I-enzyme ebangela ukugwedla kwegazi, kuthiwa yini?

Kuhle uma inkinga enjalo, njengokunqunywe noma ukuphazamiseka, iphilisa ngokushesha futhi ngaphandle kwezinkinga. Asinamathisi ukubaluleka kokuthi amandla, izinto nezinhlelo eziningi zihileleka ekuqinisekiseni ubuqotho bomzimba wethu.

Iyini isimiso segazi coagulation?

Ezesayensi yezokwelapha, isimiso segazi esihlanganisayo sebizwa ngokuthi "homeostasis." Lena inqubo ehlinzeka ngesimo segazi esiyinkimbinkimbi, futhi ivimbela ukulahlekelwa kwenani elikhulu. Igazi kubantu liwumthombo wokuphila, ngoba ngosizo lwazo zonke izinto eziwusizo zingena kumaseli. Akugcini nje ukondla umzimba, kodwa futhi uyakuvikela. Lokhu ketshezi emzimbeni akusiyo kakhulu, ngakho konke ukugoba noma ukusika okuphula ukwethembeka kwemikhumbi, kungaqeda kabi. Kodwa isimiso se-coagulant, i-enzyme yaso ngokuqondile, okwenza ukuba igazi lixhumane luza usizo . Labizwa ngokuvumelana nezinhlayiya zalesi sakhiwa ngamaplatelet.

Lolu hlelo luhlukile, njengoba lusendaweni egazini kuyo yonke imithwalo yegazi. Lapho nje umkhumbi uphazamiseka, izinto ezihlukahlukene kanye nezinqubo ezifaka ngokushesha umsebenzi ovala umgodi emkhunjini. Lolu hlelo alugcini ngegazi kuphela, kodwa liphinde livimbe ngokusebenzisa izinto ezihlukile. Ngokuvamile, zonke izinqubo zilinganiselwe, ngenxa yokuthi umsebenzi wegazi usebenza ngokugcwele ngisho nezitsha ezilimele.

I-Anticoagulation yegazi

Umsebenzi walesi simiso ukulawula ukuvalwa kwegazi. Phela, uma le nqubo ingalawulwa, izoholela ekuphukeni komsebenzi obalulekile wokuzivikela. Uhlelo lwe-anticoagulant luhlose ukuvimbela ukwakheka kwe-thrombi kuyo yonke imikhumbi, ukuze ukuxhuma kusebenze kuphela ezindaweni ezilimaziwe. Ngaphezu kwalokho, ama-anticoagulants ahlale egcina isimo segazi esiphezulu segazi, ephikisana nokuthambekela kwe-viscosity nokuqina kwalolu shizi.

Ezingeni lokuphila, i-heparin, i-antithrombin, amaprotheni, i-inhibitors yezici ezihlukahlukene (i-anticoagulants yalesi simiso) ivimbela ukubunjwa kwe-fibrin, ivimbela ukuhlukunyezwa kwama-erythrocyte, amaplatelets futhi igweme ukukhiqizwa kwe-thromboplastin ngomzimba. Kodwa nokho, yiliphi igama le-enzyme yokuqeda igazi, futhi yini umphumela walo?

Kungani sidinga ukuchithwa kwama-blood clots ohlelweni lwe-coagulation?

Ingxenye yesithathu yenqubo yonke yesilinganiso se-system coagulation system iyisistimu ye-fibrinolytic. Umsebenzi wayo ukuchitha i-thrombi ekhona. Le nqubo iyadingeka lapho umsebenzi oyinhloko usuqedile, futhi ubuyiselwa kwesitsha bubuyiselwe. I-Hemostasis iphela ngokuphepha uma lezi zakhi ezintathu ze-blood coagulation system zisebenza ngokulinganisela. Uma kungenjalo, kukhona ukwephulwa kule nqubo - kungase kube nokweqa noma ukwakheka kwe-thrombus ngokweqile. Lokhu "ukukhathazeka" emsebenzini kukhonjelwa ezifweni zesibindi, amaphaphu, ama-neoplasms, i-IHD, i-rheumatism nezinye izifo.

Ukuvalwa kwegazi kuqala kanjani?

