Ziziphi iip peptides ze-natriuretic?

Njengoko kwachazwa kule minyaka edlulileyo, ngaphandle kwemisebenzi ecacileyo intliziyo yenzayo indima yomzimba we-secretion yangaphakathi. Oku kwabangela ukuba inzala ingabikho kuphela phakathi kwababhali bezokwelapha, kodwa nakwabasebenzi. Ama-peptide ama-Natriuretic (NUP) ahlanganiswanga kuphela kwi-myocardium, kodwa nakwezinye iinxalenye zangaphakathi ezingazange zizichaze ngokwasemisebenzini ye-endocrine. Isigqibo esenziwe ngokubambisana senziwe ukuba kusetyenziswe ama-index of NUP egazini ukuxela ukuphuhliswa kweentsholongwane zentliziyo, kuba le ndlela yayiyinto encinci kwaye ingabonakaliyo isiguli.

Ukufumanisa umsebenzi we-endocrine yentliziyo

Ama-peptide angama Natriuretic atholakala kwiminyaka engama-80 ekhulwini lokugqibela, xa izazinzulu zibona ukudibanisa phakathi kokunyuka kwamagumbi entliziyo kunye nokuqina komchamo. Ababhali bokufumanisa okokuqala babecinga ukuba le nto ibonakalisa kwaye ayizange ibandakanye naluphi na ukubaluleka kuyo.

Kamva, xa i-pathomorphologists kunye neengcali zeengcali zithatha isifundo sale ngxaki, bafumanisa ukuba kwiiseli zezicubu ezenza i-atrium kukho iingxelo eziqulethe i-protein molecules. Kuye kwabonakaliswa ukuba i-extract kwi-atria yeenki ivelisa i-diuretic effect. Emva koko kwakunokwenzeka ukuhlukanisa i-peptide kwaye kuseke ukulandelelaniswa kwee-residu ze-amino acid ezenzayo.

Ngexesha elithile kamva, i-biochemist ihlukanise izixhobo ezintathu ezihlukeneyo (i-alpha, i-beta kunye ne-gamma) kule protheni, kungekhona nje kwindlela yokwenza iikhemikhali, kodwa nangokwemiphumo: i-alpha yayinamandla kunezinye ezimbini. Ngoku kwahlula:

I-NUP ye-Atrial (uhlobo A);
- NUP yengqondo (uhlobo B);
- urodilatin (uhlobo C).

I-biochemistry ye peptide ye-natriuretic

Zonke iip peptide ze-natriuretic zifana nesakhiwo kwaye zihluke kuphela kwii-radicals ze-nitrogen eziphelayo okanye kwi-athomu ye-carbon. Kuze kube ngoku, yonke ingqalelo i-chemists igxininiswe kwi-BUP uhlobo B, ekubeni inesimo esomeleleyo kwi-plasma yegazi, kwaye ivumela ukufumana iziphumo ezingakumbi. I-NUP yonyango idlala indima yomntu ochanekileyo wamanqanaba e-electrolyte yamanzi omzimba. Iveliswa kwi-myocardium kokubili kwimiqathango kunye nasemva kwemeko engapheliyo yentliziyo.

Kuboniswa ukuba umphambili weengqondo ze-NUP unama-residu angu-108 e-amino acid eyenziwe ngamaseli e-ventricle engasekhohlo. Xa i-molecule ikhululiwe kwi-cytoplasm, iyenziwa yi-enzyme furin, eyenza le protein ibe yindlela esebenzayo (i-32 amino acid e-108). I-Brain NUP ikhona egazini kwimizuzu engama-40 kuphela, emva koko iyancipha. Ukwanda kweprotheni kufakelwe ukunyuka kwoluhlu lweendonga ze-ventricles kunye ne-ischemia yentliziyo.

Ukupheliswa kwe-NPP kwiplasma kwenziwa ngeendlela ezimbini ezibalulekileyo:

- cleavage nge-enzymes i-lysosomal;
- proteolysis.

Indima ehamba phambili inikwe igalelo kwi-molecule ye-endopeptidase engathathi hlangothi, kodwa zombini iindlela zinegalelo ekupheliseni iipepptide ezibonakalayo.

Inkqubo yeReceptor

Yonke imiphumo yama-peptide angamahlwempu ayenzeka ngenxa yokusebenzisana kwabo kunye nama-receptors asebuchopho, imithana yegazi, imisipha, ithambo kunye nezicubu ze-adipose. Elinganayo kwiintlobo ezintathu ze-NPM, kukho iintlobo ezintathu ze-receptors-A, B kunye no-C. Kodwa ukuhanjiswa kwe "xanduva" akucaci ngokucacileyo:

- Thayipha i-receptors inxibelelwano ne-atrial kunye ne-NUP ye-cerebral;
Uhlobo lwe-B luphela kuphela kwi-urodilatin;
- I-receptors C inokubopha kuzo zonke iintlobo ezintathu zeamolekyuli.

Abamukeli bahluke ngokukodwa komnye nomnye. Iimpawu ze-A ne-B zenzelwe ukuzaliswa kwemiphumo ye-intracellular ye-peptide ye-natriuretic, kwaye abahlobo be-C receptors ziyimfuneko kwi-biodegradation yamamolekyuli eeprotheni. Kukho ukucinga ukuba umphumo weengqondo ze-NUP ayifumanekanga kuphela ngohlobo lwe-receptors, kodwa nakwezinye iinjongo ezinomdla ezithathayo kumlinganiselo we-guanosine monophosphate.

Inani elona likhulu lokufumana uhlobo lwe-C lufunyenwe kwizicubu zengqondo, izigulane ze-adrenal, izintso neempahla. Xa i-molecule ye-NPM ibophelela kummkeli we-C, ixhaswa yiseli kwaye ifakwe, kunye ne-receptor yamahhala ibuyiselwa kwi-membrane.

I-Physiology ye peptide ye-natriuretic

I-Brain kunye nama-peptides angama-atriyriyali angama-atrial ayazibona iziphumo zabo ngokusebenzisa inkqubo yezinto ezithintekayo zomzimba. Kodwa zonke ekugqibeleni zikhokelela kwelinye injongo - ukunciphisa ukulayisha kuqala kwintliziyo. I-NUP ithinta i-cardiovascular, i-endocrine, inkqubo ye-nervous ne-central.

Ekubeni la malekyuli anamaqabane awamkeleyo ahlukeneyo, kunzima ukuhlula imiphumo ethile yeentlobo ezithile ze-NPM zibe nenkqubo ethile. Ukongeza, isenzo se peptide asixhomekanga kakhulu kumhlobo walo njengendawo yokufumana i-receptor receptor.

I-peptide yamatriuretic ye-Atrial ibhekisela kuma-peptide e-vasoactive, oko kukuthi, ichaphazela ngqo ububanzi beempahla. Kodwa ukongeza, iyakwazi ukukhuthaza ukuveliswa kwe-nitric oxide, ekwabangela ukuba kwandiswe imilambo yegazi. Uhlobo lwe-N A kunye no-B lunamandla anjalo kunye nomphumo wokulawula kuzo zonke iindidi zeenqanawa, kunye nohlobo lwe-C lufikelela kuphela kwimifuno.

Kungekudala, uluvo luboniswa ukuba i-NPM ingabonakali nje kuphela njenge-vasodilator, kodwa ngokuyinhloko njengomchasana we-vasoconstrictor. Ukongezelela, kukho iingcaphephe ezibonisa ukuba ii-peptides ze-natriuretic zichaphazela ukusasazwa kwimizi ngaphakathi nangaphandle kwenethiwekhi ye-capillary.

Iimpembelelo zamaRenal of Peptide yase Natriuretic

Ngokuphathelele i-peptide ye-natriuretic, ungatsho ukuba yi-diuresis ekhuthazayo. Okokuqala, thayipha i-NP yenza ngcono ukuhamba kwegazi kunye nokunyusa uxinzelelo kwiinqanawa ze-glomerular. Oku, kwandisa ukuhlanjululwa kwe-glomerular. Ngexesha elifanayo, uhlobo lwe-NPC uhlobo C luyakhuthaza ukupheliswa kwe-ion ion, kwaye oku kukhokelela ekulahlekelweni kwamanzi.

Nangona kunjalo, akukho tshintsho oluphawulekayo kwingcinezelo yenkqubo, nangona izinga leep peptides linyuka ngamaxesha amaninzi. Bonke oososayensi bayavuma ukuba iimpembelelo ze-peptides ezinomdla ziba neentso eziyimfuneko ukulungisa ukulinganisela kwamanzi-electrolyte kwi-pathologies engapheliyo ye-cardiovascular system.

Impembelelo kwinkqubo yesantya ephakathi

Ingqondo yengqondo ye-peptide, njenge-annrial, ayikwazi ukungena kwi-barrier brain-barrier. Ngako oko, zichaphazela izakhiwo zesimiso se-nervous located outside it. Kodwa ngelo xesha inxalenye ethile ye-NUP ifihliwe yi-envelopes yengqondo kunye nezinye iinjongo zobomi.

Iziphumo eziphambili zeeproptides ezihamba ngamanzi ziyakuthi zomeleze utshintsho lwe-peripheral ekhoyo. Ngoko, umzekelo, kunye nokunciphisa ukulayishwa kwangaphambili entliziyweni, umzimba unciphisa isidingo sawo samanzi kunye nosawoti wamaminerali, kwaye utshintshe ithoni yenkqubo ye-neon autonomic kwi-parasympathetic inxenye.

