I-Catecholamines ayilutho ngaphandle kwama-neurotransmitters, umqondo esizowukhuluma ngokuhamba kwesikhathi, lawa aziwa ngama-aminohormones. Incazelo i-etymological I-Catecholamine ingachazwa kanjena: Ziyiqembu lezinto lapho i-adrenaline, i-norepinephrine ne-dopamine kungashiwo khona, lezi zinto zihlanganiswa zisuka ku-amino acid eyaziwa ngokuthi i-tyrosine, yile ndlela eyakhiwa ngayo iqembu le-catechol neqembu Not mina.
Ngalo mqondo, ama-catecholamines (i-CA) noma ama-aminohormones kungashiwo ukuthi yizo zonke lezo zinto eziqukethe esakhiweni sazo iqembu le-catechol kanye nohlu oluseceleni neqembu lama-amino. Zingasebenza emzimbeni wethu njengamahomoni noma njengama-neurotransmitters.
Kepha iyini ngempela i-neurotransmitter?
Le ncazelo ingathathwa njengokhiye wokuqonda konke okuphathelene ne-catecholamine. Ngalo mqondo, i-neurotransmitter ingachazwa njengohlobo lwe neuromediator noma umyalezo, kushiwo ngendlela yesayensi, i- i-biomolecule eyenza i-neurotransmission ukuthi yenzeke.
Kuyini i-neurotransuction?
Akuyona into ngaphandle kokudluliswa kolwazi kusuka ku-neuron, okungukuthi, iseli lohlelo lwemizwa oluya kwenye i-neuron, iseli lemisipha noma indlala, konke lokhu kutholakala nge-synapse, okuyigatsha elibahlukanisayo . AmaCatecholamine enza umsebenzi wehomoni njengoba ekhiqizwa kwizindlala ze-adrenal futhi futhi ekugcineni kwezinzwa, ngakho-ke babhekwa njengama-neurotransmitters.
Eyokuqala yazo yonke i-tyrosine, esetshenziswa njengomthombo kuma-catecholaminergic neurons (abakhiqizi be-catecholamine). Lokhu kunemvelaphi yazo ikakhulukazi kumaseli e-chromaffin we-adrenal medulla nasezintanjeni ze-postganglionic zesistimu yezinzwa ezwelayo.
Kukhona ama-catecholamine: i-norepinephrine ne-dopamineZisebenza njengama-neurotransmitters kuCentral Nervous System futhi njengama-hormone egazini. AmaCatecholamine ngokuvamile akhiqiza izinguquko zomzimba ezilungiselela umuntu nomzimba ukulwa nezinye izinto zomzimba.
Ubudlelwano nezifo ezithile
Ucwaningo selukhombise isikhathi eside ukuthi ukungasebenzi kahle ezindleleni ze-catecholaminergic kungenxa yokuphazamiseka kwe-bipolar kanye ne-schizophrenia. Ngenkathi isebenza ngemoto, i-dopamine ibandakanyeka kwisifo sikaParkinson.
Yile ndlela okwakhiwa ngayo i-catecholamine
I-Catecholamine biosynthesis inqubo elawulwa kakhulu. Ukulawulwa kwesikhathi eside kuvame ukufaka inani lama-enzyme wokulawula. Ilawula inani le-tyrosine hydroxylase, kanye nenani le-dopamine? -Hydroxylase. Kwesinye isikhathi kudingeka izinguquko zesikhashana, futhi zilawulwa ngezinqubo ezahlukahlukene:
I-enzyme evuselela isigaba sokunciphisa amazinga (iTyrosine hydroxylase) kuvinjelwe i-Dopa ne-dopamine, ngoba bancintisana ne-biopterin yezindawo zokubopha.
Ukulawulwa kwe-tyrosine hydroxylase nge-phosphorylation. Esiqeshaneni ngasinye kunezinsalela ze-serine (izikhundla 8, 19, 31, 40) ezifakwe phosphorylated. Izinsalela ze-Serine 19 no-40 zidala ukwanda okuphawuleka kakhulu komsebenzi lapho zenziwe i-phorylated. Izinsalela ezingama-40 zenziwe i-phosphorylated ngokuyinhloko yi-protein kinase A, ne-10 yi-CAM kinase II. Ukudonswa kwetheminali kukhulisa umsebenzi we-tyrosine hydroxylase, njengoba kungena i-calcium esebenze i-kinase enzyme.
