Basa reRenin Enzyme muRopa Regulation Regulation
Kumanikidzwa kweropa chinhu chakakosha chinosarudza mashandiro akanaka ehurongwa hweropa. Kana kumanikidzwa kweropa kwakaderera zvakanyanya, kupihwa kweokisijeni nezvinovaka muviri kunhengo dzinokosha kunogona kukanganiswa. Kusiyana neizvi, kana kwakakwira zvakanyanya uye kukaramba kuripo kwenguva yakareba, kunogona kukuvadza mitsipa yeropa uye kuwedzera njodzi yechirwere chemwoyo, sitiroko, uye matambudziko eitsvo. Muviri une nzira dzakasiyana dzekuchengetedza kumanikidzwa kweropa kwakasimba, imwe yacho iri kuburikidza nekushanda kweenzyme renin. Renin chikamu chakakosha che renin–angiotensin–aldosterone system (RAAS), nhevedzano yemaitiro emahormone anodzora kumanikidzwa kweropa uye kuenzana kwemvura mumuviri. Chinyorwa chino chinokurukura mashandiro eenzyme renin, mashandiro ayo, zvinhu zvinoipesvedzera, uye kukosha kwayo mukurapa.
Chii chinonzi renin?
Renin iprotease (enzyme inopwanya mapuroteni) inogadzirwa zvakanyanya nemasero ejuxtaglomerular ari muitsvo. Masero aya ari mumadziro e afferent arteriole, tsinga diki yeropa inotakura ropa kuenda ku glomerulus (itsvo's filtering unit). Renin haishande yoga; inotanga "chain reaction" inoguma nekuumbwa kwemahormone anogona kuwedzera BP. Nemamwe mashoko, renin ndiyo yekutanga kune imwe yenzira dzinonyanya kukosha dzemuviri dzinodzora BP.
Renin inoburitswa riini?
Kuburitswa kwerenin kunoitika kana muviri ukaona mamiriro ezvinhu anokonzera kudzikira kweropa (kuyerera) kana kudzikira kwehuwandu hwemvura. Kazhinji, renin inowedzera kana:
1. Kuderera kwesimba remvura inoyerera muitsvo
Semuenzaniso, kana paine kushaya mvura mumuviri, kubuda ropa, kana kuderera kweBP kamwe kamwe, itsvo dzinoti izvi zviratidzo zvekukurumidzira kuti ropa rirambe richiyerera.
2. Kuderera kwehuwandu hweSodium chloride (NaCl) mu distal tubule
Sensor iyi inoitwa nemasero e macula densa (chikamu chejuxtaglomerular apparatus). Kana NaCl yakaderera ikasvika pa macula densa, zvinowanzo ratidza kudzikira kwekusefa kweitsvo kana kudzikira kwehuwandu hwemvura mumuviri, zvichikonzera kuburitswa kwe renin.
3. Kuwedzera kushanda kwehurongwa hwetsinga dzinobatsira
Munguva yekushushikana, kurwadziwa, kuchinja kwenzvimbo (semuenzaniso kumira kamwe kamwe), kana kuvhunduka, sisitimu yetsitsi inovhurwa uye inokurudzira ma β1 receptors pamasero ejuxtaglomerular kuti abudise renin.
Nzira nhatu idzi dzinoratidza kuti renin inoshanda semhinduro inochinja-chinja yemuviri kuti irambe iine BP uye ropa rinoenda kunhengo dzemuviri.
Maitiro ekuita kwe renin muRAAS
Basa raRenin mukudzora BP rinoitika kuburikidza neRAAS. Kurongeka kwemaitiro kunogona kutsanangurwa seizvi:
1. Renin inoputsa angiotensinogen kuita angiotensin I
Angiotensinogen ipuroteni inogadzirwa nechiropa uye inotenderera muropa. Renin inocheka angiotensinogen kuita angiotensin I, iyo isingashande zvakanyanya.
2. Angiotensin I inoshandurwa kuita angiotensin II neACE
Angiotensin-converting enzyme (ACE) inowanikwa zvakanyanya mu endothelium yetsinga dzeropa, kunyanya mumapapu. ACE inoshandura angiotensin I kuita angiotensin II, molekyuru inoshanda ine simba guru mukusimudzira BP.
3. Angiotensin II inowedzera BP kuburikidza nenzira dzakasiyana-siyana.
Angiotensin II inoshanda se "pakeji yakazara" yekuwedzera BP, kusanganisira ne:
– Kutetepa kwetsinga dzeropa (vasoconstriction): Mitsinga dzeropa dzinotetepa zvekuti kudzivirira kweropa kunowedzera, uye BP inokwira.
– Inokurudzira kuburitswa kwealdosterone kubva muadrenal glands: Aldosterone inowedzera kutorwazve kwesodium nemvura muitsvo, nokudaro ichiwedzera huwandu hweropa.
– Inokurudzira kuburitswa kweADH (vasopressin): ADH inowedzera kutorwazve kwemvura muitsvo, zvichiita kuti huwandu hwemvura huwedzere.
– Nyota yakawanda: Muviri unokurudzirwa kunwa mvura yakawanda, zvichibatsira kuwedzera huwandu hwemvura.
– Inokanganisa tsinga dzinonzwa tsitsi: Angiotensin II inogona kusimbisa mashandiro etsinga dzinonzwa tsitsi, izvo zvinowedzerawo BP.
Saka, renin inoshanda se "start switch" iyo inomutsa ketani yekuchinja kusvika BP ne blood blood vhoriyamu zvichizowedzera.
