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Mosebetsi oa Platelet Physiological

Li-platelet (thrombocyte) ke likotoana tse nyane tsa cytoplasm tse lokollotsoeng ho cytoplasm ea Megakaryocyte e holileng mokong oa masapo.Le hoja Megakaryocyte e le palo e fokolang ea lisele tsa hematopoietic mokong oa masapo, e leng karolo ea 0.05% feela ea palo eohle ea lisele tsa 'mele oa masapo, liplatelete tseo li li hlahisang li bohlokoa haholo bakeng sa mosebetsi oa' mele oa hemostatic.Megakaryocyte ka 'ngoe e ka hlahisa liplatelete tse 200-700.

 

 

Palo ea liplatelete tsa motho e moholo ea tloaelehileng ke (150-350) × 109/L.Li-platelet li na le mosebetsi oa ho boloka botšepehi ba marako a methapo ea mali.Ha palo ea liplatelete e fokotseha ho 50 × Ha khatello ea mali e le ka tlase ho 109 / L, ts'oaetso e nyane kapa khatello e eketsehileng ea mali e ka baka matheba a stasis ea mali letlalong le submucosa, esita le purpura e kholo.Lebaka ke hore li-platelet li ka lula leboteng la vascular ka nako leha e le efe ho tlatsa likheo tse siiloeng ke lisele tsa endothelial cell detachment, 'me li ka kopanya lisele tsa vascular endothelial, tse ka' nang tsa phetha karolo ea bohlokoa ho boloka botšepehi ba lisele tsa endothelial kapa ho lokisa lisele tsa endothelial.Ha liplatelete li fokola haholo, ho thata ho phetha mesebetsi ena ’me ho na le tšekamelo ea ho tsoa mali.Li-platelet maling a potolohang hangata li maemong a "emeng".Empa ha methapo ea mali e senyehile, liplatelete li kenngoa ts'ebetsong ka ho kopana holimo le ketso ea lintlha tse itseng tsa coagulation.Li-platelet tse sebetsang li ka lokolla letoto la lintho tse hlokahalang bakeng sa ts'ebetso ea hemostatic le ho sebelisa mesebetsi ea 'mele e kang ho khomarela, ho kopanya, ho lokolla le ho bapatsa.

Platelet e hlahisang Megakaryocyte le eona e tsoa liseleng tsa stem tsa hematopoietic mokong oa masapo.Lisele tsa "hematopoietic stem" li qala ho arohana ka lisele tsa megakaryocyte progenitor, tse tsejoang hape e le colony forming unit megakaryocyte (CFU Meg).Li-chromosome tse khubung ea sethala sa lisele tsa progenitor hangata li na le 2-3 ploidy.Ha lisele tsa progenitor li le diploid kapa tetraploid, lisele li na le bokhoni ba ho ata, kahoo ena ke sethala ha mela ea Megakaryocyte e eketsa palo ea lisele.Ha lisele tsa progenitor tsa megakaryocyte li tsoela pele ho aroloa ho 8-32 ploidy Megakaryocyte, cytoplasm e ile ea qala ho khetholla 'me tsamaiso ea Endomembrane ea phethoa butle-butle.Qetellong, ntho ea lera e arola cytoplasm ea Megakaryocyte libakeng tse ngata tse nyenyane.Ha sele ka 'ngoe e arohane ka ho feletseng, e fetoha platelet.Ka bonngoe, li-platelet li theoha ho Megakaryocyte ka lekhalo le pakeng tsa lisele tsa endothelial tsa lerako la sinus la mothapo ebe li kena maling.

