Biomaterial Database

Uncontrolled adipocyte proliferation is not the primary lesion in the genetically-obese Zucker rat. 1981

P R Johnson, and A L Goldstein

One of several hypotheses concerning the nature of the genetic lesion which produces obesity in the Zucker fatty rat is that a defect in control of cellular proliferation in adipose tissue leads to hypercellular-hypertrophic obesity with all its metabolic and behavioral sequalae. Three lines of evidence are presented which render this hypothesis untenable: (1) maximal cell enlargement precedes maximum rate of cell addition in adipose tissue; (2) lipectomized obese rats do not regenerate subcutaneous adipocytes; and (3) cultured adipocyte precursors from obese rat adipose tissue grow at the same rate as do cells cultured from lean tissue. An alternative hypothesis that an alteration in hepatic lipid metabolism may be the locus of the genetic lesion is presented along with evidence from in-vivo and in-vitro studies of hepatic lipogenesis in the Zucker rat.

UI	MeSH Term	Description	Entries
D006984	Hypertrophy	General increase in bulk of a part or organ due to CELL ENLARGEMENT and accumulation of FLUIDS AND SECRETIONS, not due to tumor formation, nor to an increase in the number of cells (HYPERPLASIA).	Hypertrophies
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).
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
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D000273	Adipose Tissue	Specialized connective tissue composed of fat cells (ADIPOCYTES). It is the site of stored FATS, usually in the form of TRIGLYCERIDES. In mammals, there are two types of adipose tissue, the WHITE FAT and the BROWN FAT. Their relative distributions vary in different species with most adipose tissue being white.	Fatty Tissue,Body Fat,Fat Pad,Fat Pads,Pad, Fat,Pads, Fat,Tissue, Adipose,Tissue, Fatty
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
D050356	Lipid Metabolism	Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.	Metabolism, Lipid
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
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In