Synapse - qhov no ... Lawv muaj ib lub synapse. Tshee, npag thiab tshuaj synapse

Synapse - ib tug txhais hu cheeb tsam ntoo ntawm cov hlab hlwb thiab lub seem uas tsis yog-excitable thiab excitable hlwb uas muab kis tau tus mob ntawm cov ntaub ntawv teeb liab. Synapse morphologically tsim hu week 2 hlwb. Lub membrane muaj feem xyuam rau cov appendages ntawm paj hlwb, hu ua lub presynaptic membrane ntawm ib tug cell, uas tau txais ib lub teeb liab, tus thib ob ntawm nws lub npe - postsynaptic. Nrog rau ua postsynaptic membrane tej zaum yuav interneuronal synapse, neuromuscular thiab neurosecretory. Lo lus ntawm lub synapse twb nkag tau rau hauv 1897 los ntawm Charles Sherrington (Eng. Physiologist).

Yuav ua li cas yog ib tug synapse?

Synapse - ib tug tshwj xeeb cov qauv, uas yuav muab kis tau tus mob ntawm paj fiber paj impulse mus rau lwm lub paj fibers los yog paj ntawm tes, thiab hais tias tshwm sim ntxim rau cov paj fiber los ntawm cov receptor cell (hu cheeb tsam nrog txhua lwm yam paj hlwb, thiab lwm yam neural fibers), ob tug paj hlwb yuav tsum tau .

Synapse - ib tug me me chaw ua hauj lwm nyob rau hauv lub kawg ntawm lub neuron. Nrog nws cov kev pab yog cov kev hloov ntawm cov lus qhia los ntawm tus thawj rau lub thib ob neuron. Synapse yog nyob rau hauv peb qhov chaw ntawm lub paj hlwb. Tsis tas li ntawd synapses yog nyob rau hauv lub qhov chaw uas paj cell los rau hauv kev twb kev txuas nrog txawv qog los yog nqaij ntshiv ntawm lub cev.

Yuav ua li cas nws yog nyob rau hauv lub synapse

Tus qauv ntawm lub synapse muaj ib tug yooj yim Circuit Court. Nws yog tsim nyob rau ntawm 3 daim, txhua tus uas tej kev khiav dej num yog ua thaum lub sij hawm cov ntaub ntawv kis tau tus mob. Yog li, xws li ib tug qauv yuav tsum tau hu ua ib tug synapse haum rau paj impulse kis tau tus mob. Ncaj qha rau tus txheej txheem ntawm cov lus qhia hloov lwm lub tsev muaj feem xyuam rau cov ob lub ntsiab hlwb: perceiving thiab kis. presynaptic terminals yog kis ntawm lub kawg ntawm axon hlwb (thawj zaug ib feem ntawm lub synapse). Nws yuav muaj feem xyuam rau lub cell mus pib lub neurotransmitters (lo lus no muaj ob peb lub ntsiab: kev sib kho sib kho los yog neurotransmitters) - tej yam tshuaj, uas nyob nruab nrab ntawm 2 neurons siv hloov lwm lub tsev ntawm qhov hluav taws xob lub teeb liab.

Synaptic cleft yog rau hauv nruab nrab ib feem ntawm synapses - yog ib tug ntev ntawm 2 reacts paj hlwb. Los ntawm no kis thiab nkag mus rau lub hlwb los ntawm kis ib tug hluav taws xob mem tes. Qhov kawg ib feem ntawm ib tug synapse yog xav tau txais ntawm lub cell, uas yog tus kawg ntawm postsynaptic (fragment hu hlwb nrog txawv rhiab receptors nyob rau hauv lawv cov qauv).

kev sib kho synapse

Tus Neeg Nruab Nrab (los ntawm lub Latin Media - transmitter, mloog ob tog los sis nruab nrab). Tej kev sib kho synapse qho tseem ceeb heev nyob rau hauv cov kis ntawm lub paj hlwb lam ua.

