Maumbirwo uye Basa reMaplatelet
Maplatelet, kana kuti maplatelet eropa, zvidimbu zvidiki zvemasero zvinowanikwa muropa uye zvine chekuita nekuita kweropa kugomara (hemostasis). Izvi zvinhu zvakakosha muhurongwa hweropa hwemunhu, zvichiita basa guru mukumisa kubuda ropa uye kutanga kupora kwemaronda. Muchinyorwa chino, tichaongorora chimiro nemashandiro emaplatelet zvakadzama, pamwe nekukosha kwawo mukuchengetedza hutano hwemuviri wese.
Mavambo uye Kugadzirwa kwemaplatelet
Maplatelet anobva kumasero makuru anonzi megakaryocytes ari mumongo wemapfupa. Megakaryocytes masero makuru uye akaomarara, ane dhayamita inosvika 100 micrometers. Masero aya anogadzira maplatelet nekuburitsa zvidimbu zvidiki zve cytoplasm yavo muropa. Maitiro aya anodzorwa nezvinhu zvakasiyana-siyana zvekukura uye mahormone, kusanganisira thrombopoietin, iyo inokurudzira kugadzirwa kwemegakaryocyte uye kukura.
Kana yangogadzirwa, maplatelet anotenderera muropa kwemazuva angangoita manomwe kusvika gumi asati aparadzwa ne reticuloendothelial system, kunyanya mu spleen nechiropa. Kazhinji, huwandu hwemaplatelet muropa hunotangira pa150.000 kusvika 450.000 pa microliter. Kuwanda kwemaplatelet kushoma kunonzi thrombocytopenia, nepo kuwanda kwemaplatelet kunonzi thrombocytosis.
Maumbirwo ePlatelet
Maplatelet ane chimiro chakasiyana uye chakaoma kunzwisisa pasinei nehukuru hwawo hudiki, ane dhayamita iri pakati pe2 ne3 micrometer. Chimiro chawo chine zvikamu zvikuru zvakati wandei:
1. Plasma Membrane: Chikamu chekunze chemaplatelet, chine mareceptor emhando dzakasiyana-siyana dzemamorekuru ekutumira masaini, kusanganisira collagen, fibrinogen, uye zvinhu zvinokura. Chidimbu ichi chinotsigirawo maglycoprotein anoita basa guru mukuunganidzwa kwemaplatelet uye kunamatira pamadziro etsinga dzeropa dzakakuvara.
2. Cytoplasm: Chikamu chemukati meplatelet chine maorganelle akasiyana-siyana uye maumbirwo, anosanganisira mitochondria, lysosomes, uye granules. Magranules aya ane alpha granules, ane mapuroteni ecoagulation akadai sefibrinogen uye growth factors, uye dens granules, ane mamorekuru akadai seADP necalcium anoita basa guru mukushanda kwemaplatelet.
3. Cytoskeleton: Network yemapuroteni ari mumaplatelet anopa chimiro uye rutsigiro rwemakanika. Zvinhu zvikuru zvecytoskeleton iyi zvinosanganisira actin nema microtubules, izvo zvinobvumira maplatelet kuchinja chimiro chawo panguva yekushanda nekuungana.
4. Sisitimu Yekuvhura Mugero uye Sisitimu Yekutenderera Yakakora: Maumbirwo emukati memukati anoshanda mukuchengetedza nekuburitsa mamorekuru ekutumira masaini. Sisitimu yekunze kwemugero inotaurirana nekunze kwesero uye inobatsira mukuburitswa kwegranule zviri mukati, nepo sisitimu yekudzikira kwemugero ichiita basa mukuchengetedza calcium uye kudzora huwandu hwecalcium mumasero.
Basa remaplatelet
Maplatelet ane mabasa makuru akati wandei ane chekuita nekubvisa ropa mumuviri uye kuporesa maronda:
1. Kugadzirwa kwePlug yePlatelet
Kana tsinga yeropa ikakuvara, collagen ne tissue factor kubva mu exposed extracellular matrix zvinokurumidza kushanda maplatelet. Maplatelet akashandiswa anochinja chimiro, anonamira, uye anonamatira kumadziro etsinga akakuvara. Anotangawo kuburitsa zviri mukati mawo, kusanganisira coagulation factors uye mamwe ma signal molecules anokwezva maplatelet akawanda kunzvimbo yakakuvara.
Maitiro aya anoguma nekuumbwa kweplatelet plug yekutanga iyo inomisa kubuda ropa kwenguva pfupi. Iri ndiro danho rekutanga mukutanga kwe hemostasis, iyo inodzivirira kurasikirwa kweropa rakawanda kusvika nzira dzechipiri dzekuvhara ropa dzave kuumba kugadzika kwakasimba.
