The type IIa sodium-dependent phosphate cotransporter (Npt2a) plays a critical role in reabsorption of inorganic phosphate (Pi) by renal proximal tubular cells. Pi abnormalities during early stages of sepsis have been reported, but the mechanisms regulating Pi homeostasis during acute inflammation are poorly understood. We examined the regulation of Pi metabolism and renal Npt2a expression duri...

A possible role for GLUT2 transiently expressed in the rat jejunal brush-border membrane (BBM) under the influence of glucagon-like peptide 2 (GLP-2) was investigated using in vivo perfusion of the intestinal lumen as well as isolation of membrane proteins and immunohistochemistry. A 1 h vascular infusion of GLP-2 in vivo doubled the rate of fructose absorption and this increase could be blocke...

Brush border myosin-I (BBM-I) is a single-headed myosin found in the microvilli of intestinal epithelial cells, where it forms lateral bridges connecting the core bundle of actin filaments to the plasma membrane. Extending previous observations (Jontes, J.D., E.M. Wilson-Kubalek, and R.A. Milligan. 1995. Nature [Lond.]. 378:751-753), we have used cryoelectron microscopy and helical image analys...

With the proliferation of mobile devices, mobile learning has become a learning paradigm in education. The aim of this paper is to evaluate the media richness of various message delivery methods in mobile learning (m-learning) environment. This study evaluates media richness in respect to content timeliness, content richness, content accuracy and content adaptability in WhatsApp, Email, SMS, Tw...

The effect of 1, 3 and 5-day fasting was studied on serum parameters; enzymes of brush border membrane and carbohydrate metabolism; transport of Pi and proline in different parts of the rat kidney. Fasting decreased the activities of lactate dehydrogenase, malate dehydrogenase but increased the activities of glucose-6-phosphatase and fructose 1,6-bisphosphatase; glucose-6-phosphate dehydrogenas...

The transport of Fe(2+) and other divalent transition metal ions across the intestinal brush border membrane (BBM) was investigated using brush border membrane vesicles (BBMVs) as a model. This transport is an energy-independent, protein-mediated process. The divalent metal ion transporter of the BBM is a spanning protein, very likely a protein channel, that senses the phase transition of the B...

In the mammalian small intestine, coupled NaCl absorption occurs via the dual operation of Na/H and Cl/HCO(3) exchange on the villus cell brush border membrane (BBM). Although constitutive nitric oxide (cNO) has been demonstrated to alter gastrointestinal tract functions, how cNO may specifically alter these two transporters to regulate coupled NaCl absorption is unknown. In villus cells, inhib...

Brush border myosin-I (BBM-I) is a single-headed unconventional myosin found in the microvilli of intestinal epithelial cells. We used stopped-flow kinetic analysis to measure the rate and equilibrium constants for several steps in the BBM-I ATPase cycle. We determined the rates for ATP binding to BBM-I and brush border actomyosin-I (actoBBM-I), the rate of actoBBM-I dissociation by ATP, and th...

Numerous studies have demonstrated various structure/function correlations at the level of transport proteins in the kidney cell membranes and various intracellular organelles. However, characterization of the lipid phase of these membranes is rare. Here, we report the differences in lipid organization and dynamics of the brush-border membranes (BBM), basolateral membranes (BLM) and endocytotic...

Glutamine, the primary metabolic fuel for the mammalian small intestinal enterocytes, is primarily assimilated by Na-amino acid cotransporters. Although Na-solute cotransport has been shown to exist in the brush border membrane (BBM) of the absorptive villus cells, the identity of Na-glutamine cotransport in rabbit small intestinal villus cells was unknown. Na-dependent glutamine uptake is pres...