Biomaterial Database

Plasma retinol transport and clearance in hypervitaminosis A. 1979

S Donoghue, and D S Kronfeld, and C F Ramberg

Effects of mild and severe hypervitaminosis A on retinol transport and clearance were studied in mature ewes. Excessive vitamin A intake was assoicated with high concentrations of vitamin A in plasma and liver, with elevated serum enzymes, with decreased feed consumption and packed cell volume, and with epithelial hyperplasia. Retinol transport in plasma increased 6- to 8-fold with excessive dietary vitamin A, was greater with mild hypervitaminosis A, and increased exponentially with vitamin A concentration in plasma. Clearance of retinol from plasma increased 2-fold with hypervitaminosis A, exhibited a greater response in the mild group, and increased linearly with vitamin A concentration in plasma. The relationship of clearance to vitamin A concentration in liver was described best by a power function. Retinol clearance represents a mechanism to maintain vitamin A concentration in plasma and may be most effective below vitamin A concentrations of 135 microgram/dl plasma. With severe hypervitaminosis A, massive vitamin A accumulates in liver leading to hepatic dysfunction and a resultant decrease in retinol clearance from plasma.

UI	MeSH Term	Description	Entries
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
D009929	Organ Size	The measurement of an organ in volume, mass, or heaviness.	Organ Volume,Organ Weight,Size, Organ,Weight, Organ
D004032	Diet	Regular course of eating and drinking adopted by a person or animal.	Diets
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
D005260	Female		Females
D006400	Hematocrit	The volume of packed RED BLOOD CELLS in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, ANEMIA shows a low value; POLYCYTHEMIA, a high value.	Erythrocyte Volume, Packed,Packed Red-Cell Volume,Erythrocyte Volumes, Packed,Hematocrits,Packed Erythrocyte Volume,Packed Erythrocyte Volumes,Packed Red Cell Volume,Packed Red-Cell Volumes,Red-Cell Volume, Packed,Red-Cell Volumes, Packed,Volume, Packed Erythrocyte,Volume, Packed Red-Cell,Volumes, Packed Erythrocyte,Volumes, Packed Red-Cell
D000410	Alanine Transaminase	An enzyme that catalyzes the conversion of L-alanine and 2-oxoglutarate to pyruvate and L-glutamate. (From Enzyme Nomenclature, 1992) EC 2.6.1.2.	Alanine Aminotransferase,Glutamic-Pyruvic Transaminase,SGPT,Alanine-2-Oxoglutarate Aminotransferase,Glutamic-Alanine Transaminase,Alanine 2 Oxoglutarate Aminotransferase,Aminotransferase, Alanine,Aminotransferase, Alanine-2-Oxoglutarate,Glutamic Alanine Transaminase,Glutamic Pyruvic Transaminase,Transaminase, Alanine,Transaminase, Glutamic-Alanine,Transaminase, Glutamic-Pyruvic
D000469	Alkaline Phosphatase	An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC 3.1.3.1.
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
D001219	Aspartate Aminotransferases	Enzymes of the transferase class that catalyze the conversion of L-aspartate and 2-ketoglutarate to oxaloacetate and L-glutamate. EC 2.6.1.1.	Aspartate Aminotransferase,Aspartate Transaminase,Glutamic-Oxaloacetic Transaminase,SGOT,Aspartate Apoaminotransferase,Glutamate-Aspartate Transaminase,L-Aspartate-2-Oxoglutarate Aminotransferase,Serum Glutamic-Oxaloacetic Transaminase,Aminotransferase, Aspartate,Aminotransferase, L-Aspartate-2-Oxoglutarate,Aminotransferases, Aspartate,Apoaminotransferase, Aspartate,Glutamate Aspartate Transaminase,Glutamic Oxaloacetic Transaminase,Glutamic-Oxaloacetic Transaminase, Serum,L Aspartate 2 Oxoglutarate Aminotransferase,Serum Glutamic Oxaloacetic Transaminase,Transaminase, Aspartate,Transaminase, Glutamate-Aspartate,Transaminase, Glutamic-Oxaloacetic,Transaminase, Serum Glutamic-Oxaloacetic