The transcription factor, tonicity-responsive enhancer binding protein (TonEBP), is involved in the adaptive response against hypertonicity. TonEBP regulates the expression of genes that catalyze the accumulation of osmolytes, and its transcriptional activity is increased by hypertonicity. The goal of the present investigation was to investigate whether cell shrinkage or high intracellular ioni...

The mechanisms of fluid and solute abnormalities that should be considered in any patient with severe hyperglycemia include changes in the total amount of extracellular solute, osmotic diuresis, intake of water driven by thirst, and influences from associated conditions. The absence of osmotic diuresis distinguishes dialysis-associated hyperglycemia (DH) from hyperglycemia with preserved renal ...

Small volume hypertonic resuscitation is a relatively new conceptual approach to shock therapy. It was originally based on the idea that a relatively large blood volume expansion could be obtained by administering a relatively small volume of fluid, taking advantage of osmosis. It was soon realized that the physiological vasodilator property of hypertonicity was a useful byproduct of small volu...

Hypertonicity has pleiotropic effects on cell function, including activation of transporters and regulation of gene expression. It is important to investigate the action of hypertonicity on cystic fibrosis gene expression because cystic fibrosis transmembrane conductance regulator (CFTR), the cAMP-regulated Cl(-) channel, regulates ion transport across the secretory epithelia, which are often i...

The effect of hypertonicity on the electrical properties of vertebrate myocardial cells was studied in ventricular muscle fibers of guinea pig, cat, frog, and chicken. The latter two species do not have a T-tubule system, whereas the former two do. In hypertonic solutions (2 x isotonic) produced by addition of sucrose or excess of NaCl, cell diameter decreased and there was a slight hyperpolari...

Aquaporin 1 (AQP1) is the major water channel in the renal proximal tubule (PT) and thin descending limb of Henle, but its regulation remains elusive. Here, we investigated the effect of ANG II, a key mediator of body water homeostasis, on AQP1 expression in immortalized rat proximal tubule cells (IRPTC) and rat kidney. Real-time PCR on IRPTC exposed to ANG II for 12 h revealed a biphasic effec...

Assessed 48 infants of HIV-positive and HIV-negative mothers on the Brazelton Neonatal Behavioral Assessment Scale. Infants exposed to HIV-positive mothers were disadvantaged from birth due to their mothers having obstetric complications and to the infants having orienting problems and abnormal reflexes on the Brazelton Newborn Scale. These problems may be early precursors of the later visual-s...

ANGIOCARDIOGRAPHY and cineangiocardiography are employed with increasing frequency for the diagnosis of cardiovascular diseases. These commonplace technics of cardiovascular radiology depend upon the rapid injection of radiopaque materials into the heart or central circulation. A wide variety of substances are in use, but all are hypertonic and some are considerably more viscous than blood. A v...

Estrogen increases baseline transepithelial permeability across CaSki cultures and augments the increase in permeability in response to hypertonic gradients. In estrogen-treated cells, lowering cytosolic calcium abrogated the hypertonicity-induced augmented increase in permeability and decreased baseline permeability to a greater degree than in estrogen-deprived cells. Steady-state levels of cy...

We reported that the multiple PDZ protein 1 (MUPP1) is an osmotic response protein in kidney cells. This up-regulation was found to be necessary for the maintenance of tight epithelial properties in these cells. We investigated whether an interaction with one or more members of the claudin family is responsible for this observation. In response to hypertonicity, the up-regulation of claudin-4 (...