Ho ba le thepa e fapaneng ka ho felletseng ea immunological.TPO ke glycoprotein e hlahisoang haholo ke liphio, e nang le boima ba molek'hule bo ka bang 80000-90000.Ha liplatelete maling li fokotseha, khatello ea TPO maling ea eketseha.Mesebetsi ea ntlha ena ea taolo e kenyelletsa: ① ho matlafatsa motsoako oa DNA liseleng tsa pele le ho eketsa palo ea lisele tsa polyploid;② E susumetsa Megakaryocyte ho etsa protheine;③ Eketsa palo eohle ea Megakaryocyte, e leng se hlahisang tlhahiso e eketsehileng ea platelet.Hona joale, ho lumeloa hore ho ata le ho arohana ha Megakaryocyte ho laoloa haholo-holo ke lintlha tse peli tsa taolo ka mekhahlelo e 'meli ea phapang.Lilaoli tsena tse peli ke megakaryocyte Colony-stimulating factor (Meg CSF) le Thrombopoietin (TPO).Meg CSF ke ntho e laolang haholo-holo e sebetsang sethaleng sa lisele tsa progenitor, 'me karolo ea eona ke ho laola ho ata ha lisele tsa megakaryocyte progenitor.Ha palo eohle ea Megakaryocyte mokong oa masapo e fokotseha, tlhahiso ea ntlha ena ea taolo ea eketseha.

Ka mor'a hore liplatelete li kene maling, li na le mesebetsi ea 'mele feela matsatsing a mabeli a pele, empa bophelo ba bona bo tloaelehileng bo ka ba matsatsi a 7-14.Mesebetsing ea physiological hemostatic, liplatelete ka botsona li tla qhalana ebe li lokolla lintho tsohle tse sebetsang kamora ho kopana;E ka boela ea kenyelletsa liseleng tsa vascular endothelial.Ntle le botsofali le timetso, liplatelete le tsona li ka jeoa nakong ea ts'ebetso ea tsona ea 'mele.Liplatelete tse tsofetseng li koaheloa ke spleen, sebete le lisele tsa matšoafo.

 

1. Ultrastructure ea liplatelete

Tlas'a maemo a tloaelehileng, liplatelete li hlaha e le li-discs tsa convex hanyenyane mahlakoreng ka bobeli, ka bophara ba bophara ba 2-3 μ m.Ka karolelano molumo ke 8 μ M3.Liplatelete ke lisele tse nang le nucleated tse se nang sebopeho se khethehileng tlas'a microscope ea optical, empa ultrastructure e rarahaneng e ka bonoa tlas'a microscope ea elektronike.Hona joale, sebopeho sa li-platelet ka kakaretso se arotsoe ka libaka tse potolohileng, sebaka sa gel sol, sebaka sa Organelle le sebaka se khethehileng sa membrane system.

Sebaka se tloaelehileng sa platelet se boreleli, 'me ho na le likarolo tse nyenyane tsa concave tse bonahalang,' me ke tsamaiso e bulehileng ea canalicular (OCS).Sebaka se potolohileng sebaka sa platelet se entsoe ka likarolo tse tharo: lera le ka ntle, lesela la yuniti, le sebaka sa submembrane.Seaparo sena haholo-holo se entsoe ka li-glycoprotein tse sa tšoaneng (GP), tse kang GP Ia, GP Ib, GP IIa, GP IIb, GP IIIa, GP IV, GP V, GP IX, joalo-joalo E etsa mefuta e sa tšoaneng ea li-receptor tse khomarelang 'me e ka kopanya. ho TSP, thrombin, collagen, fibrinogen, joalo-joalo. Ho bohlokoa hore liplatelete li kenye letsoho ho coagulation le taolo ea 'mele ea ho itšireletsa mafung.Lera la yuniti, le tsejoang hape e le lera la plasma, le na le likaroloana tsa protheine tse kentsoeng ka har'a lipid bilayer.Palo le kabo ea likaroloana tsena li amana le ho khomarela platelet le mosebetsi oa ho kopanya.Lera le na le Na + - K + - ATPase, e bolokang phapang ea mahloriso ea ion ka hare le ka ntle ho lera.Sebaka sa submembrane se pakeng tsa karolo e ka tlaase ea lera la yuniti le lehlakoreng le ka ntle la microtubule.Sebaka sa Submembrane se na le likhoele tsa submembrane le Actin, tse amanang le ho khomarela le ho kopanya liplatelete.

