A light-dependent mechanism that results in a slow, high-amplitude swelling of spinach chloroplasts in vitro has been discovered. The swelling is readily observed by optical and gravimetric methods, and by the use of an electronic particle counter; all show a 100 per cent increase of chloroplast volume in the light with an approximately 10-minute half-time. The existence of an osmotic mechanism...

The effect of osmotic stress on wheat (Triticum aestivum L.) mitochondrial activity and phospholipid composition was investigated. Preliminary growth measurements showed that osmotic stress (-0.25 or -0.5 megapascal external water potential) inhibited the rate of shoot dry matter accumulation while root dry matter accumulation was less sensitive. We have determined that differences in sensitivi...

Cells swell in response a hypoosmotic challenge. By converting osmotic pressure to hydrostatic pressure at the cell membrane via van't Hoff's law, and converting that to tension via Laplace's law one predicts that the cell membrane should stretch and become stiff. We tested this prediction using the atomic force microscopy. During osmotic swelling cells did not become stiff and generally became...

The ocular characteristics and responses were examined in patients who had undergone extracapsular cataract extraction (ECCE), intracapsular cataract extraction (ICCE) and penetrating keratoplasty (PKP) in one eye only. In each of the three groups, corneal sensitivity (the inverse of corneal touch threshold), oxygen uptake rate, and endothelial cell density were lower in the operated eye than i...

The hypothesis that cellular hypertrophy in congestive heart failure (CHF) modulates mechanosensitive (ie, swelling- or stretch-activated) anion channels was tested. Digital video microscopy and amphotericin-perforated-patch voltage clamp were used to measure cell volume and ion currents in ventricular myocytes isolated from normal dogs and dogs with rapid ventricular pacing-induced CHF. In nor...

Lee, Wing-Kee, and Frank Thévenod. A role for mitochondrial aquaporins in cellular life-and-death decisions? Am J Physiol Cell Physiol 291: C195–C202, 2006; doi:10.1152/ajpcell.00641.2005.—Mitochondria dominate the process of life-and-death decisions of the cell. Continuous generation of ATP is essential for cell sustenance, but, on the other hand, mitochondria play a central role in the orches...

INTRODUCTION accounted for by the uptake of Cal+ and accompanying anions (17) . The swelling of isolated mitochondria in response to the introduction of orthophosphate (Pi) to the suspending medium has been studied in a number of works (1-15) . In particular, Packer (11) found the P ; induced swelling to be dependent on the presence of state 4 and to be reversed upon the induction of state 3 . ...

The osmotic tissue expander is a new device made of a hydrogel expanding skin that does not require external fillings. Once implanted, it absorbs body fluids, which leads to a gradual swelling of the device. The swelling phase is completed in 6 to 8 weeks and results in skin gain. Different shapes and sizes are available, and the devices can be used in almost every area of the body. Over a 4-ye...

The glucocorticoid triamcinolone acetonide is clinically used for the treatment of macular edema. However, the edema-resolving mechanisms of triamcinolone are incompletely understood. Since cell swelling is a central cause of cytotoxic edema in the brain and retina, we determined the effects of triamcinolone acetonide on the swelling of retinal ganglion and Müller glial cells in acutely isolate...