Physiology Dep. Airlangga University Physiology of Cell, Body Fluids, Excitable tissue & Muscle Choesnan Effendi Physiology Dep. Airlangga University 2012
Episode Kedua
Cair Tubuh & Transport bahan melewati membran Body Fluids & Transport of substances through the cell membrane
Cair Tubuh Extracellular Intracellular Interstitial Plasma darah Transcellular
Volume % BB ( Berat Badan ) Indikator Total body water (cair tubuh total) 60 Deutrium ( D2O / 2H2O ), Tritium ( 3H2O ), Antipyrine Cair Ekstrasellular 20 Inulin *C 14 , Thiosulfate Cair Intrasellular 40 Total body water − Cair Ekstrasellular Plasma darah 5 Evans blue ( T- 1824 ) , 125I-Albumin Darah 7 – 8 51Cr-labeled red blood cells { Volume plasma darah : ( 100 % − Hct )} Cair Interstisial 15 Volume ekstrasellular − Volume plasma
Hematocrit Plasma darah Whole blood
X100 % = 36 – 45 % Volume Eritrosit Volume Darah = Hct
= PCV ( Packed Red Cell Volume ) HCT = Hematocrit = PCV ( Packed Red Cell Volume ) Adalah volume kumpulan erithrocytes yang dinyatakan dengan % terhadap volume darah keseluruhan
Beberapa cara masuk / keluarnya bahan melewati membran sel Interstitiel / Plasma darah Cytoplasma Osmosa Diffusi sederhana Diffusi fasilitasi Transport aktif Exocytosis / endocytosis
Pertukaran cairan didaerah kapiller
Ruang interstitiel Sitoplasma / sitosol Plasma darah
Fluid exchange : Arteriole capillary venule
Filtrasi / pertukaran cairan daerah kapiller Dipengaruhi oleh beberapa faktor : Tekanan onkotik plasma Tekanan onkotik interstisial Tekanan hidrostatik plasma Tekanan hidrostatik interstisial Tekanan hidrostatik plasma = tekanan darah
Total 7,3 28,0 Protein plasma Gram % P Tekanan kolloid osmotik = Tekanan onkotik Tekanan onkotik plasma darah Oleh karena adanya Protein plasma ( p ) Protein plasma Gram % P mm Hg Albumin 4,5 21,8 Globulin 2,5 6,0 Fibrinogen 0,3 0,2 Total 7,3 28,0
Dari ketiganya, jumlah terbanyak adalah ALBUMIN
25 – 1 – 28 + 8 = + 4 Sebagai contoh : Arteriole Venule Kapiller Interstisial Pint : 1 mm Hg ( hidrostatik ) Part : 37 mm Hg Pven : 17 mm Hg Ponkotik - int : 8 mm Hg Ponkotik - art ( ven ) : 28 mm Hg Pkap : 25 mm Hg NFP ( Net Filtration Pressure ) = Pkap – Pint - p kap + p int 25 – 1 – 28 + 8 = + 4 + ( positip ) : artinya cairan keluar dari kapiller, sisanya ini akan di absorbsi oleh limfe
NFP ( Net Filtration Pressure ) = Pkap – Pint - p kap + p int 25 – 1 – 28 + 8 = + 4 + ( positip ) : artinya cairan keluar dari kapiller, sisanya ini akan di absorbsi oleh limfe
Mengapa hypoproteinemia udema Bagaimana mengenai tekanan oncotic protein plasma ???
Starving Children in Nigeria
Udem akan terjadi apabila Bendungan vena : tumor, dekompensasi jantung kanan, bendungan aliran limfe Cairan dari intersitial yang menuju plasma < dibanding yang masuk
Tekanan osmotik plasma yang rendah Cairan dari intersitial yang menuju plasma << dibanding yang masuk O.K. Tekanan osmotik plasma yang rendah O.K. Kadar protein plasma yang rendah = HIPOPROTEINEMIA
Under nutrition : kurang gizi /rendah protein. HIPOPROTEINEMIA O.K. Under nutrition : kurang gizi /rendah protein. Sintesa protein ( terutama Albumin ) terganggu : a.l pada penyakit hati : cirrhosis hepatis Sekresi protein : yang seharusnya tidak terjadi , yaitu terjadi proteinuria ( pada nephrotic syndrome )
Tekanan osmotik plasma Berperanan untuk reabsorbsi kembali cairan yang dari interstisial
Beberapa cara masuk / keluarnya bahan melewati membran sel
Osmosa Diffusi sederhana Diffusi fasilitasi Transport aktif H2O yg bergerak dari larutan hipotonis kearah hipertonis Osmosa Diffusi sederhana Diffusi fasilitasi Transport aktif Bahan yang terlarut bergerak dari tekanan tinggi ketekanan rendah Seperti No. 2, menggunakan mediator (carrier system) Bahan yang terlarut bergerak dari tekanan rendah ketekanan tinggi, menggunakan mediator, energi ( ATP )
Osmosa Diffusi sederhana Diffusi fasilitasi Transport aktif Contoh : H2O CO2 , O2 , Ureum glukosa, asam amino Na, K, Ca Osmosa Diffusi sederhana Diffusi fasilitasi Transport aktif
Mediator = carrier system
Simple diffusion, facilitated diffusion & osmosis: are passive transport, without ATP Active transport, sodium potassium pump, calcium pump, exocytosis: are active, need ATP
Facilitated diffusion (also known as facilitated transport or passive-mediated transport) is a process of passive transport, facilitated by integral proteins (mediator). Without energy (ATP)
Water move from low concentration to high concentration Osmosis Osmosis (movement of water across membranes) depends on the relative concentration of solute molecules on either side of the membrane Water move from low concentration to high concentration
