Biomaterial Database

Effect of tetraethylammonium and barium on the release of noradrenaline from the perfused cat spleen by nerve stimulation and potassium. 1976

S M Kirpekar, and A R Wakade, and J C Prat

The effect of tetraethylammonium (TEA) and barium on release of noradrenaline (NA) from the cat spleen by nerve stimulation or potassium was investigated. 2. In spleens perfused with normal Krebs solution, the NA output at 5 Hz was barely detectable, and the output at 30 Hz was about 5-fold greater than the output at 5 Hz. 3. TEA (1 mM) or barium (2.5 mM) increased NA output at 5 Hz by 5-fold, but did not enhance it at 30 Hz. A maximal effect of TEA was obtained at about 1-3 mM. Enhancement of NA release by TEA was readily reversible. Output of NA induced by high potassium was not affected by TEA or barium. 4. The effect of TEA on release was related to the external calcium concentration. Insignificant outputs obtained at 5 Hz in 0.1 and 0.5 mM calcium-Krebs solutions were markedly increased by TEA, and were 2- and 5-fold greater than the control output at 5 Hz in normal Krebs solution containing 2.5 mM calcium. TEA enhanced release at all calcium concentrations up to 5 mM, but maximum output was still obtained at 2.5 mM. 5. Increasing the potassium concentrations of normal Krebs solution to 10, 15 and 20 mM depressed NA outputs at 5 Hz by 50, 55 and 75% respectively, TEA (1 mM) partially antagonized the inhibitory effect of potassium on release, and in zero potassium-Krebs solution it increased output by about 50% over that obtained in normal Krebs solution. 6. The ratio of NA outputs at 30 and 5 Hz during perfusion with Krebs solution containing TEA was about 0.6, and it approached the normal value as the calcium concentration of the perfusion medium was reduced. TEA facilitated release even at 30 Hz in low-calcium solutions. 7. It is suggested that the enhancement of NA release by TEA and barium is due to the greater influx of calcium ions into the sympathetic nerves during the course of an action potential.

UI	MeSH Term	Description	Entries
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
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.
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
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
D000200	Action Potentials	Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.	Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential
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
D001464	Barium	An element of the alkaline earth group of metals. It has an atomic symbol Ba, atomic number 56, and atomic weight 138. All of its acid-soluble salts are poisonous.
D013154	Spleen	An encapsulated lymphatic organ through which venous blood filters.
D013757	Tetraethylammonium Compounds	Quaternary ammonium compounds that consist of an ammonium cation where the central nitrogen atom is bonded to four ethyl groups.	Tetramon,Tetrylammonium,Compounds, Tetraethylammonium