Li-microtubules, microfilaments le submembrane filaments le tsona li teng sebakeng sa sol gel ea liplatelete.Lintho tsena li etsa skeleton le contraction system ea liplatelete, tse bapalang karolo ea bohlokoa ho holofatseng ha liplatelete, ho lokolloa ha likaroloana, ho otlolla le ho honyela ha lehlo.Li-microtubules li entsoe ka Tubulin, e etsang karolo ea 3 lekholong ea protheine ea platelet.Mosebetsi oa bona o ka sehloohong ke ho boloka sebopeho sa liplatelete.Li-microfilaments li na le Actin, e leng protheine e ngata ka ho fetisisa liplateleteng 'me e nka 15% ~ 20% ea kakaretso ea protheine ea platelet.Li-submembrane filaments haholo-holo ke likaroloana tsa fiber, tse ka thusang Actin-tlamang protheine le Actin crosslink ho etsa dingata hammoho.Ka lebaka la boteng ba Ca2 +, actin e sebelisana le prothrombin, contractin, protheine e tlamang, co actin, myosin, joalo-joalo ho phethahatsa phetoho ea sebopeho sa platelet, sebopeho sa pseudopodium, contraction ea sele le liketso tse ling.

Letlapa la 1 Letlapa le ka Sehloohong la Membrane Glycoproteins

Sebaka sa Organelle ke sebaka seo ho sona ho nang le mefuta e mengata ea Organelle ka har'a li-platelet, tse nang le tšusumetso ea bohlokoa mosebetsing oa li-platelet.Hape ke sebaka sa lipatlisiso tsa bongaka ba sejoale-joale.Likarolo tsa bohlokoa ka ho fetisisa sebakeng sa Organelle ke likaroloana tse fapaneng, tse kang α Particles, particles tse teteaneng (δ Particles) le Lysosome ( λ Particles, joalo-joalo, bona Lethathamo la 1 bakeng sa lintlha tse ling.α Granules ke libaka tsa polokelo ea liplatelete tse ka hlahisang liprotheine.Ho na le tse fetang leshome platelet ka 'ngoe α Particles.Lethathamo la 1 le thathamisa feela likarolo tse batlang li le kholo, 'me ho latela lipatlisiso tsa mongoli, ho fumanoe hore α Ho na le maemo a fetang 230 a lintlha tse tsoang ho platelet (PDF) tse teng ka har'a granules.Tekanyo e teteaneng ea likaroloana α Likaroloana li nyane hanyane, ka bophara ba 250-300nm, 'me ho na le likaroloana tse teteaneng tse 4-8 ho platelet ka' ngoe.Hona joale, ho fumanoe hore 65% ea ADP le ATP li bolokiloe ka likaroloana tse teteaneng ka har'a li-platelet, 'me 90% ea 5-HT maling e boetse e bolokiloe ka likaroloana tse teteaneng.Ka hona, likaroloana tse teteaneng li bohlokoa bakeng sa ho bokellana ha platelet.Bokhoni ba ho lokolla ADP le 5-HT bo ntse bo sebelisoa ka bongaka ho lekola tšebetso ea secretion ea platelet.Ntle le moo, sebaka sena se boetse se na le mitochondria le Lysosome, eo hape e leng sebaka sa lipatlisiso lapeng le kantle ho naha selemong sena.2013 Nobel Prize in Physiology and Medicine e ile ea fuoa bo-rasaense ba bararo, James E. Rothman, Randy W. Schekman, le Thomas C. S ü dhof, bakeng sa ho sibolla liphiri tsa mekhoa ea lipalangoang tsa intracellular.Ho boetse ho na le masimo a mangata a sa tsejoeng ho metabolism ea lintho le matla liplatelete ka 'mele oa intracellular le Lysosome.

Sebaka se ikhethileng sa membrane se kenyelletsa OCS le dense tubular system (DTS).OCS ke tsamaiso e thata ea liphaephe tse entsoeng ke bokaholimo ba li-platelet tse theohelang ka hare ho li-platelet, tse eketsang haholo sebaka sa li-platelet tse amanang le plasma.Ka nako e ts'oanang, ke kanale ea kantle ho sele ea hore lintho tse fapaneng li kene liplatelete ebe li lokolla likarolo tse fapaneng tsa liplatelete.Pipe ea DTS ha e kopane le lefats'e le ka ntle 'me ke sebaka sa motsoako oa lintho tse ka har'a lisele tsa mali.