Imicu yePurkinje enhliziyweni

Inhliziyo yethu iyisiphako esinendlela yokwehlukanisa ngokuphelele. Ngaphakathi kuyisimiso esiyinkimbinkimbi samaseli athile (ama-pacemaker), anesistimu yezinga eliphezulu lokuqapha umsebenzi. Kuhlanganisa, phakathi kwezinye izinto, ama-Purkinje fibers. Zitholakala engxenyeni ye-carbohydrate ye-ventricles futhi zibhekene nokuqedwa kwe-synchronous.

I-anatomy jikelele yenqubo yokuqhuba

Uhlelo lokuqhuba inhliziyo luhlukaniswe ngezigaba ezine ngama-anatomists. Ingxenye yokuqala ihlanganisa node ye-sinus (sinoatrial) node. Kuyinto inhlanganisela yezinqwaba ezintathu zamangqamuzana ezikhiqiza ukuvuthwa ngezikhathi ezingamatshumi ayisishiyagalombili kuya kwekhulu namashumi amabili ngomzuzu. Ukulinganisa kwenhliziyo okunjalo kuphazamisa ukugcina ukujikeleza kwegazi okwanele emzimbeni, ukugcwalisa oksijini kanye nesilinganiso semethamo.

Uma ngesizathu esithile i-pacemaker yokuqala ayikwazi ukwenza imisebenzi yayo, i-node atrioventricular (atrioventricular) node ingena kulolu cala. Itholakala emngceleni wamakamelo enhliziyo ku-septum ephakathi. Lokhu kuqoqwa kwamaseli kusetha imvamisa yezinsizakalo emkhakheni wezintambo ezingamashumi ayisithupha kuya kweziyisishiyagalolunye futhi kubhekwa njengomshayeli wesigqi sesibili.

Izinga elilandelayo lendlela yokuqhuba iyisigxobo seZakhe kanye nezintambo zePutkinje. Zitholakala ku-septum yangasese futhi zibopha isiphetho senhliziyo. Lokhu kwenza kube lula ukusabalalisa imishanguzo kagesi eduze kwe-myocardium ye-ventricular. Isivinini sesizukulwane sihluka kusuka izikhathi ezingamashumi amane kuya kwamashumi ayisithupha ngomzuzu.

Igazi

Izingxenye zesistimu yokuqhuba, ezise-atria, zithola izakhi ezivela emithonjeni eyodwa, ngokwahlukana nayo yonke imotocardium. I-node i-sinoatrial iyondla imithwalo emincane eyodwa noma emibili edlula ebukhulu bezindonga zenhliziyo. Ubungqayizivele bukhona phambi kwe-artery enkulu engavumelani edlula phakathi node. Lona igatsha le- artery coronary efanele . Futhi, inikeza amagatsha amancane amancane awenza inethiwekhi enamandla kakhulu ye-arterial-venous kule ndawo yezicubu zomzimba.

Inqwaba ye-Giesa ne-Purkinje fibers nayo yondliwa kusuka emagatsheni omzimba we-coronary (i-artery interventricular) noma ngqo kuyo. Kwezinye izimo, igazi lingangena lezi zakhiwo kusukela emvilophini yomthambo. Napha futhi, inethiwekhi encane yama-capillary, okwakhiwa kakhulu ama-cardiomyocytes.

Amaseli ohlobo lokuqala

Umehluko emangqamuzaneni afaka isimiso sokuziphatha ngenxa yokuthi enza imisebenzi ehlukile. Kunezinhlobo ezintathu eziyinhloko zamaseli.

I-pacemakers ehamba phambili yi-P-amaseli noma amaseli ohlobo lokuqala. Ngokwemvelo, lawa maseli amangqamuzana amancane ane-nucleus enkulu nezinqubo eziningi eside ezihlangene. Amangqamuzana amakhelwane angomakhelwane abhekwa njengamaqoqo, ahlangene nengqamuzana evamile ye-basal.