Ukuvala inguquko, ukuguqulwa kwegazi elimanzi libe yi-clot-like clot. Ngenxa yalokhu msebenzi, umzimba uzisindisa ekulahlekelweni kwegazi. Uma umkhumbi omncane ubonakalisiwe, ama-clot forms (uma i-enzyme eyenza i-coagulability iqale ukusebenza), efana nokuyeka, okusiza ukumisa ukuphuma kwegazi.

Ukuqoqwa kwegazi kwenzeka ngenxa yesistimu ekhethekile, eqondwa njengama-inhibitors we-coagulation, ukusebenzisa izici. I-enzyme, ebangela ukugwedla kwegazi, ikhiwa njalo. Ama-inhibitors asebenza ngemodi eqhubekayo ngezigaba:

• Isigaba 1. I-Heparin ne-antiprothrombinase iqala ukwenza.
• Isigaba 2. I-Thrombin inhibitors (i-fibrinogen, i-fibrin, i-prethrombin I no-II, imikhiqizo ye-hydrolytic thrombin) ingena emsebenzini.

Ngezifo eziningi emzimbeni, ama-inhibitors engeziwe akhiwa. Kwabaningi, kusalokhu kuyimfihlakalo okuyinto i-enzyme eyenza i-blood coagulability. Emva kwakho konke, izakhi eziningi kanye nezinto ezibandakanya kule nqubo. Kodwa bonke benza imisebenzi yabo eqinile, uma le enzyme ilahlekelwa ukuqina kwayo kwegazi, ngisho nokulimala okuncane emkhunjini kuyoholela ekufeni kwegazi.

I-enzyme eyabangela ukugoqa igazi

Sithole ukuthi yini esiyidingayo isistimu eguqukayo, manje sizobe sibheke ngokucophelela izindlela zayo zomzimba. Iyini igama le-enzyme elibangela ukugoqa igazi? Into esemqoka kule nqubo ixhuma emndenini we-trypsin. Esikhathini sokuphendula kwamakhemikhali, sisebenza kwi-fibrinogen futhi siyifake kuyi-fibrin. I-enzyme eyenza ukugaya igazi, igxilile kakhulu i-fibrinolysis ne-thrombosis, ithoni ye-vascular. Ukwakhiwa kwe-enzyme kwenzeka ngezinqubo zokuvuvukala.

Kusukela ku-prothrombin kubonakala sengathi i-thrombin esigabeni sokugcina se-coagulation. I-Thrombin ikhuthaza ukuqaliswa kwezimpawu ze-V, VIII, XIII. Inamakhemikhali e-hormonal, aboniswa ngokuxhumana nama-platelet namaseli wokugcina. Ngesikhathi uxhumano ne-thrombomodulin, le-enzyme iphela ukuphinda igazi.

Izigaba zeHemostasis: Iyiphi indima i-enzyme yokuvala igazi edlala

Isici se-hemostasis ukuvalwa kwesitsha esonakalisiwe. I-filaments ye-fibrin ikhuthaza ukwakheka kwe-thrombus, ngemva kwalokho igazi lithola izindawo ze-astringent. Iyini igama le-enzyme elibangela ukugoqa igazi? Igama lifana negama elithi "thrombus" - thrombin. Uhlale ekulungele ukusebenza, futhi uma ukwephulwa kuqala ukwenza isenzo esiqinile. I-Hemostasis ihlukaniswe ngezigaba eziningana:

1. Isigaba se-prothrombinase okwenzekayo. Kulesi sigaba, ama-tissue ne-enzyme egazi akhiwa, inqubo yokwakheka kwazo ihamba ngamanani ahlukene. Ukwakhiwa kwegazi prothrombinase ngokuqondile kuxhomeke kumzimba we-prothrombinase (i-enzyme yezicubu isebenza izici zokwakhiwa kwe-enzyme yegazi). Kulesi sigaba esifanayo, kunesimo sangaphandle nesingaphakathi kwe-hemocoagulation.
2. Isigaba sesizukulwane se-thrombin. Kulesi sigaba, sithola impendulo yombuzo wokuthi iyiphi i-enzyme eyenza igazi liguqulwe. I-prothrombin ihlukaniswa zibe yizingxenye futhi kutholakala into esebenzayo e-thrombin, evuselela izigaba ezilandelayo futhi iqaphele umfundisi.
3. Isigaba sokuqala kwe-fibrin. I-Thrombin (i-enzyme eyabangela ukugoqa kwegazi) ithinta i-fibrinogen, ama-amino acids aqanjiwe.
4. Lesi sigaba sikhethekile ekutheni i-polymerization ye-fibrin nokwakhiwa kwe-clot kwenzeka.
5. I-Fibrinolysis. Kulesi sigaba, i-hemocoagulation igcwaliswe.

