I-cholesterol yingxube yemvelo yezinto eziphilayo, i-polycyclic lipophilic alcohol, okuyingxenye yezingqimba zeseli cishe yazo zonke izinto eziphilayo.
I-cholesterol ayinamanzi. Iyancibilika emafutheni kanye nama-soltiv organic.
Cishe i-4/5 ye-cholesterol edingwa ngumzimba ikhishwa ngumzimba ngokwayo. Le khompiyutha ikhiqizwa ikakhulukazi amaseli wesibindi. Umzimba uthola i-1/5 elahlekile yevolumu edingekayo evela endaweni yangaphandle ngesikhathi sokudla ngezakhi zokudla.
Indima yemvelo ye-cholesterol emzimbeni
Ikhompiyutha iyatholakala emzimbeni ngezindlela ezimbili eziyinhloko. Lezi zinhlobo zamakhompiyutha zibizwa ngokuthi ama-lipoprotein aphezulu futhi aphansi.
I-cholesterol iqinisekisa ukumelana kwama-membrane we-membrane weseli ekushintsheni kwezinga lokushisa.
I-cholesterol ibandakanyeka ekuhlanganiseni kwenombolo enkulu yezithako ezisebenzayo zebhayoloji.
Umuthi ubandakanyeka kulezi zinqubo ezilandelayo:
- I-cholesterol iyisistimu ye-cell membrane fluidity stabilizer.
- Ihlanganyela ekwakhiweni kwamahomoni ocansi e-steroid.
- Ingxenye ethintekayo ekwenziweni kwama-corticosteroids.
- I-cholesterol iyisisekelo sokuhlanganiswa kwe-bile acids.
- Isakhiwo singenye yezingxenye ezibandakanyekile ekwakhiweni kwevithamini D.
- Inikeza ukuvunyelwa kwezilondolozi zeseli.
- Ivimbela umphumela wezibi ze-hemolytic kumaseli abomvu egazi.
Njengoba i-cholesterol ingasasebenzi emanzini, ekwakhiweni kwegazi ingena endaweni eyinkimbinkimbi enamaprotheni akhethekile okudlulisa, akha ama-complexes - lipoproteins.
Ukuhamba kuya kwezicubu ezithambile zento kwenziwa yi-chylomicron, i-VLDL ne-LDL.
Ukubamba iqhaza ekuphenduleni okuhlukahlukene kwe-metabolic, okutholakale i-cholesterol ethize kwenziwa emzimbeni womuntu.
Okususelwa phambili kwe-cholesterol ama-bile acid, ama-hormone e-steroid, amavithamini D nama-cholestanos.
Ezinye zezingxube zamakhemikhali eziphumayo zibandakanyekile ekuhlinzekeni ukuvikeleka komzimba kwabantu. Zivikela izifo eziningi ezibangelwa yigciwane.
Imisebenzi ye-Bile Acid
I-cholesterol emzimbeni ithambekele ku-oxidation. Iguqulwe ngamakhompiyutha ahlukahlukene e-steroid. Cishe i-70% yenani etholakalayo lamakhemikhali wamahhala wamakhemikhali enza inqubo yoku-oxidation.
Ukwakheka kwama-asidi acid kwenziwa ngamaseli wesibindi. Ukuhlushwa nokugcinwa kwe-bile acid kwenziwa ngaphakathi kwe-gallbladder. Uma kunesidingo, zithuthelwa ku-lumen wesibeletho esincane.
Lokhu kususelwa ku-cholesterol kubandakanyeka kwinqubo yokugaya.
Okubaluleke kakhulu phakathi kwe-bile acids yi-cholic acid. Ngaphezu kwaleli khompiyutha, kuvela okufana ne-deoxycholic, i-chenodeoxycholic nama-lithocholic acid. Ngokwengxenye, la ma-asidi akhona ku-bile ngendlela kasawoti.
Lezi zingxenye ziyizakhi eziphambili ze-bile. Ama-Derivatives anomthelela ekuqedweni kwama-lipids.
Ama-Hormones Derivatives we-Cholesterol
Ngaphezu kokubamba iqhaza ekwenziweni kwama-bile acid, i-cholesterol iyabandakanyeka ekwakheni inani elikhulu lama-hormone.
Ama-hormone akhiqizwa ngokubamba iqhaza kotshwala be-polycyclic lipophilic alawula imisebenzi eyisisekelo yomzimba.
