Biomaterial Database

Anion blockers inhibit impulse-evoked quantal transmitter release at the crayfish neuromuscular junction. 1982

W D Niles, and D O Smith

1. The effects of the anion-transport blocking reagents Probenecid, 4,4'diisothiocyanostilbene-2,2'-disulphonate (DIDS), and pyridoxal phosphate on the number of quanta released (m) and the time course of the probability of quantal release, alpha(t), following an action potential were studied at single synaptic sites on the opener muscle in the crayfish leg.2. Low concentrations (10-50 muM) of DIDS or Probenecid produced decreases in m to about 30-50% of the initial value; at higher concentrations (100 muM or greater), evoked release failed. Much greater concentrations (500 muM) of pyridoxal phosphate were necessary to produce decreases in m.3. Synaptic depression in 50 muM-Probenecid was reversible by removing the agent; after treatment with 50 muM-DIDS, however, m partially regained the initial value upon removal of the drug.4. The time course of alpha(t) after an action potential was unaffected by any of the reagents.5. It is concluded that the reagents decrease the number of quanta evoked by a nerve impulse by decreasing the magnitude, but not the time course, of the average rate of quantal release following an action potential; it is suggested that nerves and other secretory cells may share a common mechanism during exocytosis that is subject to modification by these agents.

UI	MeSH Term	Description	Entries
D009469	Neuromuscular Junction	The synapse between a neuron and a muscle.	Myoneural Junction,Nerve-Muscle Preparation,Junction, Myoneural,Junction, Neuromuscular,Junctions, Myoneural,Junctions, Neuromuscular,Myoneural Junctions,Nerve Muscle Preparation,Nerve-Muscle Preparations,Neuromuscular Junctions,Preparation, Nerve-Muscle,Preparations, Nerve-Muscle
D011339	Probenecid	The prototypical uricosuric agent. It inhibits the renal excretion of organic anions and reduces tubular reabsorption of urate. Probenecid has also been used to treat patients with renal impairment, and, because it reduces the renal tubular excretion of other drugs, has been used as an adjunct to antibacterial therapy.	Benecid,Benemid,Benuryl,Pro-Cid,Probecid,Probenecid Weimer
D011732	Pyridoxal Phosphate	This is the active form of VITAMIN B 6 serving as a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate (PYRIDOXAMINE).	Pyridoxal 5-Phosphate,Pyridoxal-P,Phosphate, Pyridoxal,Pyridoxal 5 Phosphate,Pyridoxal P
D003400	Astacoidea	A superfamily of various freshwater CRUSTACEA, in the infraorder Astacidea, comprising the crayfish. Common genera include Astacus and Procambarus. Crayfish resemble lobsters, but are usually much smaller.	Astacus,Crayfish,Procambarus,Astacoideas,Crayfishs
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
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
D012636	Secretory Rate	The amount of a substance secreted by cells or by a specific organ or organism over a given period of time; usually applies to those substances which are formed by glandular tissues and are released by them into biological fluids, e.g., secretory rate of corticosteroids by the adrenal cortex, secretory rate of gastric acid by the gastric mucosa.	Rate, Secretory,Rates, Secretory,Secretory Rates
D012856	4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid	A non-penetrating amino reagent (commonly called SITS) which acts as an inhibitor of anion transport in erythrocytes and other cells.	4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid, Disodium Salt,SITS,SITS Disodium Salt,4 Acetamido 4' isothiocyanatostilbene 2,2' disulfonic Acid,Disodium Salt, SITS
D013267	Stilbenes	Organic compounds that contain 1,2-diphenylethylene as a functional group.	Stilbene,Stilbene Derivative,Stilbene Derivatives,Stilbenoid,Stilbenoids,Derivative, Stilbene,Derivatives, Stilbene