I-coagulation yangaphandle

Le ndlela inzima kakhulu futhi isinyathelo ngesinyathelo. Okokuqala, izindawo ezilimele zihlangana negazi, kusebenze i-III factor of thromboplastin. Emva kwalokho, uguqula iVII (proconvertin) kuVII-A (convertin). Ngenxa yalokhu kusabela, inhlanganisela yeCa ++ + III + VIIIa, isebenze i-X-factor, ivela, futhi iguqula ibe yi-Xa. Njengomphumela wazo zonke izinqubo, kunesinye isakhiwo esibonakala sengathi sinayo yonke imisebenzi ye-tishu prothrombinase. Ukuba khona kwe-Va kubonisa ukuba khona kwe-thrombin kusebenze i-V-factor. Kuyinto i-prothrombinase yezicubu ezenza i-prothrombin ibe yinkimbinkimbi. Le enzyme ibangele ukuxosha igazi, kusebenze izici V no VIII, ezidingekayo uma i-blood protrombinase ivela.

"I-Internal" yokuvala igazi

Kanye ne-coagulation yangaphakathi, yangaphakathi ibangelwa. Uma uxhumane nengxenye engalingani yomkhumbi, isici se-XII (XII-XIIa) senziwa. Ngesikhathi esifanayo, kuhlanganiswa isikhali se-hemostatic. Isici se-XII esisebenzayo senza i-XI, kamuva i-XIIa + Ca ++ + XIa + III ibonakala, echaphazela i-IX futhi yenza isakhiwo esiyinkimbinkimbi. Uvuselela i-X, bese i-Xa + Va + Ca ++ + III ivela, okuyi-prothrombinase yegazi. Lapha, enye i-enzyme idala ukugaya igazi. Ukuhlukaniswa kube "kwangaphandle" futhi "kwangaphakathi" kunemibandela futhi kusetshenziselwa imibuthano yesayensi kalula, ngoba lezi zinqubo zihlobene kakhulu.

Indima yezici zokuvala izinkinga kule nqubo

Sitsho kakade ukuthi inqubo yokweqa igazi ayikwenzi ngaphandle kwemithi ethile ebizwa ngokuthi izici. Lezi zinto ziyi-proteins e-plasma, eyaziwa ngezesayensi yezokwelapha.

• I-Fibrin ne-fibrinogen. I-Fibrinogen ifakwe yisenzo sokuthinta i-thrombin.
• I-Thrombin ne-prothrombin. I-prothrombin i-glycoprotein, kuwanele egazini ukuguqula i-fibrinogen ibe yi-fibrin. I-Thrombin iyi-enzyme eyenza i-coagulability yegazi, imifula yayo kuphela ebonakala kuyo.
• Thromboplastin. Unesakhiwo se-phospholipid, ekuqaleni asisebenzi. Uyingxenye eyinhloko yesigaba sokuqala.
• I- Ca ++ ye- calcium ionized . Uthatha ingxenye ekhuthele ekwenzeni i-homeostasis.
• I-Proaccelerin ne-acceclerin (AC-globulin). Kubandakanyeke ngezigaba ezimbili ze-coagulation. Izinqubo eziningi ze-enzyme ziyashesha.
• I-Proconvertin futhi iguquke. Kuyiprotheni yeqhezu le-beta-globulin. Ivuselela i-protobinase ye-tissue.
• I-Antigemophilic globulin A (AGG-A). Ilungu le-prothrombinase yegazi. Uma engekho le protheyini, i-hemophilia iqala. Inani elincane egazini, kodwa kubaluleke kakhulu kubantu.
• I-Antigemophilic globulin B (AGH-B, i-Christmas factor). I-Catalyst ne-X-factor activator.
• I-Koller factor, Steward-Prawer factor. Abahlanganyeli be-prothrombinase.
• Isici se-Rosenthal, isandulela se-plasma ye-thromboplastin (PPT). Isheshisa inqubo yesenzakalo se-prothrombinase.
• I-factor factor, uHagann factor. Ziyizimbangela zendlela yokuvala i-clotting. Kubandakanyeke ekusebenziseni kwezinye izici.
• Lucky-Lorand fibrinstabilizer. Kudingekile ukuthola i-fibrin engasebenzi.

