Biomaterial Database

Decreased activity and expression of intestinal oligopeptide transporter PEPT1 in rats with hyperthyroidism in vivo. 2004

Kayoko Ashida, and Toshiya Katsura, and Hideyuki Saito, and Ken-ichi Inui

Department of Pharmacy, Kyoto University Hospital, Faculty of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8507, Japan.

OBJECTIVE To examine the effect of thyroid hormone status on PEPT1 in vivo, the activity and expression of PEPT1 in the small intestine were examined in euthyroid and hyperthyroid rats. METHODS Hyperthyroidism was induced by treating rats with L-thyroxine (12 mg/L) in the drinking water for 21 days. Transport activity was measured by everted small intestinal preparations and in situ intestinal loop technique. Expressions of PEPT1 mRNA and protein were evaluated by competitive polymerase chain reaction and Western blotting, respectively. RESULTS The uptake of [14C]glycylsarcosine by everted small intestinal preparations was significantly decreased in hyperthyroid rats, whereas that of methyl-alpha-D-[14C(U)]-glucopyranoside was not altered. Kinetic analysis showed that the Vmax value for [14C]glycylsarcosine uptake was significantly decreased in hyperthyroid rats, whereas the Km value was not affected. The mean portal vein concentrations after intrajejunal administration of [14C]glycylsarcosine were also decreased in hyperthyroid rats. Moreover, hyperthyroidism caused a significant decrease in the expression of PEPT1 mRNA in the small intestine, whereas the expression of Na+/glucose cotransporter (SGLT1) mRNA was not changed. The level of PEPT1 protein was also decreased in the small intestine of hyperthyroid rats. CONCLUSIONS These results indicate that in hyperthyroid rats, the activity and expression of PEPT1 were decreased in the small intestine.

UI	MeSH Term	Description	Entries
D006980	Hyperthyroidism	Hypersecretion of THYROID HORMONES from the THYROID GLAND. Elevated levels of thyroid hormones increase BASAL METABOLIC RATE.	Hyperthyroid,Primary Hyperthyroidism,Hyperthyroidism, Primary,Hyperthyroids
D007564	Japan	A country in eastern Asia, island chain between the North Pacific Ocean and the Sea of Japan, east of the Korean Peninsula. The capital is Tokyo.	Bonin Islands
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
D008562	Membrane Glycoproteins	Glycoproteins found on the membrane or surface of cells.	Cell Surface Glycoproteins,Surface Glycoproteins,Cell Surface Glycoprotein,Membrane Glycoprotein,Surface Glycoprotein,Glycoprotein, Cell Surface,Glycoprotein, Membrane,Glycoprotein, Surface,Glycoproteins, Cell Surface,Glycoproteins, Membrane,Glycoproteins, Surface,Surface Glycoprotein, Cell,Surface Glycoproteins, Cell
D008757	Methylglucosides		Methylglucopyranosides
D009004	Monosaccharide Transport Proteins	A large group of membrane transport proteins that shuttle MONOSACCHARIDES across CELL MEMBRANES.	Hexose Transport Proteins,Band 4.5 Preactin,Erythrocyte Band 4.5 Protein,Glucose Transport-Inducing Protein,Hexose Transporter,4.5 Preactin, Band,Glucose Transport Inducing Protein,Preactin, Band 4.5,Proteins, Monosaccharide Transport,Transport Proteins, Hexose,Transport Proteins, Monosaccharide,Transport-Inducing Protein, Glucose
D011169	Portal Vein	A short thick vein formed by union of the superior mesenteric vein and the splenic vein.	Portal Veins,Vein, Portal,Veins, Portal
D002250	Carbon Radioisotopes	Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.	Radioisotopes, Carbon
D004151	Dipeptides	Peptides composed of two amino acid units.	Dipeptide
D004195	Disease Models, Animal	Naturally-occurring or experimentally-induced animal diseases with pathological processes analogous to human diseases.	Animal Disease Model,Animal Disease Models,Disease Model, Animal