Biomaterial Database

Insulin binding and removal by livers of genetically obese rats. 1983

C Karakash, and B Jeanrenaud

Livers from 9-10-wk-old genetically obese and hyperinsulinemic (fa/fa) rats contained more DNA, proteins, and lipids than livers of age-matched controls. Actually, the increase in liver mass of fa/fa rats was mainly due to an increased cell number. On perfusion with insulin (1.75-16 nM), livers of obese fa/fa rats removed 35-40% less insulin per gram tissue than control livers. When calculated on a per organ basis, removal capacity was, however, similar in livers of control and obese fa/fa rats. The binding of 125I-insulin to as well as the insulin removal by isolated hepatocytes was also assessed. Contrary to previous unexpected data in which the downregulation of insulin receptors by hyperinsulinemia was reported not to prevail in hepatocytes from obese fa/fa rats, it was found that the binding capacity of hepatocytes from fa/fa rats was decreased by 45% without alteration of the binding affinity. Moreover, in hepatocytes from obese fa/fa rats, both binding and removal of insulin were lowered to an analogous extent. It is concluded that livers of obese fa/fa rats behave, with regard to insulin binding and removal, as those of other hyperinsulinemic obese animals.

UI	MeSH Term	Description	Entries
D007328	Insulin	A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1).	Iletin,Insulin A Chain,Insulin B Chain,Insulin, Regular,Novolin,Sodium Insulin,Soluble Insulin,Chain, Insulin B,Insulin, Sodium,Insulin, Soluble,Regular Insulin
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
D009765	Obesity	A status with BODY WEIGHT that is grossly above the recommended standards, usually due to accumulation of excess FATS in the body. The standards may vary with age, sex, genetic or cultural background. In the BODY MASS INDEX, a BMI greater than 30.0 kg/m2 is considered obese, and a BMI greater than 40.0 kg/m2 is considered morbidly obese (MORBID OBESITY).
D009929	Organ Size	The measurement of an organ in volume, mass, or heaviness.	Organ Volume,Organ Weight,Size, Organ,Weight, Organ
D010477	Perfusion	Treatment process involving the injection of fluid into an organ or tissue.	Perfusions
D011924	Rats, Zucker	Two populations of Zucker rats have been cited in research--the "fatty" or obese and the lean. The "fatty" rat (Rattus norvegicus) appeared as a spontaneous mutant. The obese condition appears to be due to a single recessive gene.	Zucker Rat,Zucker Rats,Rat, Zucker
D011972	Receptor, Insulin	A cell surface receptor for INSULIN. It comprises a tetramer of two alpha and two beta subunits which are derived from cleavage of a single precursor protein. The receptor contains an intrinsic TYROSINE KINASE domain that is located within the beta subunit. Activation of the receptor by INSULIN results in numerous metabolic changes including increased uptake of GLUCOSE into the liver, muscle, and ADIPOSE TISSUE.	Insulin Receptor,Insulin Receptor Protein-Tyrosine Kinase,Insulin Receptor alpha Subunit,Insulin Receptor beta Subunit,Insulin Receptor alpha Chain,Insulin Receptor beta Chain,Insulin-Dependent Tyrosine Protein Kinase,Receptors, Insulin,Insulin Receptor Protein Tyrosine Kinase,Insulin Receptors
D005260	Female		Females
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
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus