Basa rePlatelet muKuvhara Ropa
Kugwamba kweropa, kana kuti kuvharika kweropa, inzira inokosha yehupenyu inodzivirira kubuda ropa rakawanda mushure mekukuvara kwenyama. Pakati pezvinhu zvakasiyana-siyana zvemasero nemamorekuru zvinobatanidzwa mubasa iri rinokosha pane maplatelet, anozivikanwawo semathrombocytes. Maplatelet zvidimbu zvidiki zvemasero, zvakaita sedhisiki zvinobva kumamegakaryocytes ari mumongo wemapfupa. Pasinei nehukuru hwazvo hushoma, zvinhu izvi zvemasero zvinoita basa guru mu hemostasis—nzira inomisa kubuda ropa—uye inokosha pakugadzirisa maronda uye hutano hwemwoyo. Chinyorwa chino chinotarisa kushanda kwakaoma kwemaplatelet mumagwamba eropa, zvichitsanangura rwendo rwawo kubva pakutenderera kweropa kusvika pakuumbwa kwegwamba rakagadzikana.
Kuumbwa kwePlatelet uye Kutenderera Kwehupenyu
Rwendo rweplatelet runotangira mumongo wemapfupa, uko megakaryocytes dzinopinda muitiro wakaoma unonzi endomitosis, zvichikonzera kugadzirwa kwezviuru zveplatelet pa megakaryocyte imwe neimwe. Platelet yega yega ine dhayamita inosvika 2-3 micrometers uye inotenderera muropa kwemazuva angangoita 7-10 isati yabviswa nepleen nechiropa.
Maplatelet ane maorganelles akawanda nemagranules, azere nezvinhu zvinogwamba ropa, maenzymes, uye zvinhu zvinokura. Mamembrane avo akashongedzwa nemareceptor akasiyana-siyana anovabvumira kushanda pamwe nemamwe masero nezvimwe zvikamu muropa. Izvi zvinoita kuti maplatelet akwanise kupindura zvinobudirira uye zvine hungwaru pakukuvara kwetsinga dzeropa.
Basa remaplatelet muHemostasis
Kupera kweropa (hemostasis) inzira ine matanho akawanda inogona kukamurwa kuva: kupora kweropa (primary hemostasis) uye kupora kweropa (secondary hemostasis) (kusimbisa platelet plug ne fibrin mesh). Maplatelet anobatanidzwa zvakanyanya muzvikamu zvese izvi.
1. Kubuda Kweropa Muropa Kwekutanga: Kuumbwa kwePlatelet Plug
Kana tsinga yeropa ikakuvara, masero e endothelial ari mutsinga anoburitsa mamorekuru ekuratidza zviratidzo uye anoburitsa subendothelial collagen uye tissue factor. Kuonekwa uku kunoshanda sechiratidzo chekushungurudzika chinokwezva maplatelet anotenderera kunzvimbo yakakuvara. Maitiro makuru e hemostatic anosanganisira maplatelet anosanganisira:
– Kunamatira: Danho rekutanga rinosanganisira kunamira kwemaplatelet kune subendothelial matrix yakavhurika, kunyanya collagen. Kunamatira uku kunokonzerwa nevon Willebrand factor (vWF), iyo inoshanda sebhiriji pakati peplatelet surface receptor glycoprotein Ib-IX-V complex necollagen.
– Kushanda: Kana maplatelet akabatana, anotanga kushanda. Kushanda uku kunokonzera shanduko muchimiro chemaplatelet kubva pakuvaka kwakaita sediski kuenda kuchimiro chine minzwa, zvichiwedzera nzvimbo yawo yepamusoro. Maplatelet anobuda anoburitsa zviri mukati memagranules awo, anosanganisira ADP, serotonin, calcium, uye thromboxane A2. Zvinhu izvi zvinowedzera kushanda kwemaplatelet akapoteredza uye zvinounganidza mamwe maplatelet panzvimbo yacho.
– Kuungana: Maplatelet anoshandiswa anounza glycoprotein IIb/IIIa receptor pamusoro pawo, iyo inosunga fibrinogen ne vWF, zvichiita kuti pave nemaplatelet bridges uye zvichikonzera kuungana kwemaplatelet. Kuungana uku kunoguma nekuumbwa kwepulagi ye hemostatic primary, ichivhara kukuvara kwenguva pfupi.
