Biomaterial Database

alpha-Ketoisocaproate stimulates branched-chain amino acid transaminase in kidney and muscle. 1979

W E Mitch, and W Chan

We have reported that branched-chain amino acid transaminase (BATase) activity of isolated rat kidney is stimulated by perfusion with alpha-ketoisocaproate (KL). This study examines the mechanism of this effect in kidney and documents that stimulation occurs in intact skeletal muscle. Increased activity was not attributable to synthesis of enzyme because it occurred in the presence of cycloheximide. The in vivo degradation rate of BATase estimated from sequential measurements of activity following intravenous cycloheximide was longer than 90 min, whereas during in vitro perfusion stimulation could be detected within 5 min. Incubation of supernatant from kidney homogenate with KL stimulated BATase; incubation with alpha-keto-beta-methylvalerate (KI), alpha-ketoisovalerate (KV), leucine (leu), or isovaleryl CoA did not. Perfusion of rat hindquarter with KL increased muscle BATase activity; perfusion with acetoacetate, KI, KV, or leu did not. Again, cycloheximide studies indicated a direct effect of KL on muscle BATase. These findings suggest that alpha-ketoisocaproate can increase BATase activity and thus may be involved in regulation of its activity.

UI	MeSH Term	Description	Entries
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D008297	Male		Males
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D010477	Perfusion	Treatment process involving the injection of fluid into an organ or tissue.	Perfusions
D002208	Caproates	Derivatives of caproic acid. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a carboxy terminated six carbon aliphatic structure.	Hexanoates,Caproic Acid Derivatives,Caproic Acids,Hexanoic Acid Derivatives,Hexanoic Acids,Acid Derivatives, Caproic,Acid Derivatives, Hexanoic,Acids, Caproic,Acids, Hexanoic,Derivatives, Caproic Acid,Derivatives, Hexanoic Acid
D003513	Cycloheximide	Antibiotic substance isolated from streptomycin-producing strains of Streptomyces griseus. It acts by inhibiting elongation during protein synthesis.	Actidione,Cicloheximide
D000597	Amino Acids, Branched-Chain	Amino acids which have a branched carbon chain.	Branched-Chain Amino Acid,Amino Acids, Branched Chain,Acid, Branched-Chain Amino,Acids, Branched-Chain Amino,Amino Acid, Branched-Chain,Branched Chain Amino Acid,Branched-Chain Amino Acids
D000637	Transaminases	A subclass of enzymes of the transferase class that catalyze the transfer of an amino group from a donor (generally an amino acid) to an acceptor (generally a 2-keto acid). Most of these enzymes are pyridoxyl phosphate proteins. (Dorland, 28th ed) EC 2.6.1.	Aminotransferase,Aminotransferases,Transaminase
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
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor