Az emésztőrendszer megfelelő működése nélkülözhetetlen a tápanyagtranszporthoz, a felszívódáshoz, az emésztéshez és a salakanyagok kiürítéséhez, de ezenfelül fontos feladata van a patogénekkel, allergénekkel és toxinokkal szembeni védelemben és a bélrendszer homeosztázisának fenntartásában. Ezeknek a feladatoknak a koordinációját a bél ideg- és immunrendszere szoros együttműködésben végzi a belső és külső környezethez való folyamatos alkalmazkodás révén. A bél élőhelyet és tápanyagokat szolgáltat a benne élő mikroorganizmusok számára, amelyek jelentős hatással vannak a tápcsatorna fejlődésére és annak funkcionális működésére. A bélcsatorna és a benne élő mikroorganizmusok közösen végzik el az emésztést, s látják el az immun-, neuroendokrin és ingerületátviteli funkciókat. Ezt az egymással morfofunkcionálisan együttműködő struktúrát hívjuk mikrobiom–bél–agy-tengelynek, melynek kiindulópontját az enteralis idegrendszer és a bél mononukleáris sejtjei között fennálló neuroimmunológiai interakciók szolgáltatják. Összefoglaló közleményünkben ennek a fellendülő tudományterületnek a legfontosabb és legfrissebb eredményeiről, aktuális kutatási témáiról számolunk be, kiegészítve azzal, hogy milyen klinikai vonatkozásai lehetnek a jövő orvoslásában a bél–agy-tengely patológiás működésének és a bélflóra megváltozásának. Orv Hetil. 2020; 161(19): 771–779.
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