Effects of two oxadiazolidinones on cholinesterases and acetylcholine receptors

Conference · Wed Mar 05 04:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:6991916

Bakry, N; Lockyer, S; Sherby, S; Eldefrawi, A; Eldefrawi, M

Inhibition of acetylcholinesterase (AChE) and butyryl cholinesterase (BuChE) by 3-(2,3-dihydro-2,2-dimethyl-benzofuran-'7-yl)-5-methoxy-1,3,4-oxadiazol-2(/sup 3/H)-one (DBOX) and 3-(2-methoxyphenyl)-5-methoxy-1,3,4-oxadiazol-2(/sup 3/H)-one (MPOX) was measured by the Ellmann spectrophotometric method. Inhibition was quasi first order and irreversible. DBOX was 2-3 orders of magnitude more potent than MPOX. Housefly brain AChE and horse serum BuChE were more sensitive than AChEs of red blood cells or eel and Torpedo electric organs. It is suggested that the nonesteratic oxadiazolidinones are activated to carbanillates on the surface of the enzyme and produce a carbanillated enzyme which ages rapidly. Carbamate anticholinesterases protected AChE against carbanillation as they did against phosphorylation. At higher concentrations, the two oxadiazolidinones also affected binding of (/sup 125/I) ..cap alpha.. bungarotoxin and (/sup 3/H)perhydrohistrionicotoxin to Torpedo nicotinic acetylcholine receptors, but did not affect binding of (/sup 3/H)quinuclidinyl benzilate to rat brain muscarinic receptors.

• Research Organization: Univ. of Maryland School of Medicine, Baltimore
• OSTI ID: 6991916
• Report Number(s): CONF-8604222-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 45:4
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACETYLCHOLINE
AMINES
AMMONIUM COMPOUNDS
ANIMALS
ANTIGENS
AQUATIC ORGANISMS
ARTHROPODS
AUTONOMIC NERVOUS SYSTEM AGENTS
BENZILIC ACID
BETA DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL EFFECTS
CARBOXYLESTERASES
CARBOXYLIC ACIDS
CHOLINESTERASE
DAYS LIVING RADIOISOTOPES
DIPTERA
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ENZYME ACTIVITY
ENZYME INHIBITORS
ENZYMES
ESTERASES
ESTERS
FISHES
FLIES
HORSES
HYDROLASES
HYDROXY ACIDS
INHIBITION
INSECTS
INTERMEDIATE MASS NUCLEI
INVERTEBRATES
IODINE 125
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LABELLED COMPOUNDS
MAMMALS
MATERIALS
MEMBRANE PROTEINS
NEUROREGULATORS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
PARASYMPATHOMIMETICS
PROTEINS
QUATERNARY COMPOUNDS
RADIOISOTOPES
RATS
REACTION KINETICS
RECEPTORS
RODENTS
TOXIC MATERIALS
TOXINS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES