Yiziphi Ama-Glial Cell and What Do They Do?

Amanye ama-Cell Brain

Kungenzeka ukuthi wezwa "ngongcolile" yochungechunge, eyakhiwa ngamaseli abizwa ngokuthi ama-neurons, kodwa uhlobo oluthile oluthile lwama-brain cell yilokho okwenza "indaba emhlophe." Lezi zibizwa ngokuthi ama-glial cell.

Yiziphi Ama-Glial Cell?

Ekuqaleni, amangqamuzana e-glial-aphinde abizwa ngokuthi i-glia noma i-neuroglia-ayekholelwa ukuthi nje anikeze ukwesekwa kwesakhiwo. Igama elithi "glia" ngokwezwi nezwi lisho "i-neural glue." Nokho, ukutholakala okwakamuva nje kwembulani ukuthi benza zonke izinhlobo zobuchopho kanye nezinzwa ezigijima emzimbeni wakho wonke. Ngenxa yalokho, ucwaningo luye lwaqhuma futhi sifunde okuningi mayelana nabo. Noma kunjalo, okuningi kusele ukuze ufunde.

Izinhlobo zamaGlial Cell

Ngokuyinhloko, amaseli we-glial ahlinzeka ukusekela ama-neurons. Cabanga ngabo njengesizinda sokubhala isikhala sezinzwa zakho, kanye nabasebenzi be-janitorial and maintenance. Bangase bangenzi imisebenzi emikhulu, kodwa ngaphandle kwabo, leyo misebenzi emikhulu ngeke isenze.

Ama-glial cells afika ngamafomu amaningi, ngalinye liwenza imisebenzi ethile egcina ubuchopho bakho busebenza kahle-noma cha, uma unesifo esithinta lawa maseli abalulekile.

Isistimu yakho ye-central central (CNS) yenziwe ubuchopho bakho kanye nezinzwa zekholomu yakho yomgogodla. Izinhlobo ezinhlanu ezikhona ku-CNS yakho ziyi:

• Astrocytes
• Oligodendrocytes
• Microglia
• Amaseli e-Ependymal
• I-Radial glia

Futhi unamaseli we-glial ohlelweni lwakho lwesifo sezinzwa (PNS), olunezinzwa ezisemkhawulweni wakho, kude nomgogodla. Izinhlobo ezimbili zamaseli we-glial lapho kukhona:

• Amaseli e-Schwann
• Amaseli e-Satellite

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Astrocytes

Uhlobo oluvame kakhulu lwe-glial cell kwisistimu yezinzwa eziyinhloko yi-astrocyte, ebizwa nangokuthi i-astroglia. I-"astro" ingxenye yegama ngoba ibhekisela eqinisweni ukuthi ibukeka njengezinkanyezi, nemibono ephuma kuyo yonke indawo.

Amanye, okuthiwa ama-astrocyte ase-protoplasmic, anezilinganiso ezinzima ngamagatsha amaningi. Ezinye, okuthiwa ama-astrocyte enamafutha anezindebe ezinde, ezincane ezisebenza kancane kancane. Uhlobo lwe-protoplasmic luvame ukutholakala phakathi kwe-neurons enkingeni yegrey kuyilapho ama-fibrous atholakale enombala omhlophe. Naphezu kwalokhu umehluko, benza imisebenzi efanayo.

I-astrocytes inemisebenzi eminingana ebalulekile, kuhlanganise:

• Ukwakha ukuvinjelwa kwegazi-ubuchopho (BBB). I-BBB ifana nesistimu yokuphepha eqinile, ukuvumela kuphela izinto okufanele zibe ebuchosheni bakho ngenkathi ugcina izinto ezingase zibe yingozi. Loluhlelo lokuhlunga lubalulekile ekugcineni ingqondo yakho iphilile.
• Ukulawula amakhemikhali azungeze ama-neurons. Indlela i-neurons exhumana ngayo ngezithunywa zamakhemikhali okuthiwa i-neurotransmitters. Uma ikhemikhali isithumele umlayezo wayo esitokisini, ngokuyisisekelo ihlezi lapho kuhlanganiswa izinto kuze kube yilapho i-astrocyte ibuyisela kabusha inqubo ebizwa ngokuthi i- reuptake . Inqubo ye-reuptake ihlose imishanguzo eminingi, kuhlanganise nokulwa nokucindezeleka. Ama-astrocyte ahlanze futhi lokho okushiywe ngemuva uma i-neuron ifa, kanye ne-i-potassium ions eyengeziwe, okuyimikhemikhali edlala indima ebalulekile emsebenzini wezinzwa.
• Ukulawula ukugeleza kwegazi kuya ebuchosheni. Ukuze ubuchopho bakho buqhubekele ulwazi ngendlela efanele, kudinga inani elithile legazi eliya kuzo zonke izifunda zalo ezihlukene. Isifunda esisebenzayo sithola okungaphezu kokungasebenzi.
• Ivumelanisa umsebenzi we-axons. Ama-axx ayinde, izingxenyana ezinjengezingxube ze-neurons nama-cell we-nerve enza u-ugesi ukuthumela imilayezo kusuka kwesinye iseli kuya kwesinye.

