Biomaterial Database

Enhancement of ischemia-induced tyrosine phosphorylation of Kv1.2 by vascular endothelial growth factor via activation of phosphatidylinositol 3-kinase. 2003

Mei-Hong Qiu, and Rong Zhang, and Feng-Yan Sun

National Laboratory of Medical Neurobiology, Shanghai Medical College of, Fudan University, Shanghai, People's Republic of China.

Our studies observed that, consistent with the literature, ischemic/hypoxic insults increased the expression of voltage-gated potassium channel (Kv) 1.2 potassium channel as well as elevating the endogenous level of vascular endothelial growth factor (VEGF) in neurons of adult rat brain following middle cerebral artery occlusion and in SH-SY5Y cells after hypoxia and glucose deprivation. Concomitantly, we also observed that ischemic injury increased the tyrosine phosphorylation of Kv 1.2 in in vivo and in vitro; the introduction of exogenous VEGF could attenuate cell death in in vitro models. Furthermore, we found that the protective effect of VEGF is mediated through its up-regulative actions on the tyrosine phosphorylation of Kv 1.2, which in turn has a direct influence on cell viability after ischemic insult. In substantiation of this result, we used anti-sense methodology to suppress the expression of endogenous VEGF, which significantly inhibited the tyrosine phosphorylation of Kv 1.2 and increased cell death elicited by ischemic/hypoxic injury. Finally, the enhancement of the tyrosine phosphorylation of the channel by VEGF in neuronal cells was significantly attenuated in the presence of wortmannin, an inhibitor of phosphatidylinositol 3-kinase (PI3-K), or genestin, an inhibitor of tyrosine kinase, thus suggesting that the phosphorylation of Kv 1.2 induced by VEGF is mechanistically linked to the PI3-K pathway.

UI	MeSH Term	Description	Entries
D007150	Immunohistochemistry	Histochemical localization of immunoreactive substances using labeled antibodies as reagents.	Immunocytochemistry,Immunogold Techniques,Immunogold-Silver Techniques,Immunohistocytochemistry,Immunolabeling Techniques,Immunogold Technics,Immunogold-Silver Technics,Immunolabeling Technics,Immunogold Silver Technics,Immunogold Silver Techniques,Immunogold Technic,Immunogold Technique,Immunogold-Silver Technic,Immunogold-Silver Technique,Immunolabeling Technic,Immunolabeling Technique,Technic, Immunogold,Technic, Immunogold-Silver,Technic, Immunolabeling,Technics, Immunogold,Technics, Immunogold-Silver,Technics, Immunolabeling,Technique, Immunogold,Technique, Immunogold-Silver,Technique, Immunolabeling,Techniques, Immunogold,Techniques, Immunogold-Silver,Techniques, Immunolabeling
D008297	Male		Males
D010751	Phosphopyruvate Hydratase	A hydro-lyase that catalyzes the dehydration of 2-phosphoglycerate to form PHOSPHOENOLPYRUVATE. Several different isoforms of this enzyme exist, each with its own tissue specificity.	Enolase,Neuron-Specific Enolase,2-Phospho-D-Glycerate Hydro-Lyase,2-Phospho-D-Glycerate Hydrolase,2-Phosphoglycerate Dehydratase,Enolase 2,Enolase 3,Muscle-Specific Enolase,Nervous System-Specific Enolase,Non-Neuronal Enolase,alpha-Enolase,beta-Enolase,gamma-Enolase,2 Phospho D Glycerate Hydro Lyase,2 Phospho D Glycerate Hydrolase,2 Phosphoglycerate Dehydratase,Dehydratase, 2-Phosphoglycerate,Enolase, Muscle-Specific,Enolase, Nervous System-Specific,Enolase, Neuron-Specific,Enolase, Non-Neuronal,Hydratase, Phosphopyruvate,Hydro-Lyase, 2-Phospho-D-Glycerate,Muscle Specific Enolase,Nervous System Specific Enolase,Neuron Specific Enolase,Non Neuronal Enolase,System-Specific Enolase, Nervous,alpha Enolase,beta Enolase,gamma Enolase
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
D011233	Precipitin Tests	Serologic tests in which a positive reaction manifested by visible CHEMICAL PRECIPITATION occurs when a soluble ANTIGEN reacts with its precipitins, i.e., ANTIBODIES that can form a precipitate.	Precipitin Test,Test, Precipitin,Tests, Precipitin
D011419	Propidium	Quaternary ammonium analog of ethidium; an intercalating dye with a specific affinity to certain forms of DNA and, used as diiodide, to separate them in density gradients; also forms fluorescent complexes with cholinesterase which it inhibits.	Propidium Diiodide,Propidium Iodide,Diiodide, Propidium,Iodide, Propidium
D002470	Cell Survival	The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.	Cell Viability,Cell Viabilities,Survival, Cell,Viabilities, Cell,Viability, Cell
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
D004347	Drug Interactions	The action of a drug that may affect the activity, metabolism, or toxicity of another drug.	Drug Interaction,Interaction, Drug,Interactions, Drug
D004789	Enzyme Activation	Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.	Activation, Enzyme,Activations, Enzyme,Enzyme Activations