Indlela iinqwelo zeeMfuno ezizodwa zilawula ngayo uxinzelelo lwegazi
Iimitha zegazi ziyimithambo yegazi ephethe igazi elenziwe nge-oksijini ngaphandle kwentliziyo. Njengoko behamba ngeenethiwekhi zomnatha, bancinci kwaye bancinci njengamagatsha omthi. Xa ziye zinciphisa ngobukhulu ukuya kuma-micrometer angama-300 (μm), sibhekisela kuzo njenge-arterioles.
IArterioles yabelana ezininzi zeempawu zeetriyri. Zomeleleyo, zineendonga ezininzi, kwaye ziqulethe ipesenteji ephezulu ye-muscle elula.
Kodwa, bakhonza omnye umsebenzi obalulekileyo. I-Arterioles, eqinisweni, imithwalo yegazi elawulwa kakhulu emzimbeni kwaye igalelo elikhulu ekunyuseni nasekuwa kwexinzelelo lwegazi .
Njengeqela, i-arterioles iyaphendula kwimimandla ehlukahlukeneyo yamakhemikhali kunye nombane ovela kwingqondo, kwi-immune system, kunye ne- endocrine inkqubo kwaye ihlala ishintsha ngobukhulu ngokuphendula loo miyalezo. Ngokwenza njalo, ukuhamba kwegazi kunokukhawulezisa okanye kuphuculise, kubangele utshintsho oluthile kwixinzelelo legazi.
Ukulandelela ukuhamba kweGazi
Inkqubo ye- circulatory ithathwa njengeyivaliwe ngaphandle kokuba igazi lingaze lihambe kwiintambo zesistim. Kwizona zinto ziphambili, inkqubo leyo iqala kwaye iphele entliziyweni, ihambisa iamolekyuli ze-oksijeni ngaphandle kohambo kwaye ithwale i-carbon dioxide ekuhambeni kwangaphakathi.
Umzila wangaphandle uqala njengoko intliziyo igxotha igazi nge-aorta kwaye iyaqhubeka igawula njengoko igazi lenza indlela encinci yemithambo yegazi ebizwa ngokuba yi- capillaries .
Ngaphambi koku, igazi kufuneka lidlule kwi-arterioles apho isantya sawo soloko sihlengahlengiswa khona. Ezi zihlengahlengiso zinokuthi naziphi na izizathu ezibandakanya ukunyuka okanye ukuwela kumashishini obushushu, utshintsho kwimisebenzi yomzimba, ukutya , ukuxinezeleka , okanye ukuchazwa kwiibhox okanye amayeza.
Ngoko ke umsebenzi we-arterioles, ngoko ke, ukulawula uxinzelelo lwegazi ukuze luhlale lugxininisekile kwaye lungahle lutshintshe.
Ngokwenza njalo, igazi aliyi kuphinda lihluthe njengoko lifikelela kuma-capillaries. Esikhundleni salo, ukuhamba kwamanzi kuya kuqhubeka ngokuqhubekayo, ukuvumela ukutshintshisana okukhoyo kwe-oxygen kunye ne-carbon dioxide molecules.
Xa utshintshiselwano luphelile, igazi liza kwenza uhambo lwangaphakathi ngethungelwano lweemvini, ekugqibeleni libuyele entliziyweni ngokusebenzisa i-vena cava engaphantsi kwaye iphezulu.
I-Arteriole Disorders
Xa umzimba usebenza ngendlela efanelekileyo, i-arterioles inceda ukuqinisekisa ukuba uxinzelelo lwegazi luhlala luqhelekileyo kwimimiselo enempilo. Nangona kunjalo, kukho iimeko ezinokuchaphazela okanye zokuphazamisa ukusebenza kwazo. Phakathi kwabo:
- I-Arteriosclerosis yi-thickening, ilukhuni, kunye nokulahlekelwa kwe-elasticity yeendonga zokuguquka. Le nkqubo inqanda amandla e-arteriole ukulawula ukuhamba kwegazi kwaye ivumela ukuba i-accumque ye-plaque kunye ne-cholesterol kwiindonga zobushushu. Izimbangela ezintathu eziphambili ze-arteriosclerosis ziphezulu ze-cholesterol, i-triglycerides ephezulu, ukutshaya ugwayi, kunye nokunyuka kwegazi.
- I-stenosis ye-Arterial i-narrowening of the arteries. Oku kunokubangelwa naliphi na inani lezinto kuquka ukucoceka, ukutshaya, isifo sikashukela, ukusuleleka, kunye neziphene zokuzalwa. Ngokukodwa, i-constriction eqhubekayo yemithambo yegazi ngenxa yokungcola okanye ukusuleleka kwintsholongwane engapheliyo ingakhokelela ekubambeni kwezinto ezihamba phambili (fibrosis) zezicubu zomzimba.
- U-Arteritis ukuvuvukala kweendonga zobungqingili kunye nokujikeleza isikhumba, ngokuqhelekileyo kudibana nezifo ezizimele . Ukuvuvukala kweendonga zobungqina kubangela ukuhla kwegazi. Umzekelo oyintloko ngowama -cell arteritis amakhulu (GCA) echaphazela amagatsha omnquba we-carotid wangaphandle entanyeni. Nge-GCA, ukuhamba kwegazi okungapheleleki kunokubangela iimpawu zentloko, ukuguqulwa kombono, ukulahleka kombono, kunye nobuhlungu bentambo xa uhlafuna.
ILizwi
Ukuba ufumene unyango lwegazi oluphezulu, kufuneka ufune unyango loogqirha onokukubeka kwimishanguzo engaphelelanga . Nangona uvakalelwa kakuhle kwaye ungenayo impawu, ukuba khona kweengcinezelo zegazi kunokwandisa umngcipheko wokuhlaselwa kwentliziyo kunye nesifo.
Yingakho uxinzelelo lwegazi oluphezulu lubizwa ngokufanelekileyo ngokuthi "umbulali ongenangqondo."
> Imithombo:
> Lehmann, M. kunye noSmimieder, R. "Ukulungiswa kwemithambo emincinci ye-retinal kwi-hypertension," i- J J Hypertens. 2011; 24 (12): 1267-73. INGXELO: 10.1038 / ajh.2011.166.
> Nobel, A .; Johnson, R .; Bass, P. et al. (2010) Isistim se-Cardiovascular System (Esibini Ed.) . London: Churchill Livingstone / Elsevier. ISBN: 9780702050824.