Biomaterial Database

Effect of lactose on phosphate transport into rat intestinal brush border membrane vesicles. 1985

H Debiec, and R Lorenc

Brush border membrane vesicles (BBMV) were used to evaluate the influence of lactose on phosphate (Pi) transport in the intestine of the rat. BBMV were prepared from duodenum, jejunum and ileum of 3-, 4- and 7-wk-old rats. Na+-dependent active transport of Pi was investigated in the presence of an Na+ gradient; Na+-independent, diffusional transport was investigated by substitution of choline chloride for NaCl. In 3-wk-old rats active Pi transport dominated, whereas in 4-wk-old rats a decrease in active transport and an increase of the diffusional component of total Pi transport were observed. Furthermore, in 7-wk-old rats, Pi was transported by simple diffusion alone. Addition of lactose to the preincubation medium had no effect on Pi transport in duodenal and jejunal BBMV isolated from 3-wk-old rats. In the remaining BBMV preparations, lactose caused a twofold enhancement of diffusional Pi uptake. Glucose and galactose had no effect on diffusional Pi uptake into BBMV. These results indicate that lactose may directly interact with luminal membranes, thus leading to increased diffusional transport. The membranes with a decreased Na+-dependent Pi transport activity are most susceptible to the influence of lactose.

UI	MeSH Term	Description	Entries
D007408	Intestinal Absorption	Uptake of substances through the lining of the INTESTINES.	Absorption, Intestinal
D007583	Jejunum	The middle portion of the SMALL INTESTINE, between DUODENUM and ILEUM. It represents about 2/5 of the remaining portion of the small intestine below duodenum.	Jejunums
D007785	Lactose	A disaccharide of GLUCOSE and GALACTOSE in human and cow milk. It is used in pharmacy for tablets, in medicine as a nutrient, and in industry.	Anhydrous Lactose,Lactose, Anhydrous
D008297	Male		Males
D008871	Microvilli	Minute projections of cell membranes which greatly increase the surface area of the cell.	Brush Border,Striated Border,Border, Brush,Border, Striated,Borders, Brush,Borders, Striated,Brush Borders,Microvillus,Striated Borders
D010710	Phosphates	Inorganic salts of phosphoric acid.	Inorganic Phosphate,Phosphates, Inorganic,Inorganic Phosphates,Orthophosphate,Phosphate,Phosphate, Inorganic
D005690	Galactose	An aldohexose that occurs naturally in the D-form in lactose, cerebrosides, gangliosides, and mucoproteins. Deficiency of galactosyl-1-phosphate uridyltransferase (GALACTOSE-1-PHOSPHATE URIDYL-TRANSFERASE DEFICIENCY DISEASE) causes an error in galactose metabolism called GALACTOSEMIA, resulting in elevations of galactose in the blood.	D-Galactose,Galactopyranose,Galactopyranoside,D Galactose
D005947	Glucose	A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.	Dextrose,Anhydrous Dextrose,D-Glucose,Glucose Monohydrate,Glucose, (DL)-Isomer,Glucose, (alpha-D)-Isomer,Glucose, (beta-D)-Isomer,D Glucose,Dextrose, Anhydrous,Monohydrate, Glucose
D000375	Aging	The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.	Senescence,Aging, Biological,Biological Aging
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