Biomaterial Database

Microsphere embolism-induced changes in noradrenaline release in the cerebral cortex in rats. 1998

H Hayashi, and K Sato, and Y Kuruhara, and S Takeo

Department of Pharmacology, Tokyo University of Pharmacy and Life Science, Tokyo, Japan.

The present study was undertaken to elucidate pathophysiological changes in noradrenaline release, phosphorylation of synapsin I and ultrastructure of the cerebrocortical nerve terminals following microsphere embolism in rats. In the microdialysis study, K+-stimulated noradrenaline release in the cerebral cortex was not altered on the 1st day but markedly decreased on the 3rd and 7th days after the embolism. Synaptosomes were isolated from the cerebral cortex of the operated animals on the 1st, 3rd and 7th days after the embolism. The level of calmodulin and the phosphorylation of synapsin I in the synaptosomes were not altered up to the 7th day, but the levels of calcium/calmodulin-dependent protein kinase II and synapsin I in the synaptosomes were significantly decreased by microsphere embolism. Electron microscopic study showed no appreciable changes in the structure of the synaptosomes on the 1st day, but a large number of clumps of synaptic vesicles were observed on the 3rd and 7th days after the embolism. These results suggest that microsphere embolism-induced changes in noradrenaline release from nerve terminals are due to a failure in the process following phosphorylation of synapsin I. Aggregation of synaptic vesicles in nerve terminals may contribute to the pathogenesis of microsphere embolism.

UI	MeSH Term	Description	Entries
D008297	Male		Males
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
D008863	Microspheres	Small uniformly-sized spherical particles, of micrometer dimensions, frequently labeled with radioisotopes or various reagents acting as tags or markers.	Latex Beads,Latex Particles,Latex Spheres,Microbeads,Bead, Latex,Beads, Latex,Latex Bead,Latex Particle,Latex Sphere,Microbead,Microsphere,Particle, Latex,Particles, Latex,Sphere, Latex,Spheres, Latex
D009638	Norepinephrine	Precursor of epinephrine that is secreted by the ADRENAL MEDULLA and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers, and of the diffuse projection system in the brain that arises from the LOCUS CERULEUS. It is also found in plants and is used pharmacologically as a sympathomimetic.	Levarterenol,Levonorepinephrine,Noradrenaline,Arterenol,Levonor,Levophed,Levophed Bitartrate,Noradrenaline Bitartrate,Noradrénaline tartrate renaudin,Norepinephrin d-Tartrate (1:1),Norepinephrine Bitartrate,Norepinephrine Hydrochloride,Norepinephrine Hydrochloride, (+)-Isomer,Norepinephrine Hydrochloride, (+,-)-Isomer,Norepinephrine d-Tartrate (1:1),Norepinephrine l-Tartrate (1:1),Norepinephrine l-Tartrate (1:1), (+,-)-Isomer,Norepinephrine l-Tartrate (1:1), Monohydrate,Norepinephrine l-Tartrate (1:1), Monohydrate, (+)-Isomer,Norepinephrine l-Tartrate (1:2),Norepinephrine l-Tartrate, (+)-Isomer,Norepinephrine, (+)-Isomer,Norepinephrine, (+,-)-Isomer
D010766	Phosphorylation	The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.	Phosphorylations
D002540	Cerebral Cortex	The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulci. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.	Allocortex,Archipallium,Cortex Cerebri,Cortical Plate,Paleocortex,Periallocortex,Allocortices,Archipalliums,Cerebral Cortices,Cortex Cerebrus,Cortex, Cerebral,Cortical Plates,Paleocortices,Periallocortices,Plate, Cortical
D002545	Brain Ischemia	Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia (HYPOXIA, BRAIN). Prolonged ischemia is associated with BRAIN INFARCTION.	Cerebral Ischemia,Ischemic Encephalopathy,Encephalopathy, Ischemic,Ischemia, Cerebral,Brain Ischemias,Cerebral Ischemias,Ischemia, Brain,Ischemias, Cerebral,Ischemic Encephalopathies
D004617	Embolism	Blocking of a blood vessel by an embolus which can be a blood clot or other undissolved material in the blood stream.	Embolus,Embolisms
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013574	Synaptosomes	Pinched-off nerve endings and their contents of vesicles and cytoplasm together with the attached subsynaptic area of the membrane of the post-synaptic cell. They are largely artificial structures produced by fractionation after selective centrifugation of nervous tissue homogenates.	Synaptosome