Zonke lezi zici zidingekile ekunciphiseni kahle, lapho le nqubo ivela masinyane futhi ihamba ngendlela efanele, ngaphandle kokuhola umzimba womuntu ekulahlekeni kwegazi ngokweqile.

Indlela yokubunjwa kwe-thrombus

Ukubuyiselwa kwezikebhe ezimele kungenzeki ngandlela-thile, kuhilela izinto eziningi ezenza ngendlela ehlelekile, ukwenza imisebenzi yazo. Okuyinhloko yale nqubo ukuthi i-coagulation engenakuphikiswa yamaprotheni namaseli egazi okwenzekayo. I-thrombus ihlanganiswe nodonga lwama-vascular, uma i-thrombus ijoyine isitsha, khona-ke inqola yayo eqhubekayo ayikwenzeka.

Lapho umkhumbi ubonakalisiwe, izinto ezisiza ukuvimbela izinqubo ze-coagulation zikhishwa kuwo. I-thrombocyte ishintsha futhi iwa, okwenza kube nokugeleza egazini lama-procoagulants: i-thromboplastin ne-thrombin, i-enzyme edala igazi. Ngaphansi kwesenzo saso, i-fibrinogen iba i-fibrin, enesimo somshini futhi isisekelo se-thrombus. Le mesh isikhathi esithile iba mkhulu. Kulesi sigaba, ukubunjwa kwe-thrombi kuphelile, igazi limisiwe.

Ukuvala isikhathi njengesibonakaliso somsebenzi we-enzyme

Isikhathi esivela ngesikhathi sokulimala ekumeni kokuphuma kwegazi kuthatha imizuzu emibili kuya kwemibili. I-enzyme idala ukugwedla kwegazi imizuzu engu-10. Lesi sikhathi sizohambisana nalokho okwenzekayo lapho kungekho ukwephulwa kwezinhlelo eziyinhloko ezihilelekile kule nqubo. Kodwa zikhona izifo lapho inqubo yokugwedla ihamba khona noma ayikwazi neze. Izifo ezinobungozi ezinjalo yi-hemophilia, isifo sikashukela kanye nezinye.

Ukubandakanyeka kwesimiso sezinzwa kule nqubo

Uma kwenzeka umonakalo, umzimba uthumela isignali yobuhlungu ebuchosheni. Izinqubo zokuguqula izinhlungu. Lolu hlobo lokuvuselela lusiza ukusheshisa ukuvala. Ezimweni ezibuhlungu, ukwesaba kuyanezelwa, okuqhubeka kwandisa ukusebenzisana nesenzo sokuthinta. Uma ubuhlungu busebenza isikhathi esifushane, i-enzyme ye-enzyme i-thrombin yegazi isebenza ukuze ukubuyela esimweni esivamile kwenzeke ngokushesha kakhulu, kunomshini wokucabanga kuphela ohilelekile. Ubuhlungu obude buhlanganisa indlela yokuhlekisa nokugaya igazi, ukuphulukiswa kwezicubu kwenzeka kancane kakhulu.

Uma kuvezwe izinzwa zomzwelo noma ngemuva kwejoza le-adrenaline, i-coagulability iyanda. Ngesikhathi isenzo sezinzwa ze-parasympathetic sinciphisa lezi zinqubo. Iminyango isebenza ndawonye futhi isekelelana. Ngemva kokuyeka igazi, umsebenzi wesistimu ye-parasympathetic ukwandisa, okwenza umsebenzi we-anticoagulation.

Uhlelo lwe-endocrine lokusiza i-hemostasis

Zonke izitho eziyingxenye yesimiso se- endocrine zibaluleke kakhulu emisebenzini yazo. I-hormone inomthelela omkhulu emasimini omzimba. Ukusheshisa inqubo yokweqa igazi ama-hormone anjalo njenge-ACTH, STG, i-adrenaline, i-cortisone, i-testosterone, i-progesterone. Umphumela wokuphuza i-hemostasis: i- hormone ye -thyroid-stimulating , i-thyroxine ne-estrogens. Uma kunokuphazanyiswa ekusebenzeni kwamahomoni, kungase kube nezinguquko kule nqubo futhi kungase kube nezinkinga ezinkulu ezizodinga ukuxoxwa nodokotela.