I-Catecholamines ayikho enye into ngaphandle kwe-neurotransmitters, umbono esiza kuwujongisisa kamva, ezi zaziwa ngokuba zii-aminohormones. Inkcazo I-etymological I-Catecholamine inokuchazwa ngolu hlobo lulandelayo: Ziliqela lezinto apho kunokukhankanywa iadrenaline, norepinephrine kunye nedopamine, ezi zinto zidityaniswe zivela kwiamino acid eyaziwa njenge-tyrosine, yile ndlela yenziwe ngayo iqela leekatechol kunye neqela Not mna.
Ngale ndlela, ii-catecholamines (CA) okanye ii-aminohormones kunokuthiwa zizizo zonke izinto eziqulethwe kulwakhiwo lweqela lekati kunye nekhonkco elisecaleni kunye neqela le-amino. Banokusebenza emzimbeni wethu njengamahomoni okanye njengee-neurotransmitters.
Kodwa yintoni kanye kanye le neurotransmitter?
Le nkcazo inokuqwalaselwa njengesitshixo sokuqonda yonke into enento yokwenza ne-catecholamine. Ngale ndlela, i-neurotransmitter inokuchazwa njengohlobo lwe neuromediator okanye umyalezo, wathi ngendlela yenzululwazi ngu i-biomolecule eyenza ukuba i-neurotransmission ibekho.
Yintoni i-neurotransuction?
Ayisiyiyo enye into ngaphandle kokuhanjiswa kolwazi ukusuka kwi-neuron, oko kukuthi, iseli yenkqubo yemithambo-luvo eya kwenye i-neuron, iseli yemisipha okanye idlala, konke oku kufezekiswa nge-synapse, elilisebe elibahlulayo. . IiCatecholamines zinomsebenzi wehomoni njengoko ziveliswa kwincindi yeadrenal kwaye nakwiziphelo zentliziyo, ke zithathwa njengee-neurotransmitters.
Eyokuqala yazo yonke i-tyrosine, esetyenziswa njengomthombo kwii-catecholaminergic neurons (abavelisi be-catecholamine). Ezi zinemvelaphi yazo ikakhulu kwiiseli ze-chromaffin ze-adrenal medulla nakwimicu ye-postganglionic yenkqubo yemfesane enovelwano.
Kukho iikatekamine: norepinephrine kunye nedopamineBasebenza njengama-neurotransmitters kwiNkqubo yeNervous Central kunye ne-hormone egazini. IiCatecholamines ngokubanzi zivelisa utshintsho olwenzeka emzimbeni nolungiselela umntu ukuba alwe kwaye enze nezinye izinto zomzimba.
Ubudlelwane nezifo ezithile
Izifundo kudala zabonisa ukuba ukungasebenzi kakuhle kwiindlela ze-catecholaminergic kungenxa yokuphazamiseka kwengqondo kunye neschizophrenia. Ngelixa kwimisebenzi yeemoto, i-dopamine iyabandakanyeka kwisifo sika-Parkinson.
Le yindlela ekwenziwa ngayo i-catecholamine
ICatecholamine biosynthesis yinkqubo elawulwa kakhulu. Ummiselo wexesha elide uhlala ubandakanya isixa sem enzymes. Ilawula inani le-tyrosine hydroxylase, kunye nenani le-dopamine? -Hydroxylase. Ngamanye amaxesha utshintsho lwexesha elifutshane luyafuneka, kwaye zilawulwa ngeendlela ezahlukeneyo:
I-enzyme ebangela inqanaba lokunciphisa umda (tyrosine hydroxylase) kuthintelwe yi-Dopa kunye ne-dopamine, kuba bakhuphisana ne-biopterin kwiindawo ezibophayo.
Ummiselo we-tyrosine hydroxylase nge-phosphorylation. Kwisununithi nganye kukho iintsalela ze-serine (izikhundla 8, 19, 31, 40) ezi-phosphorylated. Iintsalela zeSerine 19 kunye ne-40 zibangela ukonyuka okubaluleke ngakumbi kwimisebenzi xa iphakanyisiwe. Iintsalela ezingama-40 ziphosphorylated ikakhulu yiprotein kinase A, kunye ne-10 yi-CAM kinase II. Ukupheliswa kwesiphelo sendlela kukonyusa umsebenzi we-tyrosine hydroxylase njengoko i-calcium ingena kwaye isebenzise i-kinase enzymes.
