Carnitine: A constituent of STRIATED MUSCLE and LIVER. It is an amino acid derivative and an essential cofactor for fatty acid metabolism.Carnitine O-Palmitoyltransferase: An enzyme that catalyzes reversibly the conversion of palmitoyl-CoA to palmitoylcarnitine in the inner mitochondrial membrane. EC 2.3.1.21.Carnitine O-Acetyltransferase: An enzyme that catalyzes the formation of O-acetylcarnitine from acetyl-CoA plus carnitine. EC 2.3.1.7.Carnitine Acyltransferases: Acyltransferases in the inner mitochondrial membrane that catalyze the reversible transfer of acyl groups from acyl-CoA to L-carnitine and thereby mediate the transport of activated fatty acids through that membrane. EC 2.3.1.Acetylcarnitine: An acetic acid ester of CARNITINE that facilitates movement of ACETYL COA into the matrices of mammalian MITOCHONDRIA during the oxidation of FATTY ACIDS.gamma-Butyrobetaine Dioxygenase: An enzyme that catalyzes the HYDROXYLATION of gamma-butyrobetaine to L-CARNITINE. It is the last enzyme in the biosynthetic pathway of L-CARNITINE and is dependent on alpha-ketoglutarate; IRON; ASCORBIC ACID; and OXYGEN.Malonyl Coenzyme A: A coenzyme A derivative which plays a key role in the fatty acid synthesis in the cytoplasmic and microsomal systems.Organic Cation Transport Proteins: A family of proteins involved in the transport of organic cations. They play an important role in the elimination of a variety of endogenous substances, xenobiotics, and their metabolites from the body.Palmitoylcarnitine: A long-chain fatty acid ester of carnitine which facilitates the transfer of long-chain fatty acids from cytoplasm into mitochondria during the oxidation of fatty acids.Palmitoyl Coenzyme A: A fatty acid coenzyme derivative which plays a key role in fatty acid oxidation and biosynthesis.Acyltransferases: Enzymes from the transferase class that catalyze the transfer of acyl groups from donor to acceptor, forming either esters or amides. (From Enzyme Nomenclature 1992) EC 2.3.Betaine: A naturally occurring compound that has been of interest for its role in osmoregulation. As a drug, betaine hydrochloride has been used as a source of hydrochloric acid in the treatment of hypochlorhydria. Betaine has also been used in the treatment of liver disorders, for hyperkalemia, for homocystinuria, and for gastrointestinal disturbances. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1341)Acyl Coenzyme A: S-Acyl coenzyme A. Fatty acid coenzyme A derivatives that are involved in the biosynthesis and oxidation of fatty acids as well as in ceramide formation.Pentanoic AcidsCoenzyme AMitochondria, Liver: Mitochondria in hepatocytes. As in all mitochondria, there are an outer membrane and an inner membrane, together creating two separate mitochondrial compartments: the internal matrix space and a much narrower intermembrane space. In the liver mitochondrion, an estimated 67% of the total mitochondrial proteins is located in the matrix. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p343-4)Vitamin B Deficiency: A condition due to deficiency in any member of the VITAMIN B COMPLEX. These B vitamins are water-soluble and must be obtained from the diet because they are easily lost in the urine. Unlike the lipid-soluble vitamins, they cannot be stored in the body fat.Epoxy Compounds: Organic compounds that include a cyclic ether with three ring atoms in their structure. They are commonly used as precursors for POLYMERS such as EPOXY RESINS.Fatty Acids: Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)Ketone Bodies: The metabolic substances ACETONE; 3-HYDROXYBUTYRIC ACID; and acetoacetic acid (ACETOACETATES). They are produced in the liver and kidney during FATTY ACIDS oxidation and used as a source of energy by the heart, muscle and brain.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.Ergothioneine: A naturally occurring metabolite of HISTIDINE that has antioxidant properties.Starvation: Lengthy and continuous deprivation of food. (Stedman, 25th ed)3-Hydroxybutyric Acid: BUTYRIC ACID substituted in the beta or 3 position. It is one of the ketone bodies produced in the liver.Lipid Metabolism, Inborn Errors: Errors in the metabolism of LIPIDS resulting from inborn genetic MUTATIONS that are heritable.Reye Syndrome: A form of encephalopathy with fatty infiltration of the LIVER, characterized by brain EDEMA and VOMITING that may rapidly progress to SEIZURES; COMA; and DEATH. It is caused by a generalized loss of mitochondrial function leading to disturbances in fatty acid and CARNITINE metabolism.Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).Palmitic Acids: A group of 16-carbon fatty acids that contain no double bonds.Rats, Inbred Strains: Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.Palmitates: Salts and esters of the 16-carbon saturated monocarboxylic acid--palmitic acid.Microbodies: Electron-dense cytoplasmic particles bounded by a single membrane, such as PEROXISOMES; GLYOXYSOMES; and glycosomes.Hyperammonemia: Elevated level of AMMONIA in the blood. It is a sign of defective CATABOLISM of AMINO ACIDS or ammonia to UREA.Methylhydrazines: Hydrazines substituted by one or more methyl groups in any position.Mersalyl: A toxic thiol mercury salt formerly used as a diuretic. It inhibits various biochemical functions, especially in mitochondria, and is used to study those functions.Caprylates: Derivatives of caprylic acid. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a carboxy terminated eight carbon aliphatic structure.Mitochondria, Muscle: Mitochondria of skeletal and smooth muscle. It does not include myocardial mitochondria for which MITOCHONDRIA, HEART is available.Hydroxybutyrates: Salts and esters of hydroxybutyric acid.Muscles: Contractile tissue that produces movement in animals.Clofibrate: A fibric acid derivative used in the treatment of HYPERLIPOPROTEINEMIA TYPE III and severe HYPERTRIGLYCERIDEMIA. (From Martindale, The Extra Pharmacopoeia, 30th ed, p986)Kinetics: The rate dynamics in chemical or physical systems.Acyl-CoA Dehydrogenase: A flavoprotein oxidoreductase that has specificity for medium-chain fatty acids. It forms a complex with ELECTRON TRANSFERRING FLAVOPROTEINS and conveys reducing equivalents to UBIQUINONE.Lipid Metabolism: Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.Myocardium: The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.