Lub cev tib neeg yog tsim los ntawm ntau lub hlwb. Lub cev thiab cov ntaub so ntswg yog ua los ntawm qee yam, thiab cov pob txha yog ua los ntawm lwm tus. Cov hlwb endothelial ua lub luag haujlwm loj hauv cov qauv ntawm cov hlab ntsha ntawm tib neeg lub cev.
Endothelium yog dab tsi?
Lub endothelium (los yog endothelial hlwb) yog ib qho khoom nruab nrog cev. Muab piv rau lwm tus, nws yog qhov loj tshaj plaws hauv tib neeg lub cev thiab kab cov hlab ntsha thoob plaws lub cev.
Raws li cov lus classical ntawm histologists, cov hlwb endothelial yog ib txheej, uas suav nrog cov hlwb tshwj xeeb uas ua haujlwm nyuaj biochemical. Lawv kab tag nrho cov hlab plawv los ntawm sab hauv, thiab lawv qhov hnyav nce mus txog 1.8 kg. Tag nrho cov xov tooj ntawm cov hlwb hauv tib neeg lub cev nce mus txog ib trillion.
Tam sim tom qab yug me nyuam, endothelial cell ceev nce mus txog 3500-4000 cells/mm2. Hauv cov neeg laus, daim duab no yuav luag ob zaug qis dua.
Thaum ntxov, cov hlwb endothelial tau suav tias tsuas yog qhov cuam tshuam tsis zoo ntawm cov ntaub so ntswg thiabntshav.
Cov ntawv uas muaj nyob hauv endothelium
Cov ntaub ntawv tshwj xeeb ntawm cov hlwb endothelial muaj qee yam qauv. Nyob ntawm qhov no, lawv paub qhov txawv:
- somatic (kaw) endotheliocytes;
- fenestrated (perforated, ntxeem tau, visceral) endothelium;
- sinusoidal (loj ntxeem tau, loj-qhov rais, kab mob siab) hom endothelium;
- lattice (intercellular slit, sinus) hom endothelial cells;
- siab endothelium hauv postcapillary venules (reticular, stellate type);
- endothelium ntawm lymphatic txaj.
qauv ntawm cov ntawv tshwj xeeb ntawm endothelium
Endotheliocytes ntawm somatic lossis kaw hom yog tus cwj pwm los ntawm qhov sib txawv ntom ntom, tsawg dua - desmosomes. Nyob rau hauv lub peripheral cheeb tsam ntawm xws li endothelium, lub thickness ntawm lub hlwb yog 0.1-0.8 µm. Nyob rau hauv lawv cov muaj pes tsawg leeg, ib tug tuaj yeem pom ntau micropinocytic vesicles (organelles uas khaws cov khoom muaj txiaj ntsig) ntawm cov ntaub so ntswg txuas ntxiv (cov cell uas cais cov ntaub so ntswg los ntawm endothelium). Hom kab mob endothelial no nyob rau hauv cov qog exocrine, hauv nruab nrab lub paj hlwb, lub plawv, spleen, ntsws, thiab cov hlab ntsha loj.
Fenestrated endothelium yog tus cwj pwm los ntawm nyias cov endotheliocytes, uas muaj los ntawm diaphragmatic pores. Qhov ceev hauv micropinocytic vesicles yog tsawg heev. Kuj tseem muaj qhov txuas hauv qab daus membrane. Feem ntau, cov kab mob endothelial no pom nyob rau hauv capillaries. Cov kab mob endothelial nocapillary txaj nyob rau hauv ob lub raum, endocrine qog, mucous daim nyias nyias ntawm lub digestive ib ntsuj av, choroid plexuses ntawm lub hlwb.
Qhov sib txawv tseem ceeb ntawm hom sinusoid ntawm vascular endothelial hlwb thiab tus so yog tias lawv intercellular thiab transcellular raws yog loj heev (txog 3 microns). Discontinuity ntawm hauv qab daus daim nyias nyias los yog nws tsis tiav yog yam ntxwv. Cov hlwb no muaj nyob rau hauv cov hlab ntsha ntawm lub hlwb (lawv koom nrog hauv kev thauj cov qe ntshav), lub cortex ntawm cov qog adrenal thiab lub siab.
Lattice endothelial hlwb yog qwj-zoo li tus (los yog spindle-puab) hlwb uas nyob ib puag ncig los ntawm lub hauv paus membrane. Lawv kuj koom nrog hauv kev tsiv teb tsaws ntawm cov qe ntshav thoob plaws hauv lub cev. Lawv qhov chaw nyob yog cov venous sinuses nyob rau hauv tus po.
Cov muaj pes tsawg leeg ntawm hom reticular ntawm endothelium suav nrog cov hlwb stellate uas cuam tshuam nrog cov txheej txheem cylindrical basolateral. Cov hlwb ntawm no endothelium muab kev thauj cov lymphocytes. Lawv yog ib feem ntawm cov hlab ntsha hla lub cev ntawm lub cev tiv thaiv kab mob.
Endothelial hlwb, uas pom nyob rau hauv lymphatic system, yog cov thinnest ntawm txhua hom endothelium. Lawv muaj cov qib lysosomes nce ntxiv thiab muaj cov vesicles loj dua. Tsis muaj daim pam hauv qab txhua qhov, lossis nws tsis txuas ntxiv.
Tseem muaj ib qho tshwj xeeb endothelium uas kab cov kab tom qab ntawm lub pob kws ntawm tib neeg lub qhov muag. Cov kab mob endothelial ntawm lub pob kws thauj cov kua dej thiab solutes mus rau hauv lub cornea thiab ua kom nws lub cev qhuav dej.
Roleendothelium hauv tib neeg lub cev
Endothelial hlwb, uas kab cov phab ntsa ntawm cov hlab ntsha los ntawm sab hauv, muaj lub peev xwm zoo: lawv nce lossis txo lawv cov lej, nrog rau qhov chaw raws li qhov xav tau ntawm lub cev. Yuav luag tag nrho cov ntaub so ntswg xav tau cov ntshav, uas nyob rau hauv lem nyob ntawm endothelial hlwb. Lawv yog lub luag haujlwm los tsim kom muaj kev txhawb nqa lub neej uas hloov tau yooj yim uas tawm mus rau txhua qhov chaw ntawm tib neeg lub cev. Nws yog ua tsaug rau qhov muaj peev xwm ntawm endothelium kom nthuav dav thiab rov ua haujlwm ntawm cov hlab ntsha ntawm cov hlab ntsha uas cov txheej txheem ntawm kev kho thiab cov ntaub so ntswg loj hlob tuaj. Yog tsis muaj nws, qhov txhab kho yuav tsis tshwm sim.
Yog li, cov hlwb endothelial hauv ob sab phlu tag nrho cov hlab ntsha (los ntawm lub plawv mus rau cov hlab ntsha me tshaj plaws) ua kom cov khoom nkag (xws li leukocytes) los ntawm cov ntaub so ntswg mus rau hauv cov ntshav thiab rov qab.
Tsis tas li ntawd, kev tshawb fawb hauv chav kuaj ntawm embryos tau pom tias tag nrho cov hlab ntsha loj (cov hlab ntsha thiab cov hlab ntsha) yog tsim los ntawm cov hlab ntsha me uas tau tsim tshwj xeeb los ntawm cov cell endothelial thiab hauv qab daus daim nyias nyias.
Endothelial functions
Ua ntej tshaj plaws, cov hlwb endothelial tswj hwm homeostasis hauv cov hlab ntsha ntawm tib neeg lub cev. Lub luag haujlwm tseem ceeb ntawm cov hlwb endothelial suav nrog:
- Lawv yog qhov thaiv ntawm cov hlab ntsha thiab cov ntshav, qhov tseeb, qhov chaw cia rau tom kawg.
- Cov kab no muaj kev xaiv permeability, uas tiv thaiv cov ntshav los ntawm cov khoom tsis zoo;
- Lub endothelium khaws thiab xa cov cim nqa los ntawm cov ntshav.
- Nws koom ua ke, yog tias tsim nyog, qhov chaw pathophysiological hauv cov hlab ntsha.
- Ua lub luag haujlwm ntawm tus maub los dynamic.
- Controls homeostasis thiab kho cov hlab ntsha puas.
- Txhim kho cov hlab ntsha.
- Lub luag haujlwm rau kev loj hlob thiab kho cov hlab ntsha.
- Ntawm biochemical hloov pauv hauv cov ntshav.
- Pom kev hloov pauv hauv cov pa roj carbon dioxide thiab cov pa oxygen hauv cov ntshav.
- Muab cov ntshav fluidity los ntawm kev tswj cov ntshav txhaws.
- Control ntshav siab.
- Cov hlab ntsha tshiab.
Endothelial dysfunction
Vim qhov tshwm sim ntawm kev ua haujlwm endothelial tuaj yeem tsim:
- mob ntshav siab;
- kev tsis txaus ntseeg;
- myocardial infarction;
- mob ntshav qab zib thiab insulin tsis kam;
- raum tsis ua haujlwm;
- mob hawb pob;
- kab mob plab plab.
Txhua yam kab mob no tsuas yog kuaj tau los ntawm tus kws tshaj lij xwb, yog li tom qab 40 xyoo, koj yuav tsum tau kuaj xyuas lub cev tsis tu ncua.
