Synapse Cholinergic: ukwakheka kwazo, imisebenzi

synapse Cholinergic kukhona indawo lapho kunokuxhumana phakathi izinzwa ezimbili noma amaseli neuronal kanye isignali effector eyamukelayo. I synapse yakhiwa ulwelwesi ezimbili - presynaptic futhi postsynaptic, kanye kusukela emfantwini izinhlaka zokuxhumana zobuchopho. Transmission Izinzwa amaza Kwenziwa esebenzisa umlamuleli, isb into Lidlulisela. Lokhu kwenzeka ngo-nokuxhumana yokwamukela futhi neurotransmitter ku ulwelwesi postsynaptic. Lona umsebenzi oyinhloko synapse cholinergic.

Umlamuleli futhi receptor

INdlu Yesishayamthetho Kazwelonke neurotransmitter parasympathetic kuyinto acetylcholine receptor - amabili izinhlobo receptor cholinergic: H (i-nicotine) kanye M (muscarine). M-cholinomimetics kokuba ngqo action hlobo zingase zibangele zemizwa postsynaptic ulwelwesi hlobo.

Synthesis acetylcholine wenziwa ku cytoplasm ka cholinergic eziyimpumelelo neuronal. Kumiswa It is kusukela choline futhi atsetilkoenzima-A, okuyinto has a umsuka mitochondrial. Synthesis kwenzeka ngaphansi isenzo cytoplasmic enzyme choline. I vesicles izinhlaka zokuxhumana zobuchopho kwenzeka sebethule acetylcholine. Esimweni ngasinye kulezi Bubbles kungenzeka kuze kube molecule ayizinkulungwane eziningana acetylcholine. I ngiyibona ezinzwa kuvusa ukukhululwa acetylcholine e amangqamuzana izinhlaka zokuxhumana zobuchopho emfantwini. Ngemva kwalokho, kungena nokuxhumana acetylcholine receptor. Isakhiwo cholinergic synapse esiyingqayizivele.

isakhiwo

Ngokusho idatha, okuyinto ziyatholakala biochemists, acetylcholine yokwamukela synapse kwamanyuroni ingase ihlanganise amaprotheni subunits ezinhlanu ezisizungezile isiteshi ion futhi wandise lonke ukushuba we ulwelwesi ehlanganisa lipid. Pair acetylcholine molecule uxhumana nge pair of α-subunits. Lokhu kuholela yokuthi kuvula isiteshi ion kanye ulwelwesi postsynaptic is depolarized.

Izinhlobo synapse cholinergic

receptor Cholinergic kuthiwa isebenze ngezindlela ezahlukene futhi okufanayo ngezindlela eziningi ezibucayi emiphumeleni ejenti kwemithi. Ngaphakathi accordance nga lo mahluko:

• Maskarinochuvstvitelnye receptor cholinergic - okuthiwa ama-receptor M-cholinergic. Ingabe i alkaloid inombolo muscarine esingokwemvelo amakhowe anobuthi, Amanita isibonelo.
• Nikotinochuvstvitelnye holinoretseptora - okubizwa ngokuthi ama-receptor H-cholinergic. I-nicotine kuyinto alkaloid ezitholakala amahlamvu ugwayi.

indawo yabo

Eyokuqala itholakala postsynaptic cell ulwelwesi yakhiwa effector izitho. Basuke sise eziyimpumelelo imicu postganglionic parasympathetic. Ngaphezu kwalokho, nabo babe kumaseli kwemizwa, ganglia autonomic futhi cortex cerebral. Kwatholakala ukuthi la mangqamuzana M-cholinergic ka kwasendaweni ezingefani heterogeneous, okuholela ukuzwela ezahlukene umongo synapse cholinergic imvelo kwemithi.

Izinhlobo kuye ngokuthi indawo

Biochemists kukhona izinhlobo eziningana receptor M-cholinergic:

• Akhiwe ganglia autonomic futhi uqondiswe isimiso sezinzwa esiyinhloko. Isici se-Esokuqala siwukuthi zitholakala ngaphandle kwe-synapse - receptor M1-cholinergic.
• Akhiwe enhliziyweni. Ezinye zazo ukukusiza ukwehlisa ukukhishwa acetylcholine - receptor M2-cholinergic.
• Akhiwe imisipha bushelelezi, futhi kweziningi nezindlala endocrine - la mangqamuzana M3-cholinergic.
• Akhiwe enhliziyweni, e ezindongeni alveoli yamaphaphu, e-CNS - receptor M4-cholinergic.
• Ibekwe CNS, e iris we iso, izindlala salivary, e egazi mononuclear - receptor M5-cholinergic.

Umthelela receptor cholinergic

Iningi imiphumela olunikezwa izinto kwemithi eyaziwa ezithinta la mangqamuzana M-cholinergic, ngenxa ukuxhumana lezi izinto futhi postsynaptic M2 kanye M3 receptor cholinergic.