2. Kuburitswa kweVagadziri veMakemikari
Kana yatanga kushanda, maplatelet anoburitsa zvinhu zvakasiyana-siyana zvinobatanidza makemikari kubva mumagranules awo. Alpha granules inoburitsa mapuroteni akadai sefibrinogen, platelet growth factor (PDGF), coagulation factors, kininogen, uye vWf (von Willebrand factor), izvo zvinobatsira mukuunganidza maplatelet uye kugadzikana kwemaplatelet. Dens granules dzinoburitsa mamorekuru madiki akadai seADP, ATP, serotonin, uye calcium, ayo anoita basa guru mukuwedzera kweropa, zvichikwezva maplatelet akawanda kunzvimbo yakakuvara, uye kuwedzera kushanda kwemaplatelet.
Semuenzaniso, ADP inosungana neP2Y12 receptor iri pamusoro peplatelet, zvichikonzera shanduko muchimiro cheplatelet, zvichiwedzera kubatana kwayo nefibrinogen, uye zvinosimbisa kubatana pakati peplatelet, zvichikonzera kuungana kwakasimba. Calcium inoita basa rakakosha mumatanho akasiyana-siyana ekugwamba, ichibatsira kuumba enzymatic complexes pamusoro peplatelet.
3. Kuonda uye Kuumbwa kweFibrin
Pamusoro pekuumba platelet plug nekuburitsa ma mediator, maplatelet anokurudzirawo kuumbwa kwefibrin, puroteni inosimbisa uye inodzikamisa platelet plug. Maplatelet anoshandiswa anopa nzvimbo inobatsira kudyidzana kwezvinhu zvinobatanidza ma "coagulation factors" munzira dzemukati nedzekunze, zvichizopedzisira zvaita kuti fibrinogen inonyungudika ive insoluble fibrin. Fibrin inobva yaumba network inobata masero matsvuku eropa nemamwe masero muropa, zvichiita kuti ropa rigare rakagwinya.
4. Kuporeswa Kwemaronda
Kuwedzera pabasa rawo mukudzikira kweropa, maplatelet anobatsirawo mukurapa maronda. Zvinhu zvinokura zvinoburitswa nemaplatelet, zvakaita sePDGF, vascular endothelial growth factor (VEGF), uye transforming growth factor-beta (TGF-β), zvinokurudzira kuwanda nekufamba kwemasero kunzvimbo yeronda, kusanganisira fibroblasts, endothelial cells, uye epithelial cells. Maitiro aya anobatsira mukuumbwa kwenyama itsva netsinga dzeropa (angiogenesis), iyo inokosha kuti ronda ripore zvakanaka.
Matambudziko ePlatelet
Kusashanda zvakanaka kana kusashanda zvakanaka kwehuwandu hwemaplatelet mumuviri kunogona kukonzera matambudziko akasiyana-siyana ehutano:
– Thrombocytopenia: Kuwanda kwemaplatelet mumuviri kunogona kukonzera kubuda ropa rakawanda izvo zvinonetsa kumisa. Dambudziko iri rinogona kukonzerwa nezvinhu zvakasiyana-siyana, zvinosanganisira zvirwere zve autoimmune, hutachiona, kana migumisiro yemishonga.
– Thrombocytosis: Kuwanda kwemaplatelet kunogona kuwedzera njodzi yekuumbwa kweropa rakagwamba, izvo zvinogona kukonzera sitiroko kana kurwara nemoyo. Zvikonzero zvinogona kusanganisira zvirwere zve myeloproliferative, maitiro ehutachiona kana kuzvimba, kana chikamu chechirwere chisingaperi.
– Kusashanda zvakanaka kwemaplatelet: Maplatelet asingashande zvakanaka, kunyangwe huwandu hwawo hwakafanana, anogonawo kukonzera matambudziko ekubuda ropa, senge mune mamwe matambudziko emajini kana nekuda kwemishonga yakati wandei.
Mhedziso
Maplatelet anoita basa rakakosha muhurongwa hweropa neropa rinobuda ropa. Ndiwo akakosha pakudzivirira kwemuviri kubva pakubuda ropa uye ane mamwe mabasa mukuporesa maronda. Kunzwisisa maplatelet, mune mamiriro ezvinhu akajairwa uye ezvirwere, kwakakosha pakudzivirira nekurapa zvirwere zvakasiyana-siyana zveropa. Tsvagiridzo iri kuramba ichiongorora zvinhu zvakasiyana-siyana zvemaplatelet, kusanganisira kugona kwawo mukurapa uye kupindira mukiriniki.
