Biomaterial Database

Lysosomal enzyme activities in parenchymal and nonparenchymal liver cells isolated from young, adult and old rats. 1976

D L Knook, and E C Sleyster

Parenchymal and nonparenchymal cells were isolated from the livers of female BN/BiRij rats, aged 3, 12, 24 and 30-35 months, by means of enzymatic techniques. About 70% of the cells in the nonparenchymal cell suspensions were endothelial cells and 25% were Kupffer cells. More than 90% of the isolated parenchymal, Kupffer and endothelial cells were viable as judged by trypan blue exclusion and ultrastructural appearance. The age-related changes in the specific activities of the lysosomal enzymes acid phosphatase, beta-galactosidase, cathepsin D and arylsulphatase B in parenchymal and nonparenchymal cells showed no correlated behavior. The most prominent change was observed for the cathepsin D activity in parenchymal cells, which nearly triples during the lifespan of the rat. A comparison of the activities obtained with homogenates of the whole liver and with parenchymal and nonparenchymal cells revealed that aging changes in lysosomal enzyme activities in homogenates should be carefully interpreted, since opposite patterns of change were often observed in the activities in parenchymal cells and in nonparenchymal cells.

UI	MeSH Term	Description	Entries
D007728	Kupffer Cells	Specialized phagocytic cells of the MONONUCLEAR PHAGOCYTE SYSTEM found on the luminal surface of the hepatic sinusoids. They filter bacteria and small foreign proteins out of the blood and dispose of worn out red blood cells.	Kupffer Cell,Cell, Kupffer,Cells, Kupffer
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
D008247	Lysosomes	A class of morphologically heterogeneous cytoplasmic particles in animal and plant tissues characterized by their content of hydrolytic enzymes and the structure-linked latency of these enzymes. The intracellular functions of lysosomes depend on their lytic potential. The single unit membrane of the lysosome acts as a barrier between the enzymes enclosed in the lysosome and the external substrate. The activity of the enzymes contained in lysosomes is limited or nil unless the vesicle in which they are enclosed is ruptured or undergoes MEMBRANE FUSION. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed).	Autolysosome,Autolysosomes,Lysosome
D011914	Rats, Inbred BN	An inbred strain of rat that is widely used in a variety of research areas such as the study of ASTHMA; CARCINOGENESIS; AGING; and LEUKEMIA.	Rats, Inbred Brown Norway,Rats, BN,BN Rat,BN Rat, Inbred,BN Rats,BN Rats, Inbred,Inbred BN Rat,Inbred BN Rats,Rat, BN,Rat, Inbred BN
D002403	Cathepsins	A group of lysosomal proteinases or endopeptidases found in aqueous extracts of a variety of animal tissues. They function optimally within an acidic pH range. The cathepsins occur as a variety of enzyme subtypes including SERINE PROTEASES; ASPARTIC PROTEINASES; and CYSTEINE PROTEASES.	Cathepsin
D002470	Cell Survival	The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.	Cell Viability,Cell Viabilities,Survival, Cell,Viabilities, Cell,Viability, Cell
D005260	Female		Females
D005696	Galactosidases	A family of galactoside hydrolases that hydrolyze compounds with an O-galactosyl linkage. EC 3.2.1.-.	Galactosidase
D000135	Acid Phosphatase	An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC 3.1.3.2.	Acid beta-Glycerophosphatase,Acid beta Glycerophosphatase
D000367	Age Factors	Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.	Age Reporting,Age Factor,Factor, Age,Factors, Age