Biomaterial Database

Effects of mefloquine on Ca2+ uptake and release by dog brain microsomes. 1996

H S Lee, and M L Go

Department of Pharmacology, National University of Singapore, Republic of Singapore.

The effects of the antimalarial drug, mefloquine, on the uptake and release of Ca2+ by crude microsomes from dog brain were investigated using a spectrophotometric method. Mefloquine inhibited the inositol-1,4,5-phosphate (IP3)-induced Ca2+ release with an IC50 of 42 microM, but was a weaker inhibitor of the uptake of Ca2+ into the vesicles (IC50: 272 microM). These effects of mefloquine are in contrast to its actions on Ca2+ uptake and release by skeletal muscle microsomes, where its predominant effect was seen to be the inhibition of Ca2+ uptake into the vesicles. Mefloquine was found to be more potent than quinine as a specific inhibitor of Ca2+ release from IP3-sensitive stores in dog brain microsomes. The possibility of the drug affecting cellular IP3-linked signal transduction processes should be considered.

UI	MeSH Term	Description	Entries
D008861	Microsomes	Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	Microsome
D011803	Quinine	An alkaloid derived from the bark of the cinchona tree. It is used as an antimalarial drug, and is the active ingredient in extracts of the cinchona that have been used for that purpose since before 1633. Quinine is also a mild antipyretic and analgesic and has been used in common cold preparations for that purpose. It was used commonly and as a bitter and flavoring agent, and is still useful for the treatment of babesiosis. Quinine is also useful in some muscular disorders, especially nocturnal leg cramps and myotonia congenita, because of its direct effects on muscle membrane and sodium channels. The mechanisms of its antimalarial effects are not well understood.	Biquinate,Legatrim,Myoquin,Quinamm,Quinbisan,Quinbisul,Quindan,Quinimax,Quinine Bisulfate,Quinine Hydrochloride,Quinine Lafran,Quinine Sulfate,Quinine Sulphate,Quinine-Odan,Quinoctal,Quinson,Quinsul,Strema,Surquina,Bisulfate, Quinine,Hydrochloride, Quinine,Sulfate, Quinine,Sulphate, Quinine
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
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
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
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
D000962	Antimalarials	Agents used in the treatment of malaria. They are usually classified on the basis of their action against plasmodia at different stages in their life cycle in the human. (From AMA, Drug Evaluations Annual, 1992, p1585)	Anti-Malarial,Antimalarial,Antimalarial Agent,Antimalarial Drug,Anti-Malarials,Antimalarial Agents,Antimalarial Drugs,Agent, Antimalarial,Agents, Antimalarial,Anti Malarial,Anti Malarials,Drug, Antimalarial,Drugs, Antimalarial
D015544	Inositol 1,4,5-Trisphosphate	Intracellular messenger formed by the action of phospholipase C on phosphatidylinositol 4,5-bisphosphate, which is one of the phospholipids that make up the cell membrane. Inositol 1,4,5-trisphosphate is released into the cytoplasm where it releases calcium ions from internal stores within the cell's endoplasmic reticulum. These calcium ions stimulate the activity of B kinase or calmodulin.	1,4,5-InsP3,Inositol 1,4,5-Triphosphate,Myo-Inositol 1,4,5-Trisphosphate,1,4,5-IP3,Myoinositol 1,4,5-Triphosphate
D015767	Mefloquine	A phospholipid-interacting antimalarial drug (ANTIMALARIALS). It is very effective against PLASMODIUM FALCIPARUM with very few side effects.	Lariam,Mefloquine Hydrochloride,Mephloquine,Ro-21-5998-001,WR-142,490,WR-177,602,Ro 21 5998 001,Ro215998001,WR 142,490,WR 177,602,WR142,490,WR177,602