Lapho nje ama-catecholamine esenziwe, agcinwa ngaphakathi kwama-vesicles we-synaptic aziwa njenge-granular noma aminyene ama-vesicle vesicles. Ngaphakathi kuma-vesicles kukhona izinto ezibizwa ngama-chromogranins, calcium ne-ATP ekugxileni okuphezulu (1000 mM). AmaCatecholamine ayinkimbinkimbi nama-chromogranins.
Kukhona ne-dopamine? -Hydroxylase, yingakho ukuhlanganiswa kwe-norepinephrine kwenzeka ngaphakathi kwe-gallbladder, okungenani ngokwengxenye. Uhlelo ama-catecholamines angena ngalo kuma-vesicles uhlelo lwe-proton antiport system. I-proton gradient edingekayo yenziwa yi-proton-ATPase edonsa ama-proton kuwo, ngakho-ke i-pH icishe ibe ngu-5,5. Lolu hlelo lokutholwa lunokucaciswa okubanzi kwe-substrate. Ngakho-ke bangancintisana nama-catecholamines endogenous.
Inqubo yokukhipha ama-catecholamine
Kunezinqubo ezahlukahlukene ezibalulekile ekukhishweni kwama-catecholamines, okokuqala sinama-adrenergic receptors (norepinephrine kanye ne-adrenaline): Lawa ma-neurotransmitter amabili anemiphumela ehlukile, echazwa ngokuba khona kwama-receptors ahlukene, atholakala ohlotsheni ngalunye lweseli kuhlanganiswe ezindleleni ezahlukahlukene zokudlulisa.
Kuma-muscle abushelelezi kungaveza ukusikeka uma ama-Receptor enziwe asebenza, futhi akhululeke uma enza ngokuvumelana nama-2 receptors. Emithanjeni yegazi bakhiqiza i-vasoconstriction ne-vasorelaxation.
Kodwa-ke, okuphambene nemikhumbi, ku-bronchi kuveza ukuqaqanjelwa komzimba. Ngenkathi kusendleleni yokugaya ukudla kubanga ukucinana nokuphumula. Ngokushesha uma inhliziyo inyusa izinga lokushaya kwenhliziyo nokuqina kwayo; ukwandisa ukuphuma kwenhliziyo.
Ama-adrenergic receptors ahlobene ngokwakhiwa, kepha anezithunywa ezihlukile zesibili. Ngabe ama-receptors ahlukile? Y?; I-Epinephrine ne-norepinephrine ngama-agonists kuwo womabili ama-receptors, kepha lawa anama-agonists amaningi nabaphikisi. Umamukeli? kungaba? 1 noma? 2. I? 1 kungaba u-A, B, noma u-D.
Lokhu okuthathu kuyehluka kubaphikisi, indawo, ukwakheka, kanye nendlela yokwenza (adenylate cyclase). Kulokhu, okubalulekile ukuthi i-adenylate cyclase ibangela umphumela ohlukile kusayithi ngayinye emzimbeni. I? zingaba ngu-1, 2 noma u-3. Ziyahluka kubaphikisi, nezimpawu. Kepha konke oku-3 kukhuthaza i-adenylate cyclase.
Ukubaluleka ekusebenzeni kwansuku zonke komzimba womuntu
La ma-neurotransmitters amele ukubaluleka okukhulu ezenzweni zomzimba wethu, ngoba zinemisebenzi eminingi. Babamba iqhaza kuzo zombili izindlela ze-neural ne-endocrine.
Enye yalezi zithonya yilezi abazisebenzisayo ohlelweni lwezinzwa olulawulayo ukuhamba, ukuqonda, imizwa, ukufunda nokukhumbula. Ngokuphathelene nengcindezi, ama-catecholamine adlala indima ebalulekile ekuphenduleni kuwo, ekhipha lezi zinto lapho ubhekene nokucindezeleka ngokomzimba noma ngokomzwelo.
