Biomaterial Database

Evidence that nitric oxide causes calcium-independent release of [3H] dopamine from rat striatum in vitro. 1996

T L Stewart, and A D Michel, and M D Black, and P P Humphrey

Department of Pharmacology, Glaxo Institute of Applied Pharmacology, Cambridge University, England.

Nitric oxide (NO), liberated from the photoactive donor Roussin's black salt (RBS), was investigated for its ability to release tritium from [3H]dopamine-loaded rat striatal slices. Our results show that illumination of RBS-pretreated striatal slices caused an increase in basal dopamine release, which was reduced by approximately 73% in the presence of oxyhaemoglobin (10 microM), indicating that it was mediated by liberation of NO. The release was insensitive to removal of extracellular calcium yet was not due to gross cellular damage of the tissue, as there was no detectable increase in lactate dehydrogenase release. Chelation of intracellular calcium with 1,2-bis(o-amino-phenoxy)ethane-N,N,N',N'-tetraacetic acid tetra(acetoxymethyl) ester (BAPTA-AM; 10 microM) had no effect on the dopamine release stimulated by illumination of RBS-pretreated slices. The concentration of BAPTA-AM was adequate to chelate intracellular calcium because it inhibited release evoked by the calcium ionophore ionomycin (10 microM). Superfusion with zaprinast (10 microM) had no effect on RBS-induced dopamine release, suggesting that a mechanism independent of cyclic GMP is involved. This study indicates that NO has a stimulatory effect on striatal dopamine release in vitro that is independent of calcium.

UI	MeSH Term	Description	Entries
D007502	Iron Chelating Agents	Organic chemicals that form two or more coordination links with an iron ion. Once coordination has occurred, the complex formed is called a chelate. The iron-binding porphyrin group of hemoglobin is an example of a metal chelate found in biological systems.	Iron Chelates,Agents, Iron Chelating,Chelates, Iron,Chelating Agents, Iron
D008297	Male		Males
D009569	Nitric Oxide	A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.	Endogenous Nitrate Vasodilator,Mononitrogen Monoxide,Nitric Oxide, Endothelium-Derived,Nitrogen Monoxide,Endothelium-Derived Nitric Oxide,Monoxide, Mononitrogen,Monoxide, Nitrogen,Nitrate Vasodilator, Endogenous,Nitric Oxide, Endothelium Derived,Oxide, Nitric,Vasodilator, Endogenous Nitrate
D009603	Nitroso Compounds	Organic compounds containing the nitroso (-N	Compounds, Nitroso
D010782	Photolysis	Chemical bond cleavage reactions resulting from absorption of radiant energy.	Photodegradation
D011688	Purinones		Oxopurines
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002614	Chelating Agents	Chemicals that bind to and remove ions from solutions. Many chelating agents function through the formation of COORDINATION COMPLEXES with METALS.	Chelating Agent,Chelator,Complexons,Metal Antagonists,Chelators,Metal Chelating Agents,Agent, Chelating,Agents, Chelating,Agents, Metal Chelating,Antagonists, Metal,Chelating Agents, Metal
D003342	Corpus Striatum	Striped GRAY MATTER and WHITE MATTER consisting of the NEOSTRIATUM and paleostriatum (GLOBUS PALLIDUS). It is located in front of and lateral to the THALAMUS in each cerebral hemisphere. The gray substance is made up of the CAUDATE NUCLEUS and the lentiform nucleus (the latter consisting of the GLOBUS PALLIDUS and PUTAMEN). The WHITE MATTER is the INTERNAL CAPSULE.	Lenticular Nucleus,Lentiform Nucleus,Lentiform Nuclei,Nucleus Lentiformis,Lentiformis, Nucleus,Nuclei, Lentiform,Nucleus, Lenticular,Nucleus, Lentiform,Striatum, Corpus
D004298	Dopamine	One of the catecholamine NEUROTRANSMITTERS in the brain. It is derived from TYROSINE and is the precursor to NOREPINEPHRINE and EPINEPHRINE. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (RECEPTORS, DOPAMINE) mediate its action.	Hydroxytyramine,3,4-Dihydroxyphenethylamine,4-(2-Aminoethyl)-1,2-benzenediol,Dopamine Hydrochloride,Intropin,3,4 Dihydroxyphenethylamine,Hydrochloride, Dopamine