Kuhlelwe izingongolo ze-myofibril ukuze zikhiqize iziphazamiso ngaphakathi kwendawo yangaphakathi yama-P. Lezi zakhi azihlali ngaphansi kwengxenye yendawo yonke ye-cytoplasmic. Ezinye i-organelles zikhona ngezikhathi ezithile ngaphakathi kweseli futhi zingaphansi kwe-cardiomyocytes evamile. Futhi-ke, amashubhu e-cytoskeleton, ngakolunye uhlangothi, aphethwe kakhulu futhi asekela ukuma kwabaqhubi bemigqi.

Kulezi zinqamuzana kukhona i-node-atrial node, kodwa zonke ezinye izakhi, kuhlanganise ne-Purkinje fibers (i-histology yakhe izochazwa ngezansi), ibe nesakhiwo esihlukile.

Amaseli ohlobo lwesibili

Babizwa nangokuthi abashayeli besigqi esiphezulu noma esivamile. Ububunjwa obungalungile, bufushane kune-cardiomyocytes evamile, kodwa bunokuqina obukhulu, aqukethe ama-cores amabili, futhi udonga lweseli lunemifino ejulile. I-Organelles kulawa maseli inkulu kunaleyo ye-cytoplasm yamaseli e-P.

Izintambo zokuqhaqha zandiswa nge-axis ende yeseli. Zinyene futhi zinama-sarcomeres amaningi. Lokhu kuvumela ukuba babe abashayeli besigqi sesibili. Lawa maseli asezindaweni ze-atrioventricular, futhi ama-fasciculus nama-Purkinje fibers kuma-micro amalungiselelo amelelwa ngamaseli ohlobo lwesithathu.

Amaseli wesigaba sesithathu

Abahlengikazi baye baqaphela izinhlobo eziningana zamaseli ezingxenyeni zokugcina zenqubo yokuqhuba inhliziyo. Ngokwezigaba ezibhekwe lapha, amaseli ohlobo lwesithathu azoba nesakhiwo esifanayo nalabo abenza ama-Purkinje fibers enhliziyweni. Ziningi kakhulu, uma ziqhathaniswa nezinye izigqi zomculo, zide futhi zibanzi. Ubukhulu be-myofibrils abufani kuzo zonke izindawo ze-fiber, kodwa inani lazo zonke izakhi ezivumelwano zingaphezu kwe-cardiomyocyte evamile.

Manje singakwazi ukuqhathanisa amaseli ohlobo lwesithathu nalabo abenza ama-Purkinje fibers. I-Histology (ukulungiswa okutholakala ezicukwaneni ezingxenyeni zenhliziyo) yalezi zakhi kuhluke kakhulu. I-nucleus ine-shape engama-rectangular, futhi izinsimbi ezihlanganiswayo zenziwe zibe buthakathaka, zinamagatsha amaningi futhi zixhunyane. Ngaphezu kwalokho, azikho emaceleni ngokucacile ubude bendawo futhi zikhona ngezikhathi eziningi. Inani elincanyana le-organelles, elitholakala eduze kwama-myofibril.

Ukungafani emvuthweni we-pulses okukhiqizwayo kanye nejubane layo kudinga indlela ephikisana ngayo ye-phylogenetically yokuvumelanisa inqubo yokweqa kuzo zonke izingxenye zenhliziyo.

Ukwahlukana kwakhe ngokwemvelo kwesistimu yokuqhuba kusuka e-cardiomyocytes

Amaseli ohlobo lwesibili nolwesithathu anesisindo esikhulu se-glycogen kanye nemetabolites ayo kune-cardiomyocytes evamile. Lesi sici senzelwe ukuhlinzeka ngezinga elanele lemisebenzi yepulasitiki nokumboza izidingo zamaseli ezakhiweni. Ama-enzymes aphethwe yi-glycolysis kanye ne-glycogen synthesis zisebenza kakhulu emaqenjini wesistimu yokuqhuba. Emaseli asebenzayo enhliziyweni kukhona isithombe esingehlukile. Ngenxa yalesi sici, ukunciphisa ukuthuthwa kwe-oksijeni kulula ukubekezelela izinhliziyo zokugunda, okuhlanganisa ama-Purkinje fibers. Ukulungiswa kwesistimu yokuziphatha ngemuva kokwelashwa ngezinto ezinomsebenzi kubonisa umsebenzi ophezulu owenziwe nge-cholinesterase kanye ne-enzymes lysosomal.