Nje ukuba ii-catecholamines zidityaniswe, zigcinwa ngaphakathi kwii-synaptic vesicles ezaziwa ngokuba zii-granular okanye i-dense nucleus vesicles. Ngaphakathi kwee-vesicles kukho izinto ezibizwa ngokuba yi-chromogranins, calcium kunye ne-ATP kuxinzelelo oluphezulu (1000 mM). IiCatecholamines zinzima kunye ne chromogranins.
Kukho ne-dopamine? -Hydroxylase, yiyo loo nto ukuhlanganiswa kwe-norepinephrin kwenzeka ngaphakathi kwenyongo, ubuncinci kwinxalenye. Inkqubo apho ii-catecholamines zingena khona kwi-vesicles yinkqubo ye-proton antiport system. Iproton proton gradient eyimfuneko yenziwa yiproton-ATPase yokumpompa iiproton kuyo, ke i-pH imalunga ne-5,5. Le nkqubo yokuthatha inendawo ebanzi engaphantsi. Ke banokukhuphisana neekatecholamines ezingapheliyo.
Inkqubo yokukhupha ii-catecholamines
Kukho iinkqubo ezahlukeneyo ezingundoqo ekukhutshweni kweekatecholamines, okokuqala sinee-adrenergic receptors (norepinephrine kunye neadrenaline): Ezi zimbini ze-neurotransmitters zineempembelelo ezahlukeneyo, ezichazwa bubukho bezamkeli ezahlukeneyo, ezikuhlobo ngalunye lweseli idityaniswe kwiindlela ezahlukeneyo zokuhambisa.
Kwimisipha egudileyo inokuvelisa ukusasazeka ukuba ngaba abamkeli bayasebenza, kwaye baphumle ukuba bayasebenza? 2 Ii-receptors. Kwimithambo yegazi ivelisa i-vasoconstriction kunye ne-vasorelaxation.
Nangona kunjalo, okwahlukileyo kweenqanawa, kwimibhobho ye-bronchial ivelisa i-bronchodilation. Ngelixa ukwetyisa kugqithisa kwaye kubangela ukuphumla. Ngokukhawuleza ndi intliziyo inyusa ukubetha kwentliziyo kunye nokuqina kwayo; ukwandisa imveliso yentliziyo.
Ii-adrenergic receptors zinxulumene ngokuhambelana, kodwa zinabathunywa besibini abohlukileyo. Ngaba ii-receptors zahlukile? Y?; I-Epinephrine kunye ne-norepinephrine zi-agonists zazo zombini ii-receptors, kodwa ezi zinama-agonists kunye nabachasi. Umamkeli? inokuba ngu? 1 okanye? 2. I-1 ingaba ngu-A, B, okanye u-D.
Ezi zinto zintathu zahlukile kubachasi, indawo, ulwakhiwo kunye nendlela yokusebenza (adenylate cyclase). Kule meko, okubalulekileyo kukuba i-adenylate cyclase ibangela ifuthe elahlukileyo kwindawo nganye emzimbeni. I? banokuba ngu-1, 2 okanye 3. Bahlukile kubachasi, kunye neempawu. Kodwa zonke ezi-3 zivuselela i-adenylate cyclase.
Ukubaluleka ekusebenzeni kwemihla ngemihla komzimba womntu
Ezi neurotransmitters zimele ukubaluleka okukhulu kwizenzo zomzimba wethu, kuba zinemisebenzi emininzi. Bathatha inxaxheba kuzo zombini iindlela ze-neural kunye ne-endocrine.
Enye yezi mpembelelo yile bayenzayo kwinkqubo ye-nervous system abayilawulayo kukuhamba, ukuqonda, iimvakalelo, ukufunda kunye nenkumbulo. Ngokumalunga noxinzelelo, iikatekolines zidlala indima ebalulekileyo kwiimpendulo kuyo, zikhulula ezi zinto xa ufumana uxinzelelo lomzimba okanye lweemvakalelo.