2. Kupera Kweropa Kwechipiri: Kusimbiswa kwePlatelet Plug
Kunyange zvazvo chivharo chekutanga chehemostatic chichigadzirwa nekukurumidza, hachina kusimba uye chinoda kusimbiswa kuti chive nechokwadi chekuti hemostasis inogara kwenguva refu. Secondary hemostasis inosanganisira coagulation cascade, runyorwa rwema enzyme reactions anoguma nekuumbwa kwe thrombin. Thrombin ienzyme ine simba inoshandura soluble fibrinogen kuita insoluble fibrin strings, iyo inosvetukira nepakati peplatelet plug, ichiisimbisa. Iyi fibrin mesh inodzikamisa clot uye inoita kuti irambe yakasimba pakurwisa simba rekuyerera kweropa.
Basa reMaplatelet Rinopfuura Kupera Kweropa
Kunze kwebasa ravo guru mu hemostasis, maplatelet anobatanidzwa mune zvakasiyana-siyana zvemuviri uye zvezvirwere:
– Kuporeswa Kwemaronda: Maplatelet anoburitsa zvinhu zvinokura zvakaita seplatelet-derived growth factor (PDGF) uye transforming growth factor-beta (TGF-β), izvo zvakakosha pakugadzirisa nekuvandudza matishu.
– Kuzvimba: Maplatelet anoshandiswa anoburitsa ma cytokines nema chemokines anokonzera kuzvimba, zvichibatsirawo pakuita kwekuzvimba. Anoshandawo nema leukocytes (masero machena eropa), zvichiita kuti afambe achienda kunzvimbo dzine kuzvimba kana kukuvara.
– Kupindura Kwemuviri Wemuviri: Maplatelet anobatanidzwa mukudzivirira muviri kubva muzvirwere zvemuviri kuburikidza nekuziva utachiona zvakananga kuburikidza nema toll-like receptors (TLRs) nemamwe ma pattern recognition receptors. Anogona kutobata nekupa ma antigen kumasero emuviri wemuviri, nokudaro achibatanidza kudzivirira muviri kwemuviri kwemuviri uye kunochinjika.
– Kusawirirana kweThrombosis neHemostasis: Kunyange zvazvo maplatelet achikosha pakudzivirira kubuda ropa, kusashanda zvakanaka kwawo kunogona kutungamira kumamiriro ezvinhu echirwere. Kushanda zvakanyanya kwemaplatelet uye kuungana kunogona kukonzera thrombosis, zvichikonzera mamiriro akadai se myocardial infarction, sitiroko, kana deep vein thrombosis. Kusiyana neizvi, kusashanda zvakanaka kwemaplatelet kana kugadzirwa kwawo kunoguma nematambudziko ekubuda ropa akadai se thrombocytopenia.
mhedziso
Muchidimbu, maplatelet akakosha zvikuru mukuita kwekugwamba kweropa. Kubva pakuumbwa kwawo mumongo wemapfupa kusvika pabasa rawo guru mukudzikira kweropa kwekutanga nekwechipiri, ndiwo anochengetedza tsinga dzeropa. Anoshanda nekukurumidza uye zvinobudirira kana tsinga dzeropa dzakuvara, achidzivirira kubuda ropa uye achitanga nzira dzekugadzirisa. Uyezve, mabasa awo anopfuura kudzikira kweropa, achikanganisa kupora kwemaronda, kuzvimba, dziviriro yemuviri, uye mamiriro akasiyana-siyana ezvirwere.
Kunzwisisa mabasa akaomarara uye ane mativi akawanda emaplatelet hakungoratidzi chete maitiro ekutanga ehupenyu asiwo kunovhura nzira itsva dzekurapa. Mishonga yakanangwa inogona kugadzirisa mashandiro emaplatelet inogona kupa nzira itsva dzekurapa matambudziko ekugwamba kweropa, zvirwere zvemwoyo, uye zvirwere zvekuzvimba. Sezvo tsvakiridzo ichiramba ichiburitsa pachena kuomarara kwebiology yemaplatelet, masero madiki aya asi ane simba pasina mubvunzo acharamba ari pamberi musainzi yekurapa.