Ukukhubazeka kwe-Astrocyte kuye kwaxhunyaniswa nezifo eziningi ze-neurodegenerative, kufaka phakathi:

• I-Amyotrophic lateral sclerosis (i-ALS noma isifo sikaLou Gehrig)
• I-chorea ka-Huntington
• Isifo sikaParkinson

Izibonelo zezilwane zezifo ezihlobene ne-astrocyte zisiza abacwaningi ukuba bafunde kabanzi mayelana nabo nethemba lokuthola amathuba amasha wokwelashwa.

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Oligodendrocytes

Ama-oligodendrocyte avela kuma-neural stem cells. Leli gama lenziwe ngamagama esiGreki athi, ndawonye, ​​asho "amangqamuzana anamagatsha amaningana." Inhloso yabo eyinhloko ukusiza ulwazi ukuhambisa ngokushesha nge-axons.

Ama-oligodendrocytes abukeka njengebhola le-spikey. On the tips of spikes zabo kukhona ezimhlophe, izimpande ezikhanyayo ezimboza ama-axons kumaseli wegazi. Inhloso yabo ukwakha ungqimba oluvikelayo, njenge-plastic insulation on wire wires. Lo ungqimba wokuzivikela ubizwa ngokuthi i-myelin sheath.

Umgogodla awuhlali njalo, noma kunjalo. Kukhona igebe phakathi kwebhulethi ngalinye elibizwa ngokuthi "i-node ye-Ranvier," futhi yi-node esiza izibonakaliso zikagesi ezisakaze kahle kahle amaseli wegazi. Isibonakaliso sisuke sisuka ku-node eyodwa kuya kwesilandelayo, okwandisa ukuqhutshwa kwe-nerve conduction kanti futhi ukunciphisa amandla angakanani okuwudlulisela. Izimpawu ezihamba ngezinzwa zomzimba zingasheshe zihambe ngamamitha angu-200 ngomzuzwana.

Lapho uzalwa, unama-axon ambalwa kuphela, futhi inani lawo liqhubeka likhula kuze kube yilapho uneminyaka engama-25 kuya ku-30 ​​ubudala. Ukukholelwa ekukholweni kuthathwa ukuthi kudlala indima ebalulekile ekuhlakanipheni.

Ama-oligodendrocyte nawo ahlinzeka ukuzinza futhi athathe amandla avela kumaseli egazi ukuya kuma-axons.

Igama elithi "i-myelin sheath" lingase lijwayele kuwe ngenxa yokuhlangana kwalo ne- multiple sclerosis . Kuleso sifo, bakholelwa ukuthi isimiso somzimba sokuzivikela somzimba sihlasela ama-myelin sheaths, okuholela ekusebenziseni ukungasebenzi kwalawo ma-neurons kanye nokusebenza kwengqondo engaphumeleli. Ukulimala kwentambo yomgogodla kungabangela umonakalo emagqabeleni ami.

Ezinye izifo ezikholelwa ukuthi zihlotshaniswa nokukhubazeka kwe-oligodendrocyte kufaka:

• Leukodystrophies
• Ama-Tumor abizwe nge- oligodendrogliomas
• I-schizophrenia
• Isifo se-bipolar

Olunye ucwaningo lubonisa ukuthi ama-oligodendrocyte angalimazwa yi-glutamate ye-neurotransmitter, okuyinto phakathi kweminye imisebenzi evuselela izindawo zobuchopho bakho ukuze ukwazi ukugxila nokufunda ulwazi olusha. Kodwa-ke, emazingeni aphakeme, i-glutamate ibhekwa ngokuthi "i-excitotoxin," okusho ukuthi ingaba ngaphezu kweminye amaseli kuze kube sekufeni.

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Microglia

Njengoba igama labo liphakamisa, ama-microglia amancane amangqamuzana we-glial. Benza njengamasosha omzimba azinikezele ebuchosheni, okudingekayo kusukela i-BBB ihlukanisa ubuchopho emzimbeni wakho wonke.