Ngo-1990 abacwaningi banquma ukuthi ezingeni lamaseli, lezi zinto zilinganisa umsebenzi we-neuronal ngokuvula noma ukuvala iziteshi ze-ion ngokuya ngama-receptors abandakanyekile.
Kunqunywa kanjani ukuba khona kwayo?
Amazinga eCatecholamine anganqunywa ngokutadisha nokuhlola igazi nomchamo. Eqinisweni, ama-catecholamine aboshelwe cishe kumaphesenti angama-50 wamaprotheni asegazini.
Lapho ukwehluleka noma ukwehla kwe-catecholamine neurotransmission kwenzeka, izinkinga ezithile ze-neurological ne-neuropsychiatric zenziwa. Esinye sazo ukucindezeleka, okuhambisana nakho amazinga aphansi alezi zinto, ngokungafani nokukhathazeka. Ngakolunye uhlangothi, i-dopamine ibonakala idlala indima ebalulekile ezifweni ezinjengeParkinson's kanye ne-schizophrenia.
Ekugcineni, kubalulekile ukuqonda ukuthi amazinga e-catecholamine angaxhomeka kithi uma sithatha uhlobo oluthile lokudla olunenani elifanele lezinto ezishukumisa le neurotransmitter. Kukhona ukudla okunobukhona obuphezulu be-phenylalanine njengenyama ebomvu, amaqanda, inhlanzi, ubisi, ama-chickpeas, udali, amantongomane, njll.
Ku-aspartame, i-sweetener esetshenziswa kakhulu embonini yokudla, imele ngaphezu kwe-60% yemakethe yomhlaba yalezi zithasiselo ezisetshenziswa kakhulu eziphuzweni ezithambile nemikhiqizo yokudla, iyatholakala lapho. Ngenkathi i-tyrosine itholakala kushizi.
Kusenza sizizwe kanjani?
Zombili lezi zinto zisebenza njengama-hormone ahambisanayo. Lokhu kusho ukuthi balingisa imiphumela yokungasebenzi kahle ohlelweni lwezinzwa oluzwelayo.
Ngendlela yokuthi lapho lezi zinto zidedelwa zingene egazini, ukwanda komfutho wegazi, ukusikwa okukhulu kwemisipha, nokwanda kwamazinga eglucose kuyenzeka. Kanye nokusheshisa kokushaya kwenhliziyo nokuphefumula. Lokhu kuchaza ukuthi kungani ama-catecholamine ebaluleke kakhulu ekuphenduleni izimpendulo zokulwa noma zokundiza ekucindezelekeni.
Ukukhishwa kweCatecholamine
Ukuze kukhishwe ama-catecholamine, kudingeka kukhishwe i-acetylcholine. Lokhu kukhishwa kungenzeka, ngokwesibonelo, lapho sithola ingozi. I-Acetylcholine ingenisa i-adrenal medulla futhi ikhiqize uchungechunge lwemicimbi yeselula.
Lapho i-adrenaline iphakama, kukhuphuka amandla okubizwa ngokuthi yi-contractile enhliziyweni akhiqizwa. Ngaphezu kwalokho, imvamisa yokushaya kwenhliziyo iyanda. Lokhu kubangela ukwanda kokuphakelwa komoya-mpilo. Ngendlela efanayo, zandisa izinga lokuphefumula. Ngaphezu kwalokho, inemiphumela enamandla yokuphumula ye-bronchial.
Ekugcineni, kubalulekile ukuthi sazi ukuthi kusenza sisabele masishane uma sikhuthazeka nokuthi sifunde futhi sikhumbule kangcono. Kodwa-ke, amazinga aphezulu alezi zinto ahlanganiswe nezinkinga zokukhathazeka. Ngenkathi amazinga aphansi e-dopamine abonakala ethonya ukubukeka kokuphazamiseka ekubhekeni, ubunzima bokufunda nokudangala.