Renin uye chiyero chemvura uye electrolyte
Kudzora kumanikidzwa kweropa hakuparadzaniswi nekudzora kwemvura uye electrolyte. Munyaya iyi, renin, kuburikidza neRAAS, inoita basa guru mukuchengetedza huwandu hwesodium nemvura. Zvakakosha kuyeuka kuti sodium ine simba re "kuchengetedza mvura" mumuviri. Kana aldosterone ikawedzera, itsvo dzinochengeta sodium yakawanda; mvura inochengetwawo, zvichiwedzera huwandu hweropa. Kuwedzera uku kwehuwandu hweropa pakupedzisira kunobatsira mukuwedzera kweBP.
Zvisinei, nzira iyi inofanira kuenzaniswa. Kana RAAS ikashanda zvakanyanya, kuchengetwa kwe sodium yakawanda nemvura kunogona kukonzera kuzvimba (kuzvimba) uye kuwedzera basa remoyo. Mune zvimwe zvirwere, kushanda kweRAAS chinhu chakakosha mukufambira mberi kwechirwere.
Maitiro ekupa mhinduro kuti usanyanya kuidarika
Muviri une nzira yekubatsira kudzivirira kuwedzera kweropa kusingadzoreki. Kana BP neitsvo zvikawedzera, kana kana sodium nefluid zvikakwana, kuburitswa kwerenin kunoderera. Angiotensin II inogonawo kupa mhinduro dzisina kunaka, zvichidzivisa kuburitswa kwerenin zvakanyanya.
Pamusoro pezvo, kune mahormone anoshanda zvinopesana neRAAS, akadai seANP (atrial natriuretic peptide), iyo mwoyo unoburitsa kana huwandu hweropa hwakawandisa. ANP inokurudzira kuburitswa kwesodium nemvura kuburikidza neitsvo, nokudaro ichideredza huwandu hweropa nekumanikidzwa, ukuwo ichidzvinyirira kushanda kweRAAS.
Zvinhu zvinokanganisa mazinga e renin
Mazinga eRenin anogona kusiyana zvichienderana nevanhu nemamiriro ezvinhu. Zvimwe zvinhu zvinogona kuwedzera renin zvinosanganisira:
- Kushaya mvura mumuviri kana kushaikwa kwemvura mumuviri
- Kudya kushoma kwemunyu
- Kubuda ropa
– Kumira kwenguva refu (kuchinja chinzvimbo kubva pakureva nhema kuenda pakumira)
– Kuoma kwetsinga dzeropa dzeitsvo (kutetepa kwetsinga dzeropa dzeitsvo)
- Kushanda kwetsitsi kwakanyanya
Kusiyana neizvi, renin inogona kuderera mumamiriro ezvinhu akadai se:
- Kudya munyu wakawanda
- Zvimwe zvirwere zvine aldosterone yakawandisa (primary hyperaldosteronism)
- Kuwedzera kwehuwandu hweropa
- Kushandisa mimwe mishonga inodzvinyirira RAAS
Kukosha kwekiriniki: sei renin ichikosha muBP?
Renin ine basa guru muzviitiko zvakawanda zveBP (BP yakakwira), kunyanya izvo zvine chekuita neitsvo kana mahormone. Semuenzaniso, mu stenosis yetsinga dzeitsvo, itsvo dzinowana kuyerera kweropa kwakaderera, zvichiita kuti dzifunge kuti muviri hauna kusimba. Renin inowedzera, RAAS inoshanda, uye BP inokwira. Iyi mamiriro muenzaniso wekuti kusashanda zvakanaka kweitsvo munharaunda kunogona sei kukonzera BP.
Mukurapa, bvunzo dzeplasma renin nealdosterone dzinogona kubatsira vanachiremba kuona kana BP iri kukonzerwa nezvimwe zvirwere zvemahormone. Chiyero chealdosterone-renin chinowanzo shandiswa kuongorora kana paine chirwere cheprimary hyperaldosteronism.
Renin sechinangwa chekurapa nemishonga
Nekuti RAAS yakakosha zvikuru mukudzora BP, mishonga yakawanda yekuderedza BP inonyanya kunangana neiyi nzira, yakaita se:
- ACE inhibitor (inodzivirira kuumbwa kweangiotensin II)
– ARB (angiotensin receptor blocker) (inodzivirira kushanda kweangiotensin II pamareceptor ayo)
- Aldosterone antagonist (inodzivirira mhedzisiro yealdosterone)
- Mishonga inodzivirira renin zvakananga (semuenzaniso aliskiren, iyo inodzivisa danho rekutanga, basa re renin)
Mishonga iyi haingoderedzi BP chete, asi inowanzoshandiswawo kudzivirira nhengo dzemuviri dzakadai semwoyo neitsvo mune mamwe mamiriro ezvinhu.
Mhedziso
Enzyme renin chinhu chakakosha mukudzora BP nekuti ndiyo inotanga kuita kuti system ye renin-angiotensin-aldosterone ishande. Renin inoburitswa kunyanya kana muviri wawana kuderera kweropa, sodium yakaderera mu distal tubule, kana kuwedzera kwesimba re sympathetic. Kuburikidza nekuumbwa kwe angiotensin II uye kuwedzera kwe aldosterone ne ADH, RAAS inokurudzira vasoconstriction uye sodium-water retention, zvichizowedzera BP uye kuchengetedza kugadzikana kweropa. Kuenzana kwe renin kwakakosha: mwero wakaderera kana wakakwira zvakanyanya kunogona kukonzera matambudziko eBP. Naizvozvo, renin nenzira yeRAAS zvakakosha pakunzwisisa BP uye zvinangwa zvikuru zvekurapa kwakawanda kwemazuva ano.