Amakishi eLebhu

Ingcamango yokuthatha i-peptide ye-natriuretic ukwenzela ukuhlalutya ngexesha leengxaki ze-cardiovascular disorders zenzeka ekuqaleni kwawo-1990. Emva kweminyaka elishumi, iimpapasho zokuqala zavela kunye neziphumo zophando kule ndawo. Kwaxelwa ukuba uhlobo lweB B lukwazisa ekuhloleni ubunzima bokuphelelwa yintliziyo nokuchazwa kwesi sifo.

Umxholo weprotheni unqunywe kwigazi eligcwele igazi elixutywe ne-ethylenediaminetetraacetic acid, okanye ngohlalutyo lwe-immunochemical. Ngokuqhelekileyo, izinga le-NPC akufanele lidlule i-100 ng / ml. Ukongezelela, kunokwenzeka ukugqiba umgangatho we-NPC ngaphambili ngomgaqo we-electrochemiluminescent. Imveliso yasekhaya, engenazo iintlobo ezahlukeneyo, isebenzisa i-enzyme immunoassay njengesixhobo sokuphela kwendawo yokumisela inani lempahla kwi-serum yegazi.

Inkcazo yokukhubazeka kwenhliziyo

I-peptide ye-sodium-urethritic (ngokuqhelekileyo - ukuya kwi-100 ng / ml) okwangoku iyona ethandwa kakhulu kwaye ibona amanqaku amaninzi okwenza i-heart muscle ididisction. Izifundo zokuqala zeep peptide zahlanganiswa nobunzima bokuhlula ukuhluleka kokujikeleza kwegazi kunye nesifo esingapheliyo sesiphene. Ekubeni iimpawu zekliniki zafana, uvavanyo lukuncede ukuchonga imbangela yesifo kunye nokuqikelela ukuphuhliswa kokuqhubeka kwesi sifo.

I-pathology yesibini, ehlolwe ngolu hlobo, yayisifo se-heart coronary. Ababhali bezifundo bayavuma ukuba ukuzimisela kwinqanaba le-NPM kusiza ukuseka ukufa okuqikelelwayo okanye izinga lokuphindaphinda kwisigulane. Ukongezelela, ukubeka iliso kwinqanaba le-NUP ngumakishi wokusebenza kwonyango.

Okwangoku, izinga le-NUP lithethwa kwizigulane ezinomzimba, uxinzelelo lwegazi, i-stenosis yeenqanawa ezinkulu kunye nezinye izifo ezijikelezayo.

Isicelo kwi-cardiosurgery

Ngumkhosi, kwafunyaniswa ukuba izinga leepriptidi ye-acriartic acid egazini lingaqwalaselwa njengendlela yokubonisa ubunzima besimo kunye nomsebenzi we-ventricle ekhohlo kwizigulane ngaphambi nangemva kwemisebenzi yentliziyo.

Ukufunda kwesi siqalo kwaqala ngo-1993, kodwa kwafikelela kwisikhulu esikhulu kuphela kuma-2000. Kwafunyaniswa ukuba ukuhla okubukhali kwinani le-NUP kwigazi le-peripheral, ukuba ngaphambi kokuba le nqanaba lihlale liphakanyisiwe, kubonisa ukuba umsebenzi we-myocardial ubuyiselwe kwaye umsebenzi uphumelele. Ukuba kwakungekho nciphisa kwi-NUP, isiguli safa nge-100%. Intsebenziswano phakathi kweminyaka yobudala, isondo kunye nep peptide level ayibonakalwanga, ngoko ke, le ncwadana iphela yonke iindidi zezigulane.

Ukuxhamla kwangaphambili

Ngaphambi kokungenelela kwintliziyo, i-peptide ye-natriuretic iphakanyisiwe. Emva koko, ukuba kwakungenjalo, kwakungekho mfuneko yonyango nokuba. Umgangatho ophakamileyo we-NPM kwizigulane ngaphambi kokuba unyango luyinto engathandekiyo echaphazela kakhulu ukugxekwa emva kokuhlinzwa.

Ekubeni iqela elikhethiweyo kwisifundo alininzi, iziphumo zadibaniswa. Ngakolunye uhlangothi, ukuzimisela kwinqanaba le-NUP ngaphambi nangemva kokusebenza kwavumela oogqirha ukuba baxelele ukuba yiyiphi imithi kunye nenkxaso yokuxhasa intliziyo eyayiyodinga ide ibuyiswe imisebenzi yayo. Kwakhona kwaqaphelwa ukuba inani elongeziweyo lohlobo B BCD luyi-harbinger ye-fibrillation ye-atrial kwisithuba se-postoperative.