I-Microglia iyaqaphela izibonakaliso zokulimala nezifo. Lapho bekubona, bayangena futhi banakekele inkinga-kungakhathaliseki ukuthi kususa amaseli afile noma ukulahla i-toxin noma i-pathogen.

Lapho bephendula ekulimazeni, i-microglia ibangela ukuvuvukala njengengxenye yenqubo yokuphulukisa. Kwezinye izimo, ezifana nesifo se-Alzheimer , angase abe ne-hyper-activated futhi abangele ukuvuvukala okuningi. Kukholelwa ukuthi kuholele emagcekeni ama-amyloid nezinye izinkinga ezihlobene nesifo.

Ngokuhambisana ne-Alzheimer's, izifo ezingase zihlotshaniswe nokukhubazeka kwe-microglial zifaka:

• I-Fibromyalgia
• Ubuhlungu obungapheli be-neuropathic
• Ukuphazamiseka kwe-Autism spectrum
• I-schizophrenia

I-Microglia ikholelwa ukuthi inemisebenzi eminingi ngaphesheya kwalokho, kufaka phakathi izindima zokufunda nge-plasticity ehambisana nokufunda nokuqondisa ukuthuthukiswa kobuchopho, lapho kunomsebenzi obalulekile wokugcina indlu.

Ubuchopho bethu budala ukuxhuma okuningi phakathi kwe-neurons evumela ukuba badlulise ulwazi emuva nangaphezulu. Eqinisweni, ubuchopho budala okuningi kakhulu kunalokho esikudingayo, okungeyona ephumelelayo. I-Microglia ithola ama-synapses angadingekile futhi "uyayiphonsa," njengoba nje nomgadi wezithombo ehlwanyela i-rose bush ukuze agcine enempilo.

Ucwaningo lwe-Microglial luye lwaqeda ngempela eminyakeni yamuva, okuholela ekuqondeni okwandayo kwezindima zabo kokubili ezempilo nezifo ohlelweni lwezinzwa zomphakathi.

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Amaseli Ependymal

Amaseli e-Ependymal ayaziwa ngokudala i-membrane ebizwa ngokuthi i-ependyma, eyilungu elincane elincane elihlanganisa umsele ongaphakathi womgogodla kanye ne-ventricles (imizila) yobuchopho. Bakha futhi uketshezi lwe-cerebrospinal .

Amaseli e-Ependymal amancane kakhulu futhi ahlangane ngokuqinile ukuze enze i-membrane. Ngaphakathi kwe-ventricles, bane-cilia, ebukeka njengezinwele ezincane, ezogagagagudla emuva ukuze zithole uketshezi lwe-cerebrospinal olujikelezayo.

I-Cerebrospinal fluid inikeza izakhi zomzimba futhi iqede imikhiqizo yokudoba ebuchosheni nasendlwaneni yomgogodla. Ibuye isebenze njengendlela yokuxubha nokushaqeka phakathi kobuchopho bakho nekhanda. Kubalulekile futhi ukuba i-homeostasis yobuchopho bakho, okusho ukulawula ukushisa kwayo nezinye izici ezigcina isebenzayo ngangokunokwenzeka.

Amaseli e-Ependymal nawo ahilelekile ku-BBB.

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I-Radial Glia

I-Radial glia ikholelwa ukuthi iyinhlobo ye- stem cell , okusho ukuthi idala amanye amaseli. Ebuchosheni obusakhulayo, bangabantu "abazali" be-neurons, astrocytes, nama-oligodendrocytes. Ngesikhathi usuyi-embryo, futhi wanikezela i-scaffolding ye-neurons ethuthukayo, ngenxa yamafayili amade aqondisa amangqamuzana amancane obuchopho endaweni lapho ubuchopho bakho bubumba khona.

Indima yabo njengama-stem cells, ikakhulukazi njengabadali bama-neurons, enza ukuba kugxilwe ucwaningo mayelana nokulungisa ukulimala komqondo ngokugula noma ukulimala.

Kamuva empilweni, badlala indima ekusebenziseni i-neuroplasticity kanye.

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Ama-Schwann Amaseli

Amaseli aseSchwann abizwe ngokuthi yi-physiologist uTheodor Schwann, owathola. Zisebenza okuningi njenge-oligodendrocytes ngokuthi zinikeza ama-myelin sheaths ama-axons, kodwa zikhona ohlelweni lwezinzwa zomzimba (PNS) kune-CNS.

