Biomaterial Database

Uptake of 5-methyltetrahydrofolic acid by the rat jejunum. 1975

J A Blair, and A J Matty, and A Razzaque

1. Everted sacs of rat jejunum were used to study the transport of 5-methyltetrahydrofolic acid at various concentrations and at different pHs. 2. The transport of 5-methyltetrahydrofolic acid appeared to be linear with increasing incubation time at a 5-methyltetrahydrofolic acid concentration of 10(-5) M in the incubating medium. Tissue uptake was much higher than serosal uptake. 3. At 'zero' concentration gradient of 5-methyltetrahydrofolic acid, the transport from mucosal to serosal sides was negligible but tissue uptake was appreciable. 4. Reducing the incubation temperature from 37 to 27 degrees C gave a Q10 value of 1-8. 5. The characteristics of 5-methyltetrahydrofolic acid uptake suggested a non-saturable transport mechanism. 6. Studies were also carried out with isolated mucosal epithelial cells at different incubation times and at different pH values. 7. The over-all results suggest that 5-methyltetrahydrofolic acid transport is most likely a passive diffusion of its zwitterion and also a solvent drag with water flow. 8. The 5-methyltetrahydrofolic acid may be converted to its zwitterion in an acid microclimate at the surface of the intestinal absorbing cell.

UI	MeSH Term	Description	Entries
D007413	Intestinal Mucosa	Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI.	Intestinal Epithelium,Intestinal Glands,Epithelium, Intestinal,Gland, Intestinal,Glands, Intestinal,Intestinal Gland,Mucosa, 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
D008297	Male		Males
D004847	Epithelial Cells	Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.	Adenomatous Epithelial Cells,Columnar Glandular Epithelial Cells,Cuboidal Glandular Epithelial Cells,Glandular Epithelial Cells,Squamous Cells,Squamous Epithelial Cells,Transitional Epithelial Cells,Adenomatous Epithelial Cell,Cell, Adenomatous Epithelial,Cell, Epithelial,Cell, Glandular Epithelial,Cell, Squamous,Cell, Squamous Epithelial,Cell, Transitional Epithelial,Cells, Adenomatous Epithelial,Cells, Epithelial,Cells, Glandular Epithelial,Cells, Squamous,Cells, Squamous Epithelial,Cells, Transitional Epithelial,Epithelial Cell,Epithelial Cell, Adenomatous,Epithelial Cell, Glandular,Epithelial Cell, Squamous,Epithelial Cell, Transitional,Epithelial Cells, Adenomatous,Epithelial Cells, Glandular,Epithelial Cells, Squamous,Epithelial Cells, Transitional,Glandular Epithelial Cell,Squamous Cell,Squamous Epithelial Cell,Transitional Epithelial Cell
D004848	Epithelium	The layers of EPITHELIAL CELLS which cover the inner and outer surfaces of the cutaneous, mucus, and serous tissues and glands of the body.	Mesothelium,Epithelial Tissue,Mesothelial Tissue,Epithelial Tissues,Mesothelial Tissues,Tissue, Epithelial,Tissue, Mesothelial,Tissues, Epithelial,Tissues, Mesothelial
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
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
D001692	Biological Transport	The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.	Transport, Biological,Biologic Transport,Transport, Biologic
D012704	Serous Membrane	A thin lining of closed cavities of the body, consisting of a single layer of squamous epithelial cells (MESOTHELIUM) resting on a thin layer of CONNECTIVE TISSUE, and covered with secreted clear fluid from blood and lymph vessels. Major serous membranes in the body include PERICARDIUM; PERITONEUM; and PLEURA.	Serosa,Serous Membranes,Membrane, Serous,Membranes, Serous
D013696	Temperature	The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.	Temperatures