Biomaterial Database

Kinetic mechanism of chlorpromazine inhibition of erythrocyte 3-O-methylglucose transport. 1983

N E Owen, and R B Gunn

The kinetic mechanism of chlorpromazine inhibition of erythrocyte hexose transport was investigated using the non-metabolizable glucose analog 3-O-methylglucose. It was found that chlorpromazine added to the external medium is a non-competitive inhibitor of both equilibrium exchange and net 3-O-methylglucose transport at pH 7.8, 15 degrees C. The Ki for equilibrium exchange is 76 +/- 21 microM. When net efflux and equilibrium exchange were measured on the same population of cells the equilibrium exchange was 2.5-times the maximum net efflux. The percent reduction of 3-O-methylglucose flux by chlorpromazine is dependent upon chlorpromazine concentration and not 3-O-methylglucose concentration as expected for a non-competitive inhibitor. Equilibrium exchange and net efflux show the same extent of inhibition at each concentration of chlorpromazine evaluated. These results suggest that exchange and net efflux of 3-O-methylglucose in the human erythrocyte may share a common transport system.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008757	Methylglucosides		Methylglucopyranosides
D008759	Methylglycosides
D002746	Chlorpromazine	The prototypical phenothiazine antipsychotic drug. Like the other drugs in this class chlorpromazine's antipsychotic actions are thought to be due to long-term adaptation by the brain to blocking DOPAMINE RECEPTORS. Chlorpromazine has several other actions and therapeutic uses, including as an antiemetic and in the treatment of intractable hiccup.	Aminazine,Chlorazine,Chlordelazine,Chlorpromazine Hydrochloride,Contomin,Fenactil,Largactil,Propaphenin,Thorazine,Hydrochloride, Chlorpromazine
D004912	Erythrocytes	Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.	Blood Cells, Red,Blood Corpuscles, Red,Red Blood Cells,Red Blood Corpuscles,Blood Cell, Red,Blood Corpuscle, Red,Erythrocyte,Red Blood Cell,Red Blood Corpuscle
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001693	Biological Transport, Active	The movement of materials across cell membranes and epithelial layers against an electrochemical gradient, requiring the expenditure of metabolic energy.	Active Transport,Uphill Transport,Active Biological Transport,Biologic Transport, Active,Transport, Active Biological,Active Biologic Transport,Transport, Active,Transport, Active Biologic,Transport, Uphill
D019325	3-O-Methylglucose	A non-metabolizable glucose analogue that is not phosphorylated by hexokinase. 3-O-Methylglucose is used as a marker to assess glucose transport by evaluating its uptake within various cells and organ systems. (J Neurochem 1993;60(4):1498-504)	3-O-Methyl-D-Glucose,3 O Methyl D Glucose,3 O Methylglucose