I-Creatine
3K 0 02/20/2019 (ukubuyekezwa kokugcina: 02/28/2019)
I-Creatine phosphate (igama lesiNgisi - creatine phosphate, ifomula yamakhemikhali - i-C4H10N3O5P) iyinhlanganisela yamandla amakhulu eyakhiwa ngesikhathi se-phosphorylation eguqukayo ye-creatine futhi iqoqa ikakhulukazi (95%) kwezicubu zemisipha nezinzwa.
Umsebenzi wawo omkhulu ukuqinisekisa ukuzinza kokukhiqizwa kwamandla we-intracellular ngokugcina njalo izinga elidingekayo le-adenosine triphosphoric acid (ATP) nge-resynthesis.
I-biochemistry ye-creatine phosphate
Emzimbeni, umzuzwana ngamunye kunezinqubo eziningi zamakhemikhali nezomzimba ezidinga ukusetshenziswa kwamandla: ukuhlanganiswa kwezinto, ukuthuthwa kwama-molecule we-organic compounds kanye nama-microelements ezithweni zamaseli, ukusebenza kwezingcindezi zemisipha. Amandla adingekayo akhiqizwa ngesikhathi se-hydrolysis ye-ATP, i-molecule ngayinye evuselelwa izikhathi ezingaphezu kwezingu-2000 ngosuku. Akuziqoqeli ezicutshini, kanye nokusebenza okujwayelekile kwazo zonke izinhlelo zangaphakathi nezitho, ukugcwaliswa okuqhubekayo kokuhlushwa kwayo kuyadingeka.
Ngalezi zinhloso, i-creatine phosphate ihloselwe. Ikhiqizwa njalo futhi iyisisekelo esiyinhloko sokuphendula kokunciphisa i-ATP kusuka ku-ADP, ekhuthazwa yi-enzyme ekhethekile - i-creatine phosphokinase. Ngokungafani ne-adenosine triphosphoric acid, imisipha ihlala inokwanele okwanele kwayo.
Kumuntu onempilo, ivolumu ye-creatine phosphate icishe ibe ngu-1% wesisindo somzimba esiphelele.
Enkambweni yokudala i-phosphatase, ama-isoenzymes amathathu we-creatine phosphokinase abandakanyekile: izinhlobo ze-MM, MB ne-BB, ezahlukile endaweni yazo: ezimbili zokuqala zisezicutshini zamathambo nezinhliziyo, okwesithathu kusezicutshini zobuchopho.
Ukuvuselelwa kabusha kwe-ATP
Ukuvuselelwa kwe-ATP yi-creatine phosphate kushesha kakhulu futhi kusebenza kahle kakhulu emithonjeni emithathu yamandla. Imizuzwana engu-2-3 yokusebenza kwemisipha ngaphansi komthwalo omkhulu yanele, futhi i-resynthesis isivele ifinyelela ukusebenza kwayo okuphezulu. Kulokhu, amandla akhiqizwa izikhathi eziphindwe kabili kunangesikhathi se-glycolysis, i-CTA ne-phosphorylation ene-oxidative.
© makaule - stock.adobe.com
Lokhu kungenxa yokwenziwa kwabahlanganyeli abasabela endaweni eseduze ne-mitochondria nokwenza kusebenze okwengeziwe kwe-catalyst ngemikhiqizo ye-ATP cleavage. Ngakho-ke, ukwanda okubukhali kwamandla emisipha akuholeli ekwehleni kokuhlushwa kwe-adenosine triphosphoric acid. Kule nqubo, kukhona ukusetshenziswa okunamandla kwe-creatine phosphate, ngemuva kwamasekhondi angu-5-10 isivinini sayo siqala ukwehla kakhulu, futhi ngemizuzwana engama-30 yehla ize ifinyelele uhhafu wenani eliphakeme. Esikhathini esizayo, ezinye izindlela zokuguqula ama-macroenergy compounds ziyaqala ukusebenza.
Inkambo ejwayelekile yokuphendula kwe-creatine phosphate ibaluleke kakhulu kubasubathi abahlotshaniswa noshintsho olunzima kumthwalo wemisipha (ukugijima ibanga elifushane, ukukhuphula izinsimbi, izivivinyo ezahlukahlukene ezinesisindo, i-badminton, uthango nezinye izinhlobo zemidlalo eziqhumayo)
I-biochemistry yale nqubo kuphela ekwazi ukuhlinzekela ngokweqile ukusetshenziswa kwemali yamandla esigabeni sokuqala somsebenzi wemisipha, lapho ukuqina komthwalo kushintsha kakhulu futhi amandla amakhulu okuphuma kwamandla adingeka ngesikhathi esincane. Ukuqeqeshwa kule midlalo engenhla kufanele kwenziwe ngokucatshangelwa okuphoqelekile kokugcwala okwanele komzimba ngomthombo wamandla anjalo - i-creatine kanye ne "accumulator" yezibopho ezinkulu - i-creatine phosphate.
Ekuphumuleni noma ngokuncipha okukhulu kokuqina kwemisipha, ukusetshenziswa kwe-ATP kuyehla. Izinga le-resynthesis ye-oxidative lihlala ezingeni elifanayo futhi "insalela" ye-adenosine triphosphoric acid isetshenziselwa ukubuyisela izinqolobane ze-creatine phosphate.
Ukuhlanganiswa kwe-creatine ne-creatine phosphate
Izitho eziyinhloko ezikhiqiza i-creatine yizinso nesibindi. Inqubo iqala ezinso ngokukhiqizwa kwe-guanidine acetate kusuka ku-arginine ne-glycine. Ngemuva kwalokho, i-creatine ihlanganiswe esibindini kusuka kulo usawoti kanye ne-methionine. Ngokugeleza kwegazi, kuyiswa ebuchosheni nakwizicubu zemisipha, lapho kuguqulwa kube yi-creatine phosphate ngaphansi kwezimo ezifanele (ukungabikho noma umsebenzi ophansi wemisipha nenombolo eyanele yama-molecule e-ATP).
Ukubaluleka komtholampilo
Emzimbeni ophilile, ingxenye ye-creatine phosphate (cishe i-3%) ihlala iguqulwa ibe yi-creatinine njengomphumela we-non-enzymatic dephosphorylation. Leli nani alishintshiwe, futhi linqunywa ngevolumu yemisipha. Njengento engafunwanga, ikhishwa ngokukhululekile emchameni.
Ukuthola isimo sezinso, ukuhlaziywa kokukhishwa kwansuku zonke kwe-creatinine kuvumela. Ukuhlushwa okuphansi egazini kungakhombisa izinkinga zemisipha, futhi ukweqa okujwayelekile kubonisa ukuthi kungenzeka isifo sesifo.
Izinguquko ezingeni le-creatine kinase egazini zenza ukuthi kube lula ukubona izimpawu zezifo zenhliziyo nemithambo yegazi (i-myocardial infarction, umfutho wegazi ophakeme) kanye nokuba khona kwezinguquko zokugula ebuchosheni.
Nge-atrophy noma izifo zohlelo lwemisipha, i-creatine ekhiqizwayo ayingeneki ezicutshini futhi ikhishwa emchameni. Ukuhlushwa kwaso kuncike ebukhulwini besifo noma ezingeni lokulahleka kwemisipha.
Ukweqisa ngokweqile kwe-creatine kungaholela kokuqukethwe okwandisiwe kwe-creatine emchameni ngenxa yokungalandelwa kwemithetho yemiyalo yokusetshenziswa kwesengezo semidlalo.