How do about erythrocytes if in: hypotonic solution isotonic solution hypertonic solution
Crenated / wrinkled ery in hypertonic medium Normal Ery structure in isotonic medium Swollen ery & rupture in hypotonic medium
Normal Ery structure in isotonic medium Crenated / wrinkled ery in hypertonic medium Swollen ery & rupture in hypotonic medium
Simple Diffusion Diffusion; the flow substances or matter from a higher concentration to a lower concentration
O2: Diffusion from alveoli into blood stream capillary CO2: Diffusion from blood capillary into alveoli
PO2 alv : 104 mmHG PcO2 alv : 40 mmHG PO2 cap : 40 mmHg PcO2 cap : 46 mmHg
Becomes: H+ + HCO3- (bicarbonate ion) at alveoli or at respiratory membrane O2 diffusion into blood capillary, then enter to the erythrocyte, bound by hemoglobin → HbO2 at tissue; tissue membrane and endothelium capillary CO2 diffusion into blood capillary, then enter to the erythrocyte, bound with H2O → H2CO3 →dissociation Becomes: H+ + HCO3- (bicarbonate ion)
, become H2CO3, H2CO3 dissociation, In blood stream: HCO3- (bicarbonate ion) flow out from erythrocyte into blood stream, to the capillary beds of respiratory membrane at respiratory membrane HCO3- (bicarbonate ion) flow in from blood stream into erythrocyte, then bind with H+ , become H2CO3, H2CO3 dissociation, Become H2O + CO2
at respiratory membrane CO2 flow out to blood (exit from erythrocyte) and then diffusion into alveoli lumen
→ to tissues and cells all the body In blood stream: O2 bound by hemoglobin → HbO2 → to tissues and cells all the body
at tissue O2 simple diffusion from HbO2 into cytosol, and then into mitochondria. Glucose move into cytosol by glucose transporter (facilitated diffusion)
Facilitated Diffusion Like simple diffusion, but requires interaction of a carrier protein that bind the molecules or ions to aids passage through the membrane Carrier protein = mediator or transporter
Facilitated diffusion (also known as facilitated transport or passive-mediated transport) is a process of passive transport, facilitated by integral proteins (mediator). Without energy (ATP)
Skeletal Muscle requires GLUT – 4 , Glut = Glucose transporter Skeletal Muscle requires GLUT – 4 , GLUT-4 stand-by in cytosol of muscle fiber, they ‘ll move into the membrane if insulin receptors are stimulated by insulin Glut = Glucose transporter is mediator/transporter of glucose enter into cytosol
Glucose – facilitated diffusion Insulin Receptor ( IR ) GLUT- 4 IRS-1 PI3 kinase translocation vesicle contains GLUT- 4 Cell membrane
Glucose enter into cytosol of skeletal muscle fiber by; Signal transduction by insulin Insulin activate insulin rec → form IRS1 IRS1 activates PI3-Kinase PI3-Kinase stimulate translocation vesicle, which contains GLUT-4 GLUT- 4 is mediator / transporter of glucose In skeletal muscle fiber
* Signal transduction by insulin ** Facilitated diffusion by GLUT- 4 There are 2 processes: * Signal transduction by insulin ** Facilitated diffusion by GLUT- 4
the Pumping of Solutes Against their Gradients Active Transport Active Transport is the Pumping of Solutes Against their Gradients
Active Transport is the Pumping of Solutes Against their Gradients 1. Cell must expend ATP/ energy to pump a molecule across a membrane 2. Performed by embedded proteins 3. Na-K Pump (sodium-potassium)- exchanges Na+ for K+ in animal cells when ATP changes protein conformation by transferring its terminal phosphate group to the transport protein
Active transport is the movement of a substance against its concentration gradient (from low to high concentration). active transport: energy-requiring, carrier-mediated transport system in which molecules can be moved across cell membrane against electrochemical gradient
K+ 140 mEq/L Na+ 14 mEq/L CL- 5 mEq/L Electrolyte inside & outside the cell membrane Resting Axon + + + + + + + – – – – – – – K+ 140 mEq/L Na+ 14 mEq/L CL- 5 mEq/L Na+ 142 mEq/L Cl- 120 mEq/L K+ 4 mE/L
3 molecules Na+ carried out into extracellular, changed by 2 molecules K+ (carried into cytosol)
Exocytosis
Exocytosis is the cellular process in which intracellular vesicles in the cytoplasm fuse with the plasma membrane and release or "secrete" their contents into the extracellular space
Exocytosis is the process by which cells excrete waste products and other large molecules from the cytoplasm
Exocytosis is the cellular process in which intracellular vesicles in the cytoplasm fuse with the plasma membrane and release or "secrete" their contents into the extracellular space Exocytosis is the process secretion substances into the extracellular space or into the blood stream.
