Synapses yog cov chaw tshwj xeeb ua haujlwm uas nyob nruab nrab ntawm cov hlwb uas ua rau muaj kev ntxhov siab. Lawv xa thiab hloov ntau yam teeb liab. Synapses tshwm raws li thickenings ntawm qhov kawg ntawm cov paj hlwb. Nrog lawv cov kev pab, paj hlwb impulses propagate mus rau cov nyob sib ze cell. Lub luag haujlwm tseem ceeb ntawm lub synapse yog kev sib kis ntawm cov paj hlwb.
Kev faib tawm thiab piav qhia luv luv
Raws li hom kev coj ua ntawm impulses, muaj kev sib xyaw, tshuaj thiab hluav taws xob synapses. Tshuaj kis tau tus mob ua lub teeb liab nyob rau hauv ib qho kev taw qhia thiab amplifies nws, thiab kuj depolarizes los yog hyperpolarizes lub postsynaptic sphere. Nrog kev pab los ntawm tshuaj synapses, plasticity nyob rau hauv cov teeb liab kis tau tus mob nce, uas yog, ib tug neeg txhim kho kev nco thiab kev kawm ceev. Tsis muaj synaptic qeeb hauv kev xa hluav taws xob, thiab lub teeb liab yog ua nyob rau hauv ob qho kev qhia. Impulse kis tau tus mob yog ywj siab ntawm qhov kev txiav txim ntawm presynaptic membrane. Tsis tas li ntawd, hluav taws xob synapses tiv taus qhov kub thiab txias, nrog rau qee qhov cuam tshuam los ntawmyam ntawm pharmacology. Synapses ntawm hom sib xyaw muaj ib qho tshwj xeeb. Lawv ua tshuaj lom neeg thiab hluav taws xob teeb liab kis tau tus mob nyob rau hauv parallel.
Dab tsi yog hluav taws xob synapse?
Hluav taws xob synapses yog intercellular formations, nrog kev pab los ntawm kev sib kis ntawm ib tug excitation impulse yog guaranteed. Cov txheej txheem no tshwm sim vim qhov tshwm sim ntawm hluav taws xob tam sim no ntawm ob lub tuam tsev hu ua presynaptic thiab postsynaptic. Lub paj hlwb ntawm invertebrates muaj ntau cov hluav taws xob synapses, thaum cov tsiaj txhu yuav luag tsis muaj. Ua ke nrog qhov no, hluav taws xob synapses muaj ntau ntawm cov tsiaj siab dua. Lawv feem ntau pom nyob rau hauv lub plawv, daim siab, cov leeg, thiab nyob rau hauv lub epithelium thiab glandular ntaub so ntswg. Qhov sib txawv ntawm synaptic hauv hluav taws xob synapses yog nqaim ntau dua li hauv cov tshuaj synapses. Ib qho tseem ceeb ntawm cov synapses no yog tias muaj cov txuas peculiar ntawm cov protein molecules ntawm pre- thiab postsynaptic membranes.
Kev ua haujlwm tseem ceeb ntawm hluav taws xob hom synapses
Cov khoom ntawm hluav taws xob synapses yog raws li hauv qab no:
- nrawm nrawm (ntau dua rau kev ua haujlwm hauv tshuaj lom neeg synapses);
- tsis muaj kab mob tshwm sim (tsis muaj qhov ua tau zoo los ntawm kev ua tiav pulses);
- txhim khu kev qha kis tau tus mob excitation;
- siab plasticity;
- kis tau tus mob hauv ib qho thiab ob qho kev qhia.
qauv nta
qauvCov hluav taws xob impulse pib los ntawm postsynaptic membrane. Tom ntej no yog ib tug nqaim synaptic cleft, uas muaj transverse tubules, uas muaj cov protein molecules. Tom qab lub cleft yog presynaptic membrane. Nyob rau hauv nruab nrab yog ib tug semicircular synaptic plaque. Lub oblong synaptic xaus yog qhov kawg ntawm cov qauv ntawm cov hluav taws xob synapse. Vim muaj cov kab ntawm cov protein molecules ntawm pre- thiab postsynaptic hlwb, inorganic ions thiab cov me me molecules muaj peev xwm txav los ntawm ib lub cell mus rau lwm tus. Xws li ib tug synapse muaj hluav taws xob tsawg heev. Raws li cov xwm txheej no, qhov tam sim no presynaptic txuas mus rau cov hlwb postsynaptic thiab xyaum tsis ploj mus.
Txoj haujlwm tshwj xeeb
Muaj ntau yam kev ua haujlwm tshwj xeeb hauv hluav taws xob synapses. Yeej tsis muaj synaptic ncua. Lub impulse tuaj txog ntawm qhov kawg presynaptic, tom qab uas cov txheej txheem ntawm postsynaptic muaj peev xwm tam sim ntawd pib. Tsis muaj ib ntus ntawm cov kev ua no. Hluav taws xob synapses muab kev sib kis ntawm ib tus txheej txheem - excitation. Hauv synapses ntawm hom no, kev coj ua yog ob sab, txawm tias qhov tseeb tias, vim muaj cov yam ntxwv stereometric, kev coj ua hauv ib qho kev coj ua tau zoo tshaj plaws. Ntau yam (pharmacological, thermal, thiab lwm yam) tsis muaj kev cuam tshuam rau hluav taws xob hom synapses.
Kev zoo siab kis mus rau hauv hluav taws xob synapses li cas? Cov txheej txheem
Excitation conduction (PD) yog lub luag haujlwm tseem ceeb ua los ntawm hluav taws xob synapse. Cov txheej txheem ntawm cov txheej txheem no hauv synapses zoo ib yam li AP hauv paj hlwb. Thaum qhov kev ua ntawm excitation dhau mus rau theem kev loj hlob, kev them nyiaj rov qab pib nyob rau hauv presynaptic membrane. Yog li ntawd, ib qho hluav taws xob tam sim no tshwm sim, uas cuam tshuam rau postsynaptic membrane, irritates nws thiab ua rau tiam ntawm AP nyob rau hauv nws. Kev ua ntawm excitation nyob rau hauv hluav taws xob synapses yog ib tug complex physiological txheej txheem uas mus rau hauv ob peb theem. Lub presynaptic daim nyias nyias hloov cov hluav taws xob impulse rau hauv ib qho tshuaj, uas, tsoo lub postsynaptic phaj, rov tig mus rau hauv hluav taws xob teeb liab.
Qee yam tsis xws luag hauv hluav taws xob synapses
Txawm hais tias qhov tseeb tias hluav taws xob synapses ua tiav cov txheej txheem yooj yim ntawm kev hloov pauv, lawv muaj ntau yam tsis xws luag. Thiab qhov stereotype ntawm lawv cov kev ua yog los liam rau qhov no. Tsis muaj qhov ua tau ncaj qha xa mus rau excitation mus rau cov hlwb nyob deb. Pre- thiab postsynaptic hlwb, uas txuas nrog hluav taws xob-hom synapses, yog tas li nyob rau hauv tib lub excitation. Qhov tsos ntawm inhibition yog tsis tau. Raws li qhov tshwm sim ntawm tag nrho cov kev tsis txaus siab saum toj no, tus menyuam lub hlwb tsis muaj hluav taws xob ntau, thaum nyob rau hauv ib tug neeg laus muaj ntau heev ntawm lawv nyob rau hauv lub retina, hlwb qia thiab cov hauv paus hniav ntawm lub vestibular apparatus.
Ib yam zoo sib xws, tab sis twb nyob rau hauv ib daim ntawv pathological, lub mechanism ntawm conduction ntawm excitation tshwm nyob rau hauvqhov tshwm sim ntawm cov kab mob uas cuam tshuam nrog degeneration ntawm axon ciam teb. Raws li qhov tshwm sim ntawm cov txheej txheem no, excitation "dhia" los ntawm ib qho axon mus rau lwm qhov, uas tuaj yeem ua rau muaj kev xav tsis tseeb. Piv txwv li, qhov tshwm sim ntawm kev hnov mob, txawm tias qhov tsis ua haujlwm ntawm peripheral mob receptors, tuaj yeem tshwm sim vim yog "dhia" ntawm excitation.
