We have investigated the mechanism responsible for the diffusive component of intestinal glucose absorption, the major route by which glucose is absorbed. In perfused rat jejunum in vivo, absorption was strongly inhibited by phloretin, an inhibitor of GLUT2. The GLUT2 level at the brush-border membrane increased some 2-fold when the luminal glucose concentration was changed from 0 to 100 mM. Th...

Introduction Maintenance of normal glucose homeostasis results from the precise orchestration ofthree processes: glucose absorption via the gut, production by the liver, and utilization by nearly all tissues in the body. In the fasting state, most ofglucose utilization is by brain and is independent of insulin. Glucose levels are maintained during a fast by the tightly regulated release of gluc...

BETZ, A. LORRIS, DAVID D. GILBOE, DAVID L. YUDILEVICH, AND LESTER R. DREWES. Kinefics of unidz’rechzal glucose fransport into the isoluted dog brain. Am. J. Physiol. 225(3): 586592* 1973.An indicator-dilution technique with 22Na as the intravascular marker was used to measure unidirectional transport of D-glucose6-3H from blood into the isolated dog brain. The rate of unidirectional glucose tra...

possess a transport system for glucose of the facilitative diffusion type; these transporters allow the movement of glucose across the plasma membrane down its chemical gradient either into or out of cells. These transporters are specific for the D-enantiomer of glucose and are not coupled to any energy-requiring components, such as ATP hydrolysis or a HI gradient [1]. The facilitative glucose ...

Hydrogen peroxide sensing microelectrodes for scanning electrochemical microscopy (SECM) have been developed and used to measure hydrogen peroxide in the diffusion layer during electrochemical reduction of oxygen on gold and carbon electrodes. These microelectrode biosensors were also used to detect immobilized glucose oxidase through the production of hydrogen peroxide during enzymatic oxidati...

Methods were developed for the in vivo estimation of rate constants for transport from blood to aqueous and subsequently into lens and corneal water compartments. Glucose transport was characterized with the nonmetabolized radiolabeled glucose analogs (14C)-L-glucose (L-glu) and (3H)-3-O-methyl-D-glucose (mD-glu) that are considered to enter the ocular humors by passive and facilitated diffusio...

Determination of the rates of diffusion of beta-lactam antibiotics through purified Pseudomonas aeruginosa porins C, D2, and E in liposomes yielded the following results. (i) The rates of carbapenem (imipenem and meropenem) diffusion through the protein D2 pore were roughly 2 to 70 times higher than those through other porin pores. It is not clear why the protein D2 pore allowed rapid diffusion...

The kinetic parameters of glucose transport in four Crabtree-positive and four Crabtree-negative yeasts were determined. The organisms were grown in aerobic glucose-limited chemostats at a dilution rate of 0.1 h-1. The results show a clear correlation between the presence of high-affinity glucose transport systems and the absence of aerobic fermentation upon addition of excess glucose to steady...

Peritoneal dysfunction is a major factor leading to treatment failure of peritoneal dialysis (PD). However, the precise mechanism of the peritoneal diffusion changes related to PD remains to be elucidated. To this end, we have established a novel peritoneal diffusion model in vitro, which consists of a three-dimensional culture system using a collagen vitrigel membrane chamber and a fluid-strea...