Ngo-1990 abaphandi bagqiba kwelokuba kwinqanaba leeseli, ezi zinto zilungelelanisa imisebenzi ye-neuronal ngokuvula okanye ukuvala amajelo e-ion ngokwee-receptors ezichaphazelekayo.
Buqinisekiswa njani ubukho bayo?
Amanqanaba eCatecholamine anokuchongwa ngokufunda kunye nokuvavanya igazi kunye nomchamo. Ngapha koko, ii-catecholamines ziboshwe malunga ne-50% yeeproteni ezisegazini.
Xa ukungaphumeleli okanye ukwehla kwe-catecholamine neurotransmission kusenzeka, iingxaki ezithile ze-neurological kunye neuropsychiatric zenziwa. Enye yazo kukudakumba, okunxulunyaniswa amanqanaba asezantsi ezi zinto, ngokuchasene nexhala. Kwelinye icala, i-dopamine ibonakala ngathi idlala indima ebalulekileyo kwizifo ezinjengeParkinson's kunye ne-schizophrenia.
Okokugqibela, kubalulekile ukuqonda ukuba amanqanaba e-catecholamine anokuxhomekeka kuthi ukuba sithatha ukutya okuthile okunexabiso elifanelekileyo lezinto ezikhuthaza le neurotransmitter. Kukho ukutya okunobukho obuphezulu be-phenylalanine efana nenyama ebomvu, amaqanda, intlanzi, ubisi, ii-chickpeas, iilentile, amandongomane, njl.
Kwi-aspartame, esona siswiti sisetyenziswa kakhulu kushishino lokutya, imele ngaphezulu kwe-60% yentengiso yehlabathi kwezi zongezelelo zisetyenziswa kakhulu kwiziselo ezinencindi nakwimveliso yokutya, ikwafumaneka apho. Ngelixa i-tyrosine inokufumaneka kwitshizi.
Siziva njani?
Zombini ezi zinto zisebenza njengehomoni ezihambelanayo. Oku kuthetha ukuba bayalinganisa iziphumo zokungasebenzi kakuhle kwinkqubo yeemvakalelo enovelwano.
Ngendlela yokuba xa ezi zinto zikhutshelwa egazini, ukonyuka koxinzelelo lwegazi, ukukhululeka kwemisipha, kunye nokwanda kwenqanaba leswekile kunamava. Kananjalo ukukhawulezisa kwenqanaba lentliziyo kunye nokuphefumla. Oku kuchaza ukuba kutheni ii-catecholamines zibalulekile ekuphenduleni iimpendulo zokulwa okanye zokubaleka kuxinzelelo.
Ukukhutshwa kweCatecholamine
Ukuze kukhutshwe ii-catecholamines, kufuneka kukhutshwe i-acetylcholine. Olu khuko lunokwenzeka, umzekelo, xa sibona ingozi. I-Acetylcholine ingenisa i-adrenal medulla kwaye ivelise uthotho lweziganeko zeselula.
Xa i-adrenaline iphakama, ukwanda kwento ebizwa ngokuba sisivumelwano sentliziyo yenziwa. Ukongeza, ukubetha kwentliziyo kuyanda. Oku kubangela ukwanda konikezelo lweoksijini. Ngendlela efanayo, bonyusa izinga lokuphefumla. Ukongeza, ineziphumo ezinamandla zokuphumla.
Okokugqibela, kubalulekile ukuba siyazi ukuba isenza ukuba sisabele ngokukhawuleza kwisikhuthazo kwaye sifunde kwaye sikhumbule ngcono. Nangona kunjalo, amanqanaba aphezulu ezi zinto zinxulunyaniswa neengxaki zoxinzelelo. Ngelixa amanqanaba asezantsi edopamine ebonakala ngathi anempembelelo ekubonakala kokuphazamiseka kuqwalaselo, ubunzima bokufunda kunye noxinzelelo.