Cabanga Ukwahlukaniswa izimali ukufukula synapse cholinergic ngezansi.

receptor H-cholinergic elise ulwelwesi we izinzwa postsynaptic e ganglia eziyimpumelelo ngayinye Imicu yotshani preganglionic (e ganglia parasympathetic nozwela), endaweni ye itheku carotid, ku medulla adrenal, e neurohypophysis, kumaseli Renshaw ezicutshini lwamathambo. Nozwela ezahlukene H-cholinergic receptor kuyahluka izinto. Ngokwesibonelo, ama-receptor H-cholinergic e autonomic izakhiwo ganglia (kokungathathi hlangothi uhlobo receptor) kukhona ukungezwani okukhulu kusukela receptor H-cholinergic ezicutshini lwamathambo (imisipha uhlobo receptor). Kuyinto lesi sici ivumela ukuba ngokukhetha ukuvimba ganglia izinto ezikhethekile. Ngokwesibonelo, kurarepodnye izidakamizwa uyakwazi ivimbela ukudluliselwa kwe-kwamanyuroni.

Presynaptic cholinergic receptor futhi adrenoceptors zinengxenye inqubo isiqondiso acetylcholine ukukhululwa ngesikhathi imvelo synapse neuroeffector. Ukukhuthazwa yalezi receptor ngabe zivimbela ukukhululwa acetylcholine.

Acetylcholine ihlangana H-acetylcholine receptor futhi siguqula conformation zabo, kwandisa ezingeni permeability we ulwelwesi postsynaptic. Acetylcholine kumqhubezela ku-athomu sodium, okuyinto ke ukungena esitokisini, futhi lokhu kuholela ekuphelelweni yokuthi ulwelwesi postsynaptic is depolarized. Ekuqaleni kukhona ezingaba wendawo izinhlaka zokuxhumana zobuchopho ezingase ifinyelela inani elithile, futhi uqala inqubo yokwenza isenzo ezingaba khona. Ngemva kwalokho, injabulo wendawo, okuyinto kukhawulwe endaweni zokuxhumana zobuchopho uqala sisabalale ulwelwesi cell. Uma kukhona ukukhuthazwa yokwamukela M-choline, indima ebalulekile eyadlalwa izithunywa wesibili kanye G-namaprotheni ukudluliswa isignali.

Acetylcholine izenzo ngesikhathi esifushane kakhulu. Lokhu kungenxa yokuthi it is ngokushesha hydrolyzed yi acetylcholinesterase enzyme. Choline, imiswe phakathi neminyaka hydrolysis acetylcholine emqulwini kwesigamu esibulalayo presynaptic okuyinto ishuthiwe futhi uyiswa cytoplasm ngoba biosynthesis okwalandela acetylcholine.

Izinto ukuthi isinyathelo synapse cholinergic

Kwemithi futhi ezihlukahlukene amakhemikhali kungaba nomthelela eziningi izinqubo okuhlotshaniswa ukudluliswa izinhlaka zokuxhumana zobuchopho:

• Inqubo acetylcholine zamagama.
• Inqubo umlamuleli ukukhululwa. Ngokwesibonelo, carbacholine uyakwazi ekuthuthukiseni acetylcholine ukukhululwa inqubo, ubuthi botulinum kungase kuthiye neurotransmitter ukukhululwa inqubo.
• Inqubo nokuxhumana phakathi acetylcholine futhi choline yokwamukela.
• Hydrolysis acetylcholine imvelo enzymatic.
• Ukuthunjwa choline, ezakhiwe hydrolysis acetylcholine esibulalayo presynaptic. Ngokwesibonelo, singavimbela gemiholiny ka namangqamuzana ezinzwa bamba futhi kuthuthwe ngendlela ephephile choline phakathi cytoplasm cell.

ngezigaba

Kusho inkanuko synapse cholinergic, anganikeza hhayi kuphela ukusebenza, kodwa anticholinergic (ezicindezelayo) umphumela. Njengesisekelo Ukwahlukaniswa izinto ezinjalo biochemists ukusebenzisa isiqondiso isinyathelo lezi compounds ku-receptor ezahlukene cholinergic. Uma banamathele isimiso esinjalo, izinto ezithinta la mangqamuzana cholinergic kungenziwa labizwa ngokuthi elandelayo:

• Izinto ezithinta ku-receptor M-cholinergic futhi receptor N-cholinergic: a holinomimetikami kukhona acetylcholine futhi carbacholine futhi holinoblokatoram - tsiklodol.
• ubunjalo anticholinesterase kusho. Lezi zinto zihlanganisa salicylate, physostigmine, Neostigmine, galantamine hydrobromide, Armin.
• Izinto ezithinta synapse cholinergic. Ngu cholinomimetics zihlanganisa pilocarpine hydrochloride futhi aceclidine ukuba holinoblokatoram - atropine sulfate, matatsin, tartrate platifillina, bromide ipratropium, hydrobromide skopalamina.

• Izinto nge vlinyanie receptor H-cholinergic. Ngu holinomimetikami kukhona tsititon futhi lobeline hydrochloride. H blocker nicotinic acetylcholine yokwamukela zingahlukaniswa ngamaqembu amabili. Eyokuqala - a kusho uhlamvu ganglioblokiruyuschimi. Lezi zihlanganisa benzogeksony, gigrony, pentamin, arfonad, pyrylium. Iqembu lesibili vkulyuchaet into Curariform. Lezi zihlanganisa imisipha relaxants, ukuhlinzeka isinyathelo neuropathy ezifana tubocurarine chloride, pancuronium bromide, pipekuroniya bromide.

Sahlola ngokuningiliziwe indlela ezithinta cholinergic synapse.