Botulinum neurotoxin is the most potent poison known worldwide. Over past two centuries, its structure and functions have been studied in detail, obtained pure form. Knowledge of mechanisms action botulinum has determined directions possible use: negative, as a biological (toxin) weapon, positive, an agent that eliminates pathological muscle hypertonicity neuropathic pain can be used for aesthe...

WATER is the most abundant molecule of the body, around 60% by weight. Volume and composition of cellular water, also known as internal milieu, are critical factors that affect cellular function because cellular water is the medium in which the majority of biochemical reactions take place. How cells adapt to hypertonic environment is an important subject that has been studied for a long time. T...

This study examined the effects of hypohydration on thermoregulation during cold exposure. In addition, the independent influences of hypohydration-associated hypertonicity and hypovolemia were investigated. Nine male volunteers were monitored for 30 min at 25 degrees C, then for 120 min at 7 degrees C, under three counterbalanced conditions: euhydration (Eu), hypertonic hypohydration (HH), and...

Immune cells rely on the transcription factor NFAT5 to adapt to hypertonic stress. The hypertonicity-dependent role of NFAT5 in T cells in vivo remains unclear because mouse models of NFAT5 deficiency have produced substantially different T cell phenotypes. In this study, we analyzed the T cell compartment in NFAT5-null and T cell-specific NFAT5 knockout mice. We found that NFAT5-null mice had ...

We were interested whether PKCα, δ, ε or ζ is the isoform actually employed in the activation of hypertonicity-induced cation channels (HICCs) in primary cultures of rat hepatocytes. Quantitative SDS-page and Western-blot experiments revealed that PKCα, δ and ε were stimulated by Indolactam V (as a DAG substitute for activation of c and nPKCs) but that only PKCδ and ε did respond to hypertonic ...

Somponpun, Suwit J., Alan Kim Johnson, Terry Beltz, and Celia D. Sladek. Estrogen receptorexpression in osmosensitive elements of the lamina terminalis: regulation by hypertonicity. Am J Physiol Regul Integr Comp Physiol 287: R661–R669, 2004. First published May 13, 2004; 10.1152/ajpregu.00136.2004.—The subfornical organ (SFO), median preoptic nucleus (MnPO), and organum vasculosum lamina termi...

The exposure of 3T3 cells to a medium made hypertonic by the addition of NaCl induced activation of a heat-shock transcription factor (HSF). This activation, as monitored by gel-mobility-shift assays, occurred within 10 min of hypertonic shock and was dose-dependent in relation to the osmotic strength of the medium up to 0.7 osM. Competition analysis indicated that the effect of hypertonic shoc...

In adults, hyperosmolality stimulates central osmoreceptors, resulting in arginine vasopressin (AVP) secretion. Near-term fetal sheep have also developed mechanisms to respond to intravascular hypertonicity with stimulation of in utero AVP release. However, prior studies demonstrating fetal AVP secretion have utilized plasma tonicity changes greater than those required for adult osmotically ind...

BACKGROUND Hypertonicity can perturb cellular functions, induce DNA damage-like responses and inhibit proliferation. The transcription factor NFAT5 induces osmoprotective gene products that allow cells to adapt to sustained hypertonic conditions. Although it is known that NFAT5-deficient lymphocytes and renal medullary cells have reduced proliferative capacity and viability under hypertonic str...

Our previous studies have documented MAPK mediation of the hypertonicity-induced stimulation of COX-2 expression in cultured renal medullary epithelial cells. The present study extends this observation by examining the role of reactive oxygen species (ROSs). ROS levels, determined using dichlorodihydrofluorescence diacetate and cytochrome c, were rapidly and significantly increased following ex...