Umsebenzi kanye nesakhiwo zegazi

Ama-platelet I, okuyinto zenzelwe ukubhekana okungazelelwe ukopha, ngokuthi platelet. Zinqwabelanisa ezindaweni kokulimaza iyiphi imithambo yegazi kanye clog nabo plug ekhethekile.

ukubukeka amapuleti

isakhiwo platelet kungenziwa akubonakali ngesibonakhulu. Babukeka njengezihlahla a disc, ububanzi okuyinto kuhluka 2 kuya 5 microns. Umthamo ngamunye wabo emhlabeni 5-10 microns ^3.

Uma sibheka ukwakheka kwazo bayo, izinhlayiya zegazi kukhona ukuxuba eziyinkimbinkimbi. Yena emelelwa microtubule uhlelo, ulwelwesi, organelles futhi microfilaments. ubuchwepheshe besimanje ukuvumela ukusika ipuleti ukusabalala-eagled zibe izingxenye ezimbili kanye ukwaba ke eziningi esishintshashintshayo. Lokho bakwazi kanjani ukukhomba izici isakhiwo platelet. ipuleti ngasinye siqukethe izingqimba eziningana: zone neuropathy, i-sol-gel, organelles intracellular. Bobabili babe umsebenzi wabo siqu futhi injongo.

olwelwesini

Le ndawo neuropathy yakhiwa ulwelwesi emithathu ungqimba. isakhiwo Platelet yokuthi Ohlangothini olungaphandle thereof is ungqimba equkethe izici plasmatic obangela ekunqandeni ukopha, receptor ethize kanye enzyme. Uhlonze lwalo lingaphansi kuka-50 NM. Receptor lokhu ungqimba platelet unesibopho ukusebenza kwawo la mangqamuzana futhi umthamo kwabo adhesion (ukunamathela subendothelium) kanye aggregation (amathuba oxhumene).

Futhi, ulwelwesi phospholipid yakhiwa isici esikhethekile 3 noma okuthiwa i-matrix. Le ngxenye unesibopho kumiswa asebenzayo coagulation izakhiwo kanye plasma izici obhekene igazi ekunqandeni.

Ngaphezu kwalokho, kuyinto arachidonic acid. Kuyinto ebalulekile phospholipase A. Ukuthi akha acid adingekayo synthesis prostaglandins. Nazo ngokufanayo, zenzelwe kumiswa thromboxane A _2, esidingeka anamandla platelet wokuhlanganisa.

glycoproteins

isakhiwo platelet akugcini khona uma kubanda ulwelwesi olungaphandle. lipid wayo bilayer kukhona glycoproteins. Ziklanyelwe ukuba ngibophe abanhliziyo-platelet.

Ngakho, glycoprotein mina kuyinto yokwamukela obhekene okunamathiselwe ku subendothelial collagen lezi egazi. Inikeza adhesion zegazi, bawendlala nokuxhumanisa kubo nomunye amaprotheni - fibronectin.

Glycoprotein II yakhelwe zonke izinhlobo platelet wokuhlanganisa. Inikeza yokubopha fibrinogen egazini kulezi cells. Kuyinto kule nqubo iyaqhubeka wokuhlanganisa zingancishiswa nokwehlisa (sokuhoxisa) we kweqembu.

Kodwa glycoprotein V ukuze nokugcina kwakwakhe platelet. Ubizwa hydrolyzed ngu thrombin.

Uma kusendlalelo wathi incipha platelet ulwelwesi glycoproteins okuqukethwe okuhlukile, iba imbangela ukopha anda.

I sol-gel

Kanye yesibili ungqimba platelet Kutholwe ngezansi ulwelwesi, kuyinto indandatho microtubule. platelet isakhiwo egazini womuntu wukuthi lezi amashubhu bangabezwe apharathasi contractile. Ngakho, lapho ukukhuthazwa lezi amapuleti ushukumisela indandatho onomfutho futhi elimbudumbudu kuseli isikhungo. Ngenxa yalokho, basuke onomfutho. Konke lokhu kubangela uketshezi lokuqukethwe zabo ngaphandle. Lena sibonga kungenzeka indlela ekhethekile tubules evulekile. Le nqubo ibizwa ngokuthi "yinye granules."

Nge zokunciphisa microtubule indandatho futhi kuba nokwenzeka yakha pseudopods ukuthi uthanda ukwanda wokuhlanganisa ikhono kuphela.

organelles intracellular

Isendlalelo lwesithathu yakhiwa elimbudumbudu glycogen, mitochondria, α-granules, emizimbeni obukhulu. Lokhu okuthiwa organelles zone.

emizimbeni Okuwugqinsi aqukethe ATP, Adp, serotonin, i-calcium, i-adrenalin kanye noradrenaline. Bonke bangabangasokile ezidingekayo ukuze bakwazi ukusebenza platelet. Isakhiwo nokusebenza kwalezi zici amaseli ukunikeza adhesion kanye isilonda sisheshe siphole. Ngakho, Adp akhicitwe nakuchubeka ukunamathela platelet ezindongeni semithambo, kubuye kube obhekene yokuthi plate wathi kusukela kwegazi waqhubeka enezela labo bolimi kakade. Calcium ulawula ukushuba adhesion. Serotonin kuveza ukukhulula platelet granule. Liqinisekisa ngesikhathi sekhefu ukuvaleka semithambo we Isikhala sayo esingaphakathi.

Alpha granules, organelles yatholakala endaweni, laba kanjani nesandla ekwakhekeni platelet lokubolekwa. Ziyakwazi obangela ukukhuthazwa bushelelezi kwemisipha ukukhula, yokutakula isitsha odongeni imisipha abushelelezi.

Inqubo amaseli ukwakha

Ukubhekana lokho, yini isakhiwo platelet womuntu, kudingeka uqonde basuka kuphi futhi kwakhiwa kanjani. Inqubo ukuvela kwabo bagxila umnkantsha. It ihlukaniswe yaba izigaba eziningana. Ekuqaleni kwakhiwa megakaryocyte koloni ukwakha iyunithi. Ukuze izigaba eziningana, yena uguqulwe megakaryoblasts, promegakaryocyte futhi ekugcineni ku platelet.

Nsuku zonke, umzimba womuntu ukhiqiza oda 66.000 amaseli ngayinye 1 l kwegazi. Esikhathini omdala serum womuntu kumele tisukele 150 kuya 375, ingane 150 kuya ku-250 x 10 ⁹ / l-platelet. Ngakho u-70% wabo afundwa emhlabeni umzimba, kuyilapho ama-30% zanqwabelana ubende. Uma kudingekile, umzimba kwehlisa futhi ukukhishwa platelet.

imisebenzi eyisisekelo

Ukuze uzwisise ukuthi umzimba kudingeka zegazi, nokuqonda okuncane mayelana nokuthi ikuphi ethile yomuntu platelet isakhiwo. Ziklanyelwe ngokuyinhloko ukuze kwakhiwe amashubhu okuyinto kumele ivale isitsha lilimele. Ngaphezu kwalokho, izinhlayiya zegazi unikeze ebusweni ukuze ukusheshisa ukusabela ekunqandeni plasma.

Ngaphezu kwalokho, kwatholakala ukuthi ziyadingeka ukuze ukuvuselelwa nokwelashwa kwezicubu ahlukahlukene obonakele. Ama-platelet I ukukhiqiza nezici ukukhula, okuhloswe ukuze sikhuthaze ukuthuthukiswa nokuhlukana kwamangqamuzana lilimele.

Kuyaphawuleka ukuthi bangakwazi ngokushesha futhi unomphela ukuthuthela isimo esisha. Umfutho kusebenze zabo kungaba yisiphi emvelweni, kuhlanganise nokucindezeleka elula lokukhanda.

ikakhulukazi zegazi

Ukuhlala la egazi eside. Ngokwesilinganiso, isikhathi khona kwazo kuvela izinsuku 6.9 kuya 9.9. Ngemva kokuphela kwalesi sikhathi bachotshozwe. Empeleni, le nqubo ithatha indawo umnkantsha, kodwa futhi ngezinga elincane, kuba ubende kanye esibindini.

Ochwepheshe ukukhomba izinhlobo ezinhlanu ezahlukene zegazi: abasha, avuthiwe, ubudala, kanye namafomu esiwohlozayo yokucasuka. Ngokuvamile, umzimba kumele kube ngaphezulu kuka-90% amaseli ovuthiwe. Kuphela kulesi simo isakhiwo platelet muhle, futhi bazokwazi ukwenza yonke imisebenzi yawo ngokugcwele.

Kubalulekile ukuqaphela ukuthi ukwehla lokuhlushwa lezi egazi siyimbangela ukopha ukuthi kunzima ukuyeka. Ukwenyuka isibalo sabo sincane imbangela thrombosis - ukubukeka amahlule. Abakwazi clog imithambo yegazi izitho ezihlukahlukene zomzimba, noma kutsetselelwe kubo.

Ezimweni eziningi, le ezihlukahlukene isakhiwo izinkinga platelet akashintshi. Zonke izifo ahlobene nezinguquko emakamu abo ohlelweni igazi. Ukwehla inombolo yabo ibizwa thrombocytopenia. Uma emakamu luyanda, libizwa thrombocytosis. Uma wephula umsebenzi la mangqamuzana uxilongwe thrombasthenia.