The blood\u2013brain barrier (BBB) is a highly specialized interface formed by endothelial cells of brain microvessels, tightly connected by junctional complexes. It separates circulating blood from the central nervous system (CNS) and strictly regulates molecular exchange. By limiting paracellular permeability and reducing vesicular transport, the BBB maintains neural homeostasis and protects the brain from toxins and fluctuations in plasma composition.<\/p>
Transport across the BBB is controlled by two complementary mechanisms. Essential nutrients and metabolites, including glucose and amino acids, are delivered by specific uptake transporters such as GLUT1 and LAT1. In contrast, powerful efflux systems, notably P-glycoprotein (ABCB1) and breast cancer resistance protein (BCRP, ABCG2), actively expel xenobiotics and many therapeutic agents back into the bloodstream. This dual function provides neuroprotection but also presents a major barrier for drug delivery to the CNS.<\/p>","categories":[{"id":63,"title":"Experimental","breadcrumb":[{"id":71,"title":"Brain"},{"id":63,"title":"Experimental"}]}],"url":"https:\/\/molmedb.upol.cz\/api\/v1\/membranes\/19","landing_page":"https:\/\/molmedb.upol.cz\/membrane\/19","created_at":"2018-06-30T20:55:26.000000Z","updated_at":"2026-06-28T12:47:29.000000Z"}}