Kodwa-ke, esikhundleni sokuba iseli eliphakathi nezikhali eziboshwe nge-membrane, amaseli kaSchwann akha ama-spirals ngokuqondile azungeze i-axon. Amanothi kaRarvier alala phakathi kwabo, njengoba enza phakathi kwezingqimba zama-oligodendrocyte, futhi asiza ekudluliseni kwegazi ngendlela efanayo.

Amaseli e-Schwann nawo ayingxenye yesistimu yomzimba ye-PNS. Uma iseli lezinzwa lilimazekile, banamandla oku, ngokuyinhloko, adle ama-axon wezinzwa futhi banikeze indlela evikelwe ye-axon entsha ukwakha.

Izifo ezibandakanya amaseli e-Schwann zihlanganisa:

• I-Guillain-Barre 'syndrome
• Isifo se-Charcot-Marie-Tooth
• Schwannomatosis
• Ukuphefumula okungapheliyo kokudumala kwe-polyneuropathy
• Uchoko

Sithole ucwaningo oluthenjisayo mayelana nokufakelwa kabusha amaseli e-Schwann wokulimala komgogodla kanye nezinye izinhlobo zomonakalo wezinzwa zomzimba.

Amaseli e-Schwann nawo afaka phakathi kwezinye izinhlobo zobuhlungu obungapheliyo. Ukusebenza kwazo ngemuva kokulimala kwamantongomane kungabangela ukungasebenzi ngendlela efana ne- nociceptors , okuyizinto ezibonakalayo eziphathelene nokushisa nokubandayo.

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Amaseli esathelayithi

Amaseli e-Satellite athola igama lawo endleleni azungeze ngayo ama-neurons athile, aneziphakeli eziningana ezakhiwa umgodi ezungeze iselula. Sisaqala ukufunda ngalawa maseli kodwa abacwaningi abaningi bakholelwa ukuthi bafana nama-astrocytes.

Inhloso esemqoka yamaseli aseThalamende kubonakala sengathi isimiso semvelo ezungeze ama-neurons, ukugcina amakhemikhali ngokulingana.

Ama-neurons anama-satellite cell akha into okuthiwa i-gangila, engamaqoqo amangqamuzana e-nervous system ohlelweni lwe-autonomic ne-system sensory. Isistimu ye-neon autonomic ilawula izitho zangaphakathi zakho, ngenkathi isistimu yakho yezinzwa ikuvumela ukuthi ubone, uzwe, uzwe, uthinte, futhi unambithe.

Amaseli esathelayithi anika ukudla okunomsoco ku-neuron futhi athola amakhemikhali ensimbi anzima, afana ne-mercury nomthofu, ukuze angawavimbeli ama-neurons.

Bakholelwa ukuthi bazosiza ukuthutha ama-neurotransmitter amaningana nezinye izinto, kufaka phakathi:

• I-Glutamate
• IGABA
• I-Norepinephrine
• I-Adenosine triphosphate
• Izinto P
• I-Capsaicin
• I-Acetylcholine

Njenge-microglia, amangqamuzana e-satellite athola futhi aphendule ukulimala nokuvuvukala. Kodwa-ke, indima yabo ekulungiseni umonakalo wamangqamuzana akukaqondwa kahle.

Amaseli esathelayithi axhumene nobuhlungu obungapheli obubandakanya ukulimala kwezicubu zomzimba, ukulimala kwamantongomane, nokukhulisa ubuhlungu (hyperalgesia) obuhlelekile obungabangela i-chemotherapy.

Izwi elivela

Okuningi kwalokho esikwaziyo, sikholelwa, noma sikholelwa ngamaseli we-glial ulwazi olusha. Lawa maseli asisiza ukuthi siqonde ukuthi ubuchopho busebenza kanjani nokuthi kwenzekani uma izinto zingasebenzi ngendlela efanele.

Siyaqiniseka ukuthi sinezinto eziningi zokufunda nge-glia, futhi kungenzeka sithole izindlela ezintsha zokwelashwa ngezifo eziningi njengoba idamu lethu lolwazi likhula.

> Imithombo:

> Gosselin RD, Suter MR, Ji RR, i-Decosterd I. I-Glial cells kanye nobuhlungu obungapheli. I-Neuroscientist. 2010 Oct; 16 (5): 519-31.

> Kriegstein A, Alvarez-Buylla A. Imvelo ye-glial yama-embryonic and adult neural stem cells. Ukubuyekeza kwonyaka we-neuroscience. 2009; 32: 149-84.

> Ohara PT, Vit JP, Bhargava A, Jasmin L. Ubufakazi bendima yeConnexin 43 e-Trigeminal Pain Ukusebenzisa i-RNA Interference In Vivo. I-Journal ye-neurophysiology. 2008 Dec; 100 (6): 3064-73.