Biomaterial Database

Release of noradrenaline from the cat spleen by sodium deprivation. 1973

A G Garcia, and S M Kirpekar

1. The endogenous noradrenaline content of cat spleen slices was markedly reduced when the slices were incubated at 37 degrees C in a medium in which sodium was replaced by sucrose, lithium, choline or potassium. Depletion of tissue noradrenaline was accounted for by its release into the incubating medium. At an external sodium concentration of 20 mM, about 50% depletion was obtained in 2 hours.2. The enhanced release induced by sodium deprivation occurred in the absence of calcium, with or without ethyleneglycol-bis (beta-aminoethyl ether) N,N' tetraacetic acid. Manganese potentiated release, while magnesium was without effect.3. Ouabain caused a dose-dependent release of noradrenaline which was partially calcium-dependent. Removal of potassium from the incubation medium caused some release, which was potentiated in 25 mM sodium Krebs solution or by ouabain.4. At 4 degrees C, the release did not occur in sodium-free medium.5. Dinitrophenol did not affect the loss of noradrenaline caused by sodium withdrawal. Iodoacetic acid and N-ethylmaleimide caused a time-dependent depletion of noradrenaline. Tetracaine caused release and partly opposed the release caused by sodium deprivation. Tetrodotoxin had no effect. Guanethidine, but not phenoxybenzamine, released noradrenaline and potentiated the release induced by sodium withdrawal.6. The rate of release of (3)H-noradrenaline from reserpine-treated spleen slices was not altered by sodium withdrawal.7. Uptake-retention of (3)H-noradrenaline in slices depleted of their endogenous noradrenaline content by sodium deprivation was about 60% of the control slices. This was effectively blocked by cocaine. Release of (3)H-noradrenaline evoked by high potassium from both control and treated slices was calcium-dependent.8. It is suggested that sodium-potassium-activated ATPase maintains the integrity of the axonal membrane, and any procedure which depresses the activity of the enzyme or the sodium-potassium pump would cause transmitter release by causing temporary disturbance in the membrane. Evidence is presented to suggest that vesicles depleted of their endogenous noradrenaline content by sodium deprivation are re-used for the storage and release of transmitter.

UI	MeSH Term	Description	Entries
D007210	Indoleacetic Acids	Acetic acid derivatives of the heterocyclic compound indole. (Merck Index, 11th ed)	Auxin,Auxins,Indolylacetic Acids,Acids, Indoleacetic,Acids, Indolylacetic
D008274	Magnesium	A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
D008345	Manganese	A trace element with atomic symbol Mn, atomic number 25, and atomic weight 54.94. It is concentrated in cell mitochondria, mostly in the pituitary gland, liver, pancreas, kidney, and bone, influences the synthesis of mucopolysaccharides, stimulates hepatic synthesis of cholesterol and fatty acids, and is a cofactor in many enzymes, including arginase and alkaline phosphatase in the liver. (From AMA Drug Evaluations Annual 1992, p2035)
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
D010042	Ouabain	A cardioactive glycoside consisting of rhamnose and ouabagenin, obtained from the seeds of Strophanthus gratus and other plants of the Apocynaceae; used like DIGITALIS. It is commonly used in cell biological studies as an inhibitor of the NA(+)-K(+)-EXCHANGING ATPASE.	Acocantherin,G-Strophanthin,Acolongifloroside K,G Strophanthin
D010477	Perfusion	Treatment process involving the injection of fluid into an organ or tissue.	Perfusions
D010643	Phenoxybenzamine	An alpha-adrenergic antagonist with long duration of action. It has been used to treat hypertension and as a peripheral vasodilator.	Dibenylene,Dibenyline,Dibenziran,Dibenzylin,Dibenzyline,Dibenzyran,Phenoxybenzamine Hydrochloride,Hydrochloride, Phenoxybenzamine
D011188	Potassium	An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
D012110	Reserpine	An alkaloid found in the roots of Rauwolfia serpentina and R. vomitoria. Reserpine inhibits the uptake of norepinephrine into storage vesicles resulting in depletion of catecholamines and serotonin from central and peripheral axon terminals. It has been used as an antihypertensive and an antipsychotic as well as a research tool, but its adverse effects limit its clinical use.	Raunervil,Raupasil,Rausedil,Rausedyl,Serpasil,Serpivite,V-Serp,V Serp
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