Ngekhulu le-19, usosayensi osemusha waseJalimane wathola i-heterogeneity yezicubu ze-pancreatic. Amaseli abehluke kunenqwaba atholakala emaqenjini amancane, ama-islets. Amaqembu amaseli kamuva aqanjwa ngegama le-pathologist - izikebhe zeLangerhans (OL).
Isabelo sabo esisevolumu yezicubu eseqile asikho ngaphezu kwe-1-2%, noma kunjalo, le ngxenye encane ye-gland yenza umsebenzi wayo ehlukile kokugaya.
Ukuchithwa kweziqhingi zeLangerhans
Iningi lamaseli e-pancreatic (pancreas) akhiqiza ama-enzyme wokugaya. Umsebenzi wamaqoqo esiqhingi uhlukile - ahlanganisa ama-hormone, ngenxa yalokho abhekiselwa ohlelweni lwe-endocrine.
Ngakho-ke, i-pancreas iyingxenye yezinhlelo ezimbili eziyinhloko zomzimba - ukugaya kanye ne-endocrine. Iziqhingi zingama-microorganisms akhiqiza izinhlobo ezi-5 zama-hormone.
Iningi lamaqembu e-pancreatic atholakala engxenyeni ye-pancreas, yize isiphithiphithi, i-mosaic inclusions ibamba yonke izicubu ze-exocrine.
Ama-OL abhekene nokulawula i-carbohydrate metabolism futhi asekele umsebenzi wezinye izitho ze-endocrine.
Isakhiwo esingokomlando
Isiqhingi ngasinye siyinto esebenza ngokuzimela. Ngokubambisana bakha i-archipelago eyinkimbinkimbi eyakhiwe ngamaseli ngamanye kanye nokwakheka okukhulu. Ubukhulu bawo buhlukahluka kakhulu - kusuka kuseli elilodwa le-endocrine kuya esiqhingini esikhulu esivuthiwe, esikhulu (> 100 μm).
Emaqenjini e-pancreatic, uhlu lwamakhosi wokuhlelwa kwamaseli, izinhlobo zawo ezi-5, lwakhiwe, wonke afeza indima yawo. Isiqhingi ngasinye sizungezwe izicubu ezithintekayo, sinezigaba lapho ama-capillaries etholakala khona.
Maphakathi namaqembu amangqamuzana we-beta, ngasemaphethelweni wezakhiwo - amaseli we-alpha ne-delta. Lapho sikhulu ubukhulu be-islet, amaseli aphathekayo aqukethe.
Iziqhingi azinawo ama-ducts, ama-hormone akhiqizwayo akhululwa ngohlelo lwe-capillary.
Izinhlobo zezitokisi
Amaqembu ahlukahlukene amaseli akhiqiza uhlobo lwawo lwamahomoni, alawula ukugaya, i-lipid ne-carbohydrate metabolism.
- Amaseli we-Alfa. Leli qembu le-OL litholakala emaphethelweni esiqhingi; umthamo wazo ungama-15-20% kasayizi ophelele. Bahlanganisa i-glucagon, i-hormone elawula inani likashukela egazini.
- Amaseli weBeta. Kuqoqwe maphakathi neziqhingi futhi kwenza iningi lawo, ama-60-80%. Bahlanganisa i-insulin, cishe i-2 mg ngosuku.
- Amaseli eDelta. Banesibopho sokukhiqiza i-somatostatin, ukusuka ku-3 kuye ku-10% wabo.
- Amaseli e-Epsilon. Inani lesisindo selonke alikho ngaphezulu kwe-1%. Umkhiqizo wabo yi-ghrelin.
- Amaseli we-PP. I-hormone pancreatic polypeptide ikhiqizwa yile ngxenye ye-OL. Kufika ku-5% weziqhingi.
Umsebenzi weHormonal
Indima yama-pancreas amakhulu.
Izinto ezisebenzayo ezakhiwe eziqhingini ezincane zilethwa ezithweni ngokugeleza kwegazi futhi zilawule i-carbohydrate metabolism:
- Umgomo oyinhloko we-insulin ukunciphisa ushukela wegazi. Ikhulisa ukumuncwa kwe-glucose ngama-membranes weseli, isheshise i-oxidation yayo futhi isize ukugcina i-glycogen. Ukulimala kwe-hormone engasebenzi kahle kuholela ekuthuthukisweni kwesifo sikashukela sohlobo 1. Kulokhu, ukuhlolwa kwegazi kukhombisa ukuba khona kwama-antibodies kumaseli e-veta. Uhlobo lwesifo sikashukela sohlobo 2 luba khona lapho ukuzwela kwezicubu kwe-insulin kuncipha.
- I-Glucagon yenza umsebenzi ophambene nayo - yandisa amazinga kashukela, ilawula ukukhiqizwa kwe-glucose esibindini, futhi isheshise ukuqhekeka kwama-lipids. Ama-hormone amabili, ahlanganisa isenzo somunye nomunye, avumelanise okuqukethwe kwe-glucose - into eqinisekisa umsebenzi obalulekile womzimba ezingeni lamaselula.
- I-Somatostatin ibambezela isenzo sama-hormone amaningi. Kulokhu, kukhona ukwehla kwezinga lokufakwa ushukela ekudleni, ukuncipha kokuhlanganiswa kwama-enzymes wokugaya ukudla, kanye nokwehla kwesilinganiso seglucagon.
- I-pancreatic polypeptide inciphisa inani lama-enzyme, inciphisa ukuphuma kwe-bile ne-bilirubin. Kukholelwa ukuthi kumisa ukuhamba kwama-enzyme wokugaya, ukuwonga kuze kube isidlo esilandelayo.
- IGhrelin ibhekwa njenge-hormone yendlala noma yokuhlanya. Ukukhiqizwa kwayo kunikeza umzimba uphawu lokulala.
Inani lama-hormone akhiqizwayo kuncike kushukela okutholwe ekudleni kanye nezinga le-oxidation yalo. Ngokwenyuka kwesilinganiso sayo, ukukhiqizwa kwe-insulin kuyenyuka. I-Synthesis iqala ekuqoqweni kwe-5.5 mmol / L ku-plasma yegazi.
Akukhona ukudla kuphela okungadambisa ukukhiqizwa kwe-insulin. Kumuntu ophile kahle, ukugxilisa okukhulu kakhulu kuyaphawulwa ngesikhathi sokucindezelwa okunamandla komzimba nokucindezela.
Ingxenye ye-pocreas ye-pancreas ikhiqiza ama-hormone anomthelela wokunquma kuwo wonke umzimba. Izinguquko ze-pathological ku-OL zingaphazamisa umsebenzi wazo zonke izitho zomzimba.
Ividiyo emayelana nemisebenzi ye-insulin emzimbeni womuntu:
Ukulimazeka kuma-pancreas e-endocrine kanye nokwelashwa kwawo
Imbangela yesilonda se-OL ingaba ukwanda kofuzo, ukutheleleka kanye nobuthi, izifo zokuvuvukala, izinkinga zokuzivikela komzimba.
Ngenxa yalokhu, kunqamuka noma ukuncipha okukhulu kokukhiqizwa kwama-hormone ngamaseli e-islet ahlukene.
Ngenxa yalokhu, lokhu okulandelayo kungahle kube:
- Thayipha isifo sikashukela sokuqala. Kubonakaliswa ukungabikho noma ukuntuleka kwe-insulin.
- Thayipha isifo sikashukela sesi-2. Kunqunywa ukungakwazi komzimba ukusebenzisa i-hormone ekhiqizwayo.
- Isifo sikashukela sokukhulelwa sikhula ngesikhathi sokukhulelwa.
- Ezinye izinhlobo zesifo sikashukela mellitus (MODY).
- Ama-Neuroendocrine tumors.
Izimiso eziyisisekelo zokwelashwa kohlobo lwe-1 yesifo sikashukela ukungeniswa kwe-insulin emzimbeni, ukukhiqizwa kwako kuyalimaza noma kuncishiswe. Izinhlobo ezimbili ze-insulin zisetshenzisiwe - zishesha futhi zisebenza isikhathi eside. Izinhlobo zokugcina zilingisa ukukhiqizwa kwe-pancreatic hormone.
Isifo sikashukela sohlobo 2 sidinga ukudla okuqinile, ukuvivinya umzimba ngokulinganiselayo, nemithi yokwandisa ushukela.
Izehlakalo zesifo sikashukela ziyanda emhlabeni wonke; sekubizwa ngokuthi inhlupho yekhulu lama-21. Ngakho-ke, izikhungo zokucwaninga ngezokwelapha zifuna izindlela zokubhekana nezifo zeziqithi zaseLangerhans.
Izinqubo kumanyikwe ziqala ngokushesha futhi kuholele ekufeni kwezichibi, okumele zixube ama-hormone.
Eminyakeni yamuva, kuye kwaziwa:
- amaseli we-stem afakelwe kuma-pancreatic izicubu aqala kahle futhi ayakwazi ukukhiqiza ama-hormone ngokuzayo, ngoba aqala ukusebenza njengamaseli we-beta;
- I-OL ikhiqiza ama-hormone amaningi uma ingxenye yezicubu ze-pancreas isuswa.
Lokhu kuvumela iziguli ukuba zilahle ukudla njalo kwezidakamizwa, ukudla okuqinile futhi zibuyele endleleni ejwayelekile. Inkinga ihlala namasosha omzimba, angaqaba amaseli ahleliwe.
Ukuhlinzwa ngempumelelo kwenziwa, emva kwalokho i-insulin yayingasadingeki ezigulini ezinesifo sikashukela sohlobo 1. Isitho sabuyisela inani lamaseli we-beta, ukwakheka kwe-insulin yayo kwaqala kabusha. Ngemuva kokuhlinzwa, ukwelashwa kwe-immunosuppressive kwenziwa ukuze kuvinjelwe ukwenqatshwa.
Ividiyo emisebenzini kashukela noshukela:
Izikhungo zezokwelapha zisebenza ukubheka ukuthi kungenzeka yini ukuthi kufakwe i-pancreas kusuka engulube. Izidakamizwa zokuqala zokwelapha ushukela zisanda zisebenzisa izingxenye zamanyemba wezingulube.
Ososayensi bayavuma ukuthi izifundo ziyadingeka ezakhiweni nasekusebenzeni kwezigcawu zeLangerhans ngenxa yenani elikhulu lemisebenzi ebalulekile eyenziwe ngama-hormone kuyo.
Ukungena njalo kwama-hormone okufakelwa akusizi ekunqobeni lesi sifo futhi kulinyaza izinga lempilo yesiguli. Ukwehlulwa kwale ngxenye encane yamanyikwe kubangela ukuphazamiseka okukhulu ekusebenzeni komzimba wonke, ngakho-ke izifundo ziyaqhubeka.
