Biomaterial Database

Microdialysis of lipophilic compounds: a methodological study. 1991

C Carneheim, and L Ståhle

Department of Experimental Biology, KABI Pharmacia Parenterals AB, Stockholm, Sweden.

The influence of perfusion medium on in vitro recovery of 14C-oleate to microdialysis probes was investigated. Four perfusion media were investigated: water, 4% bovine serum albumin (BSA) in Ringer solution, 2.25% glycerol in water and a 20% soybean oil/egg phospholipid emulsion (Intralipid). The following order of recovery was found (highest recovery first): BSA = Intralipid greater than glycerol greater than water. The recoveries at 0.5 microliter/min. perfusion rate of the dialysis probe were 4.8%, 4.4%, 2.6% and 1.2% respectively. It was attempted to measure 14C-oleate after intravenous infusion. The samples were extracted with hexane/isopropyl alcohol in order to separate the free fatty acid from products of oxidation which are hydrophilic. Dialysis probes were implanted in interscapular adipose tissue, epididymal fat, muscle, liver and jugular vein of rats. We were not able to detect unbound fatty acids, neither basally nor after stimulation with 1 mg/kg norepinephrine intraperitoneally. However, products of oxidation from the infused oleate were released in response to norepinephrine stimulation. It is concluded that the recovery of lipophilic compounds in microdialysis devices can be improved by means of a lipophilic perfusion medium or by means of e.g. BSA to which the compound binds. The free fatty acid levels were too small to be measureable in vivo in the present study.

UI	MeSH Term	Description	Entries
D007275	Injections, Intravenous	Injections made into a vein for therapeutic or experimental purposes.	Intravenous Injections,Injection, Intravenous,Intravenous Injection
D008297	Male		Males
D009638	Norepinephrine	Precursor of epinephrine that is secreted by the ADRENAL MEDULLA and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers, and of the diffuse projection system in the brain that arises from the LOCUS CERULEUS. It is also found in plants and is used pharmacologically as a sympathomimetic.	Levarterenol,Levonorepinephrine,Noradrenaline,Arterenol,Levonor,Levophed,Levophed Bitartrate,Noradrenaline Bitartrate,Noradrénaline tartrate renaudin,Norepinephrin d-Tartrate (1:1),Norepinephrine Bitartrate,Norepinephrine Hydrochloride,Norepinephrine Hydrochloride, (+)-Isomer,Norepinephrine Hydrochloride, (+,-)-Isomer,Norepinephrine d-Tartrate (1:1),Norepinephrine l-Tartrate (1:1),Norepinephrine l-Tartrate (1:1), (+,-)-Isomer,Norepinephrine l-Tartrate (1:1), Monohydrate,Norepinephrine l-Tartrate (1:1), Monohydrate, (+)-Isomer,Norepinephrine l-Tartrate (1:2),Norepinephrine l-Tartrate, (+)-Isomer,Norepinephrine, (+)-Isomer,Norepinephrine, (+,-)-Isomer
D009829	Oleic Acids	A group of fatty acids that contain 18 carbon atoms and a double bond at the omega 9 carbon.	Octadecenoic Acids,Acids, Octadecenoic,Acids, Oleic
D010477	Perfusion	Treatment process involving the injection of fluid into an organ or tissue.	Perfusions
D011919	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.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D003956	Dialysis	A process of selective diffusion through a membrane. It is usually used to separate low-molecular-weight solutes which diffuse through the membrane from the colloidal and high-molecular-weight solutes which do not. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Dialyses
D006493	Heparin	A highly acidic mucopolysaccharide formed of equal parts of sulfated D-glucosamine and D-glucuronic acid with sulfaminic bridges. The molecular weight ranges from six to twenty thousand. Heparin occurs in and is obtained from liver, lung, mast cells, etc., of vertebrates. Its function is unknown, but it is used to prevent blood clotting in vivo and vitro, in the form of many different salts.	Heparinic Acid,alpha-Heparin,Heparin Sodium,Liquaemin,Sodium Heparin,Unfractionated Heparin,Heparin, Sodium,Heparin, Unfractionated,alpha Heparin
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
D014018	Tissue Distribution	Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.	Distribution, Tissue,Distributions, Tissue,Tissue Distributions