Morphological txawv ntawm inhibitory thiab excitatory synapses yog hais tias lawv tsis muaj ib tug tso tawm mechanism ntawm lub neurotransmitter. Tus Neeg Nruab Nrab nyob rau hauv lub inhibitory synapses, thiab lwm yam lub cev muaj zog neuron inhibitory synapses yog suav tias yog ib qho amino acid glycine. Tab sis tus nres los yog qhov exciting xwm ntawm lub synapse yog tsis yog txiav txim los ntawm lawv cov kev sib kho, thiab cov khoom teejtug uas yog cov postsynaptic membrane. Piv txwv li, acetylcholine muab stimulating nyhuv ntawm cov neuromuscular synapse terminals (vagus qab haus huv nyob rau hauv lub myocardium).

Acetylcholine yog lub neurotransmitter nyob rau hauv lub cholinergic excitatory neurotransmission (presynaptic membrane yog ua si qhov kawg ntawm cov leeg nrob qaum cev muaj zog neuron), nyob rau hauv lub synapse rau Renshaw hlwb mus rau hauv lub presynaptic davhlau ya nyob twg, tawm hws qog, medulla nadpochenikov nyob rau hauv cov hnyuv thiab synapse nyob rau hauv ganglia ntawm lub sympathetic lub paj hlwb. Atsetilholi-nesterazu thiab acetylcholine kuj muaj nyob rau ntawm ib feem ntawm qhov sib txawv qhov chaw ntawm lub paj hlwb, tej zaum nyob rau hauv loj tus xov tooj, tab sis lwm yam tshaj li cov cholinergic synapse rau hlwb Renshaw twb tsis tau muaj peev xwm kom paub tias cov seem cholinergic synapses. Raws li zaum, qhov exciting daws kho acetylcholine muaj nuj nqi nyob rau hauv lub central lub paj hlwb yog heev tej zaum yuav.

Katelhominy (dopamine, norepinephrine thiab epinephrine) pom tau hais tias adrenergic kev sib kho. Epinephrine thiab norepinephrine yog tsim nyob rau hauv lub tiav ntawm lub sympathetic paj nyob rau hauv lub hlwb adrenal cell, lub hlwb thiab tus txha caj qaum. Amino acids (tyrosine thiab L-phenylalanine) raws li cov pib tshuaj thiab synthesis ntawm adrenaline khoom zaum kawg. Intermediate yeeb tshuaj, uas muaj xws li norepinephrine thiab dopamine, kuj ua rau cov kev ua ntawm neurotransmitters nyob rau hauv lub synapse, tsim nyob rau hauv lub xaus ntawm qhov sympathetic qab haus huv. Qhov no muaj nuj nqi tej zaum yuav yog ib tug nres (plab hnyuv secretory caj pas, ob peb sphincters thiab bronchial du nqaij, thiab hnyuv) los yog excitatory (tus nqaij sphincters thiab tej hlab ntshav, myocardial synapse - norepinephrine, nyob rau hauv cerebral nuclei podkrovnyh - dopamine).

Thaum ua tiav lawv muaj nuj nqi ntawm synapse neurotransmitters, catecholamine absorbed los ntawm presynaptic paj xaus, thiab cov transmembrane thauj yog muaj. Thaum lub sij hawm haum muab kev sib kho synapses muaj kev tiv thaiv los ntawm ntxov ntxov havzoov tshaj ntev thiab du lag luam.

Synapse: theem pib hom thiab zog

Langley nyob rau hauv 1892, nws twb tau pom hais tias synaptic kis tau tus mob nyob rau hauv lub autonomic ganglia tsiaj tsis yog ib qho hluav taws xob, thiab tshuaj. Tom qab 10 xyoo, Elliott tau pom hais tias tus adrenaline los ntawm cov qog adrenal tau los ntawm cov tib los raws li lub stimulation ntawm lub sympathetic qab haus huv.

Tom qab ntawd assumed tias adrenaline peev xwm secreted los ntawm neurons li excitation thiab tso tawm los ntawm ib tug hlab ntsha xaus. Tab sis nyob rau hauv 1921, Levi ua cov kev kawm txawj, uas tau tsim muaj qhov xwm ntawm cov tshuaj kis tau tus mob ntawm synapses cov vegetative lub plawv thiab vagus qab haus huv. Nws sau cov qav plawv vessels nrog saline thiab tsa lub vagus paj, tsim ib tug qeeb plawv dhia. Thaum cov kua yog kis los ntawm cov inhibited mob stimulation nestimulirovanoe lub plawv yog ntaus maj mam. Kom meej meej, stimulation ntawm lub vagus paj los tso tawm retarding neeg sawv cev nyob rau hauv cov tshuaj. Acetylcholine siab cov me nyuam qhov teebmeem ntawm cov tshuaj yeeb dej caw. Nyob rau hauv 1930, lub luag hauj lwm ntawm acetylcholine nyob rau hauv lub synaptic kis tau tus mob nyob rau hauv ganglia ntawm lub autonomic lub paj hlwb mus tas li ntsia Feldberg thiab nws neeg ua hauj lwm.

tshuaj synapse

Cov tshuaj synapse yog fundamentally sib txawv kis tau tus mob voos nrog rau kev pab los ntawm ib tug neeg tuaj daws kho nrog presinapsa rau postsinaps. Yog li ntawd, cov txim hluav taws xob nyob rau hauv lub morphology ntawm cov tshuaj synapse. Cov tshuaj synapse yog ntau ntau nyob rau hauv vertebrate Cns. Nws yog tam sim no paub hais tias lub neuron yog tau cais tawm thiab coj los ua ke ib tug khub ntawm muab kev sib kho (kev sib kho coexisting). Neurons kuj muaj neurotransmitter plasticity - lub peev xwm los hloov loj kho kom haum xeeb thaum lub sij hawm txoj kev loj hlob.

Neuromuscular synapse

Qhov no synapse hau excitation, tab sis qhov no kev sib raug zoo muaj peev xwm zom ib tug ntau yam. Lub hloov lwm lub xaus thaum lub sij hawm ncaws ntawm lub blockade nyob rau hauv lub synaptic cleft acetylcholine, kuj thaum lub sij hawm nws raug txim nyob rau hauv excess ntawm lub cheeb tsam ntawm lub postsynaptic membrane. Ib tug plurality ntawm tshuaj lom tuag thiab tshuaj cuam tshuam capture, tso zis uas yog txuas mus rau acetylcholine receptors ntawm lub postsynaptic membrane, whereas nqaij synapse blocks cov kis ntawm excitation. Cov kab mob tuag thaum lub sij hawm txhawm chim thiab tsis txhob ua pa nqaij.

Botulism - microbial taug nyob rau hauv lub synapse, nws blocks cov kis ntawm excitation, shattering mus rau hauv lub presynaptic davhlau ya nyob twg protein syntaxin, nrog ib tug tawm los nyob rau hauv lub synaptic cleft acetylcholine. Ob peb kev sib ntaus los tej yam tshuaj lom ib pharmacologic agents (neostigmine methylsulfate thiab neostigmine), raws li zoo raws li tshuaj tua kab thaiv conduction ntawm excitation nyob rau hauv lub neuromuscular synapse siv inactivate acetylcholinesterase - ib qho enzyme uas lov acetylcholine. Yog li ntawd, muaj ib tug cia hnab khib acetylcholine nyob rau hauv lub synaptic membrane cheeb tsam txo rhiab heev rau tus Neeg Nruab Nrab, yog tau tawm ntawm postsynaptic week, immersion nyob rau hauv lub cytosol receptor unit. Acetylcholine yog ices, thiab lub synapse lawm.

Synapse tshee: nta thiab Cheebtsam

Synapse - ib tug kev twb kev txuas hu point ntawm ob lub hlwb. Thiab txhua yam uas lawv cov lus dag nyob rau hauv nws cov electrogenic membrane. Tshee synapse muaj peb lub ntsiab Cheebtsam: lub postsynaptic membrane, synaptic cleft thiab cov presynaptic membrane. Postsynaptic membrane - ib tug hlab ntsha xaus, uas extends rau cov nqaij thiab nws txo qis mus rau hauv tej nqaij. Nyob rau hauv lub cheeb tsam ntawm lub presynaptic hlwv nws yog - ib tug kaw kab noj hniav nrog ib tug neeg mloog ob tog. Lawv yog cov yeej ib txwm nyob rau hauv tsab ntawv tsa suab.

Nce cov daim nyias nyias ntawm cov hlab txoj, hlwv hauj lwm ua ke nrog nws, thiab tus Neeg Nruab Nrab ntog mus rau hauv lub synaptic cleft. Nyob rau hauv ib quantum neurotransmitter vesicle muaj mitochondria thiab (lawv yog tsim nyog rau lub synthesis ntawm cov neurotransmitter - thawj lub zog qhov chaw), ntxiv acetylcholine yog tsim los ntawm choline thiab nyob rau hauv tus ntawm lub enzyme atsetilholintransferrazy ua rau hauv atsetilSoA).

Synaptic cleft ntawm cov tom qab thiab presynaptic week

Nyob rau hauv sib txawv synapses luaj li cas ntawm cov kis txawv. Qhov no qhov chaw yog lawm ua tus sau nrog interstitial kua, nyob rau hauv uas muaj ib tug neeg tuaj daws kho. Postsynaptic membrane npog qhov chaw ntawm kev sib cuag nrog lub paj xaus nyob rau hauv lub innervated cell mionevralnom synapse. Nyob rau hauv tej yam synapses nyob rau hauv lub postsynaptic membrane tsim quav nce hu cheeb tsam.

Ntxiv tshuaj muaj nyob rau hauv lub postsynaptic membrane

Nyob rau hauv lub cheeb tsam ntawm lub postsynaptic membrane muaj cov nram qab no cov khoom xyaw:

- receptor (acetylcholine receptor nyob rau hauv mionevralnom synapse).

- lipoprotein (muaj ib tug high kev zoo sib thooj nrog acetylcholine). Qhov no protein yog tam sim no electrophilic kawg thiab ion lub taub hau. Lub taub hau nkag rau hauv lub synaptic cleft, ib tug kev sis raug zoo nrog cov cationic lub taub hau ntawm acetylcholine. Vim hais tias ntawm no sis yog ib tug kev hloov nyob rau hauv lub postsynaptic membrane depolarization ces tshwm sim, thiab qhia tawm uas nyob Na-raws. Depolarization ntawm daim nyias nyias yog tsis suav tias yog raws li ib tug self-reinforcing txheej txheem;

- Gradualen nws lub peev xwm rau cov postsynaptic membrane nyob rau hauv lub xov tooj ntawm kev sib kho, uas yog tsiag ntawv los ntawm cov vaj tse tej zaum ntawm lub zos excitations.

- Cholinesterase - xav tau ib protein uas muaj cov enzymatic muaj nuj nqi. Raws li cov qauv nws yog zoo li choline receptor thiab muaj zoo xws li cov khoom uas acetylcholine. Cholinesterase lov acetylcholine, ib tug thawj uas yog txuam nrog cholinergic receptors. Nyob rau hauv qhov kev txiav txim ntawm acetylcholine receptor tuskheej acetylcholine esterase tsim repolarization ntawm lub postsynaptic membrane. Acetylcholine cleaved rau choline thiab acetic acid tsim nyog rau tej nqaij trophism.

Nrog ib tug siv tau thauj yog tso tawm rau lub presynaptic membrane choline, nws yog siv coj los ua ke ib tug tshiab neurotransmitter. Nyob rau hauv tus ntawm lub neurotransmitter hloov nyob rau hauv lub permeability ntawm lub postsynaptic membrane, thiab ib tug cholinesterase rhiab heev thiab permeability rov qab mus rau thawj lub nqi. Chemoreceptors muab peevxwm koom tau nrog tus tshiab sib kho.