Yimaphi ama-hormone avela ngesikhathi se-cholesterol metabolism?
Okususelwa kulokhu kuhlanganiswa ngamakhemikhali kufaka phakathi amakilasi ayi-5 aphambili ama-hormone e-steroid:
- ama-progestin;
- glucocorticoids;
- mineralocorticoids;
- androgens;
- ama-estrogens.
IProgesterone ehambisana ne-progestogen ilawula ukulungiswa kwesibeletho ukuze kufakwe iqanda elivundisiwe.
Ngaphezu kwalokho, i-progesterone iyadingeka enkambweni evamile yokukhulelwa. IProgesterone ehlangene namanye ama-hormone athile inesibopho sokuqinisekisa ukuthi owesilisa ugcwalisa ngokuphelele umsebenzi wakhe wokuzala. Enye yezinto ezitholakala ku-cholesterol enikeza ukugcwaliseka ngokuphelele kwemisebenzi yesilisa ngumzimba yi-testosterone.
Ama-hormone aqhamuka eqenjini lama-androgens anesibopho sokuthuthukiswa kwezimpawu zobulili zesibili emadodeni, futhi ama-estrogens abhekene nokubonakala nokukhula kwezimpawu zesibili kwabesifazane.
I-Glucocorticoids ibamba iqhaza ekwakhekeni kwe-glycogen futhi inikeze ukucindezelwa kokuvela kokuvuvukala ku-foci yokuvuvukala okwenzeka emzimbeni womuntu.
Ama-Mineralocorticoids athinta ukusebenza kwezinso. Umphumela wazo uholela ekwandeni kokugeleza kwegazi kulezi zitho nokwanda komfutho wegazi.
Isimo somuntu nesimo sakhe semizwa ikakhulukazi sincike ebukhoneni nasekuxinekeni kwama-endorphin, angama-hormone enjabul. Lezi zingxenye ezisebenzayo zemvelo zitholakala nakotshwala be-polycyclic lipophilic.
Isici samahomoni e-steroid ukukwazi ukungena kalula kulwelwesi lweseli nekhono eliphakeme lokuxhumana nama-receptors athile ku-cytoplasm noma i-nucleus yeseli elitshekile.
Ama-hormone amaSteroid ahanjiswa ngomjelo wegazi lapho enza ngawo izakhi eziyinkimbinkimbi ngamaprotheni akhethekile okuhambisa.
Vitamin D kanye ne-cholestanos
I-Polycyclic lipophilic alcohol iyisandulelo se-vithamini D. Le nto esebenza ngokusebenza kwendima idlala indima enkulu ekuqinisekiseni ukusebenza komzimba okujwayelekile. Le ngxenye ibandakanyeka ekusebenzeni kwe-calcium ne-phosphorus. Lezi zinto zidingeka ngokuyinhloko ekwakhiweni okujwayelekile kwezicubu zamathambo.
Njengomphumela wokuphendula kwe-metabolic, uvithamini D uguqulwa abe yi-calcitriol. Kamuva, leli khompiyutha kumaseli lihlangana nama-receptors athile futhi lilawula ukukhiqizwa kwezakhi zofuzo. Ngesilinganiso esanele se-Vitamin D emzimbeni, ukuthuthukiswa kwama-rickets kuyabonakala ebuntwaneni.
Okunye okususelwa kotshwala be-polycyclic lipophilic yi-cholestanos. Leli khompiyutha liqembu lama-steroid. Ukuba khona kwale nto kutholakala emithanjeni ye-adrenal, lapho iqoqana khona. Okwamanje, iqhaza lale ngxenye aliqondakali ngokuphelele.
I-cholesterol emzimbeni iguqulwa ibe isibalo esikhulu sezinto ezahlukahlukene ezisebenzayo. Kumele kuqashelwe ukuthi okubaluleke kakhulu phakathi kwabo ngamanani wokubala ama-bile acid. Lezi zingxube zisebenza njengama-emulsifying agents anamandla futhi, ngemuva kokufakwa emzimbeni, zingena esibindini, zisuka lapho zingasetshenziswa khona kabusha. Lezi zingxenye zinikeza ukugaya kanye nokuqhekeka kwamafutha avela ekudleni ngesikhathi sokugaya.
Mayelana ne-cholesterol metabolism ichazwe kuvidiyo kule ndatshana.