Endocytosis is like phagocytosis Exocytosis is the reverse of endocytosis. Endocytosis is like phagocytosis
Exocytosis
Exocytosis & Endocytosis Transport Large Molecules 1. Exocytosis- transport vesicles migrate to plasma membrane & fuse & release contents 2. Endocytosis- large molecules enter cells within vesicles pinched inward from the membrane --> Phagocytosis- cell engulfs particles “cell eating” --> Pinocytosis- cell engulfs droplets of extracellular fluid “cell drinking”
The other way of transport across membrane
Cotransport: also known as coupled transport or secondary active transport, refers to the simultaneous or sequential passive transfer of molecules or ions across biological membranes. Symport Antiport
Several types transport across membrane (facilitated diffusion)
Symport
Sodium – glucose symport / Na-Glucose co-transport
or called IONS EXCHANGE Antiport An antiporter (also called exchanger or counter-transporter) is an integral membrane protein involved in secondary active transport of two or more different molecules or ions (i.e., solutes) across a phospholipid membrane such as the plasma membrane in opposite directions. or called IONS EXCHANGE
Na+ Glucose Ca++ Amino acid
For example, the Na+/Ca2+ exchanger, used by many cells to remove cytoplasmic calcium, exchanges one calcium ion for three sodium ions
the Na+ - Ca2+ exchanger (transporter)
The other example Na+ - H+ antiport
( Phosphatidyl Inositol 3’ kinase ) Contoh transduksi signal oleh insulin yang diikuti diffusi fasilitasi glukosa melalui GLUT - 4 GLUT – 4 : Glucose transporter – 4 PI-3 kinase : ( Phosphatidyl Inositol 3’ kinase ) Menyebabkan translokasi vesikel yang berisi GLUT – 4 menuju sel membran
Diffusi fasilitasi glukosa Insulin Receptor ( IR ) GLUT- 4 IRS-1 PI3 kinase Translokasi vesikel yang berisi GLUT- 4 Membran sel otot
Apa beda : Diffusi fasilitasi dengan Transport aktif ?
Acidosis ? Alkalosis ?
terlalu asam : disebut ASIDOSIS pH darah 7,35 – 7,45 terlalu asam : disebut ASIDOSIS terlalu basa / alkali : disebut ALKALOSIS Diare yang berlebihan ( gastro-enteritis ) pada anak dapat menimbulkan dehidrasi yang disertai asidosis o.k. Kehilangan cairan ( H2O ) + bikarbonat ( HCO3 )
Sodium – glucose symporter / Na-Glucose cotranspor
Resume Cair Tubuh & Transport bahan melewati membran Komposisi cair tubuh Cara pengukuran Pertukaran cairan didaerah kapiller Mekanisme terjadinya udem Pengertian osmosa, diffusi, diff fasilitasi, aktif transport
Modul / P. R. : Seorang ibu sedang membaca buku ilmiah populer, ada artikel yang menyebutkan bahwa sel pada manusia dapat membelah diri, juga artikel tersebut tertulis bahwa chromosome pria dan wanita berbeda, selanjutnya artikel itu menyebutkan bahwa tempat produksi energi terjadi didalam sel. Si ibu tersebut kesulitan memahami isi buku tersebut, kemudian bertanya pada anaknya, yang kebetulan kuliah di Universitas Airlangga.
Pertanyaannya : Bagaimana cara suatu sel dapat membelah diri ? Chromosome itu apa ? Dimana tempatnya, tersusun oleh apa, berapa jumlahnya, apakah berbeda antara pria dan wanita ? Apa yang dimaksud produksi energi didalam sel ?
Seorang anak wanita umur 12 tahun – siswa SD Kelas 6 akan menghadapi Ujian Nasional, belajar mengenai Biologi. Si anak bertanya pada ibunya, orang yang sedang berjalan dan berlari apakah membutuhkan sumber energi, darimana sumber energi tersebut. Kalau dari makanan bagaimana makanan tersebut bisa memberi energi tubuh orang yang sedang berjalan dan berlari tersebut. Ibunya kesulitan untuk menjawab dan menjelaskan, kemudian bertanya pada kakak anak tersebut yang sedang Kuliah di UNAIR
Pertanyaannya : Organ apa yang aktif sehingga seseorang dapat berjalan dan berlari. Bagaimana mekanismenya sehingga makanan dapat digunakan sebagai sumber energi sehingga dapat sampai ke sel-sel organ tersebut. Apakah glukosa dapat digunakan sebagai sumber energi ? Kalau bisa bagaimana caranya masuk kedalam sel ?
Sugar Crystals This electron microscope image of raw cane sugar reveals the shape of sugar crystals.
Sugar = sucrose Glucose – fructose
To Be Continued
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