Biomaterial Database

Presystemic and systemic intestinal metabolism of fenoterol in the conscious rat. 1985

A S Koster, and G A Hofman, and A C Frankhuijzen-Sierevogel, and J Noordhoek

The intestinal and liver first pass metabolism of fenoterol.HBr (Berotec, Partusisten) was investigated in the conscious rat. Fenoterol plasma concentrations (2-1000 ng/ml) were measured with a new HPLC determination using electrochemical detection. After intraduodenal administration, fenoterol was incompletely absorbed (47-66% not absorbed). Presystemic intestinal (EGpre) and liver (EH) extraction ratios, EGpre = 0.93 +/- 0.01, EH = 0.67 +/- 0.04, were calculated from AUC values after intraduodenal, intraportal, and iv administration. Saturation of intestinal and/or liver metabolism was checked by using three dose levels at different administration routes. Total systemic availability after intraduodenal administration ranged from 0.8 (10 mg/kg) to 1.2% (40 mg/kg). The contribution of the splanchnic region to the systemic clearance of fenoterol was assessed by measuring fenoterol and fenoterol-glucuronide concentrations in arterial and portal venous blood under steady state conditions. During iv infusion (30 micrograms fenoterol/min X kg), an intestinal extraction ratio of EG = 0.26 was observed. After iv administration of fenoterol (1 and 2 mg/kg), dose-dependent pharmacokinetics were observed. Doubling of the dose resulted in an increase of systemic clearance (Cl = 53.8 +/- 2.7 and 74.4 +/- 1.8 ml/min X kg) and distribution volume (Vss = 0.95 +/- 0.13 and 1.21 +/- 0.11 liters/kg); the mean residence time (17.9 +/- 2.4 and 16.3 +/- 1.4 min) and terminal half-life (45.8 +/- 5.5 and 46.8 +/- 2.8 min) were not changed.

UI	MeSH Term	Description	Entries
D007263	Infusions, Parenteral	The administration of liquid medication, nutrient, or other fluid through some other route than the alimentary canal, usually over minutes or hours, either by gravity flow or often by infusion pumping.	Intra-Abdominal Infusions,Intraperitoneal Infusions,Parenteral Infusions,Peritoneal Infusions,Infusion, Intra-Abdominal,Infusion, Intraperitoneal,Infusion, Parenteral,Infusion, Peritoneal,Infusions, Intra-Abdominal,Infusions, Intraperitoneal,Infusions, Peritoneal,Intra Abdominal Infusions,Intra-Abdominal Infusion,Intraperitoneal Infusion,Parenteral Infusion,Peritoneal Infusion
D007408	Intestinal Absorption	Uptake of substances through the lining of the INTESTINES.	Absorption, Intestinal
D007413	Intestinal Mucosa	Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI.	Intestinal Epithelium,Intestinal Glands,Epithelium, Intestinal,Gland, Intestinal,Glands, Intestinal,Intestinal Gland,Mucosa, Intestinal
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008297	Male		Males
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D011169	Portal Vein	A short thick vein formed by union of the superior mesenteric vein and the splenic vein.	Portal Veins,Vein, Portal,Veins, Portal
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
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response