tight junction

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Related to tight junction: gap junction, Desmosomes, Adherens junction

zo·nu·la oc·clu·'dens

tight junctions formed by the fusion of integral proteins of the lateral cell membranes of adjacent epithelial cells, limiting transepithelial permeability.
Farlex Partner Medical Dictionary © Farlex 2012

tight junc·tion

(tīt jŭngk'shŭn)
An intercellular junction between epithelial cells in which the outer leaflets of lateral cell membranes fuse to form a variable number of parallel interweaving strands that greatly reduce transepithelial permeability to macromolecules, solutes, and water through the paracellular route.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

tight junction 

Refers to cells in which their membranes are fused rather than separated by a small extracellular space. The movement of substances through that space is restricted. Syn. zonulae occludentes. See blood-brain barrier.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann
References in periodicals archive ?
Molecular organization of tricellular tight junctions. Tissue Barriers 2014; 2: e28960.
Caption: Figure 4: Human placenta-derived mesenchymal stem cells (PD-MSCs) enhanced the expression of tight junction proteins at 24 hours after ICH induction but did not affect the expression of coagulation factor VII mRNA.
Intestinal epithelia interspersed with diverse types of cells regenerate every 3-7 days, and these cells attach with tight junction proteins and form a physical barrier to prevent leaking of intestinal contents.
ECs: endothelial cells; SCI: spinal cord injury; TJs: tight junctions; GJs: gap junctions; ZO: zona occludin; PKC: protein kinase C; CaMKII: [Ca.sup.2+]/calmodulin-dependent kinase II; HCs: hemichannels; GJIC: gap junction intercellular communication; A[beta]: amyloid [beta].
Wang, "Changes in gut microbial populations, intestinal morphology, expression of tight junction proteins, and cytokine production between two pig breeds after challenge with Escherichia coli K88: a comparative study," Journal of Animal Science, vol.
Hoa et al., "TNF-alpha-induced increase in intestinal epithelial tight junction permeability requires NF-kappa B activation," American Journal of Physiology.
For example, acetaldehyde destabilizes tight junctions by redistributing proteins (Dunagan et al.
Zonulin is a protein that increases the intestinal permeability in small intestinal system by modulating the intracellular tight junctions.
This 47kDa single protein is isolated from a membrane complex (claudin-occludin-guanylate kinase-like proteins ZO-1, ZO-2, and ZO-3) forming tight junction (TJ) in the apical part of intestinal endothelium [6].