepar akan memperlihatkan rasio albumin/globulin yang menurun.

  43. Transferin • Adalah b1-globulin berbentuk glikoprotein yang disintesis di hepar. • Berfungsi sebagai alat transpor besi (Fe3+) untuk dibawa ke jaringan. • Jika besi tidak diikat oleh transferin, maka akan menjadi prooksidan.

  44. Ceruloplasmin • Protein ini adalah a2-globulin yang mengandung 90% Cu plasma. Tetapi 10% Cu terikat longgar pd albumin, sehingga mudah dilepas ke jaringan. • Ceruloplasmin mengandung ferroksidase yang mengkatalisis ion Fe2+ --> Fe3+, karena hanya ion Fe3+ yang mampu berikatan dgn apotransferin.

  45. g-Globulins • 20% of plasma proteins • “g” refers to electrophoretic mobility • Represents a group of proteins of variable structure • immunoglobulins • Main functional task is immunochemical • Antibodies - combine with specific antigens

  46. Imunoglobulin Plasma • Disintesis dalam sel plasma. • Sel plasma adalah turunan Sel-b yang mensintesis dan mensekresikan imuno- globulin sebagai respon terhadap pajanan berbagai antigen. • Semua imunoglobulin mengandung paling kurang 2 rantai ringan dan 2 rantai berat.

  47. Classes of Immunoglobulins • IgG – Identifies microorganisms for engulfment or lysis • IgE – Inhibits parasite invasion; involved in allergic reactions • IgD – Unknown • IgA – Basis for passive immunity provided by breast milk, agglutinates infectious agents in secretions outside the body, present in tears, mucous • IgM – Identifies microorganisms for engulfment or lysis

More Related