Biomaterial Database

The blood-brain barrier of the rat choroid plexus. 1975

D A Davis, and T H Milhorat

Following intravenous injection, cytochrome c traverses the capillary endothelium of the rat choroid plexus and permeates the perivascular space and the extracellular space between epithelial cells. The tracer is incorporated into pinocytotic vesicles adjacent to the lateral and basal plasmalemmas. Thereafter, cytochrome c is incorporated into multivesicular and dense bodies. Tracerladen vesicles were not found to fuse with the apical plasmalemma and cytochrome c was not discharged into the cerebral ventricles. Acid phosphatase activity of the choroidal epithelium after the administration of cytochrome c was greatly increased and localized in the same intracellular sites shown for cytochrome c. These data suggest that cytochrome c and possibly other proteins that penetrate the choroidal stroma are taken up by the choroidal epithelium and subsequently degraded in lysosomal vesicles. This heterolytic mechanism may be an important means for preventing the entry of certain substances such as proteins into CSF and subsequently into nervous tissue.

UI	MeSH Term	Description	Entries
D007275	Injections, Intravenous	Injections made into a vein for therapeutic or experimental purposes.	Intravenous Injections,Injection, Intravenous,Intravenous Injection
D008247	Lysosomes	A class of morphologically heterogeneous cytoplasmic particles in animal and plant tissues characterized by their content of hydrolytic enzymes and the structure-linked latency of these enzymes. The intracellular functions of lysosomes depend on their lytic potential. The single unit membrane of the lysosome acts as a barrier between the enzymes enclosed in the lysosome and the external substrate. The activity of the enzymes contained in lysosomes is limited or nil unless the vesicle in which they are enclosed is ruptured or undergoes MEMBRANE FUSION. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed).	Autolysosome,Autolysosomes,Lysosome
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D010873	Pinocytosis	The engulfing of liquids by cells by a process of invagination and closure of the cell membrane to form fluid-filled vacuoles.	Pinocytoses
D011506	Proteins	Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.	Gene Products, Protein,Gene Proteins,Protein,Protein Gene Products,Proteins, Gene
D001812	Blood-Brain Barrier	Specialized non-fenestrated tightly-joined ENDOTHELIAL CELLS with TIGHT JUNCTIONS that form a transport barrier for certain substances between the cerebral capillaries and the BRAIN tissue.	Brain-Blood Barrier,Hemato-Encephalic Barrier,Barrier, Blood-Brain,Barrier, Brain-Blood,Barrier, Hemato-Encephalic,Barriers, Blood-Brain,Barriers, Brain-Blood,Barriers, Hemato-Encephalic,Blood Brain Barrier,Blood-Brain Barriers,Brain Blood Barrier,Brain-Blood Barriers,Hemato Encephalic Barrier,Hemato-Encephalic Barriers
D002196	Capillaries	The minute vessels that connect arterioles and venules.	Capillary Beds,Sinusoidal Beds,Sinusoids,Bed, Sinusoidal,Beds, Sinusoidal,Capillary,Capillary Bed,Sinusoid,Sinusoidal Bed
D002831	Choroid Plexus	A villous structure of tangled masses of BLOOD VESSELS contained within the third, lateral, and fourth ventricles of the BRAIN. It regulates part of the production and composition of CEREBROSPINAL FLUID.	Chorioid Plexus,Plexus Choroideus,Choroideus, Plexus,Plexus, Chorioid,Plexus, Choroid
D003574	Cytochrome c Group	A group of cytochromes with covalent thioether linkages between either or both of the vinyl side chains of protoheme and the protein. (Enzyme Nomenclature, 1992, p539)	Cytochromes Type c,Group, Cytochrome c,Type c, Cytochromes
D004727	Endothelium	A layer of epithelium that lines the heart, blood vessels (ENDOTHELIUM, VASCULAR), lymph vessels (ENDOTHELIUM, LYMPHATIC), and the serous cavities of the body.	Endotheliums