... gradually returned to initial values. However, pH reached its peak value following 1 week at −20°C, but decreased after longer periods of freezing. During cold acclimation, cholesterol levels decreased in the hemolymph and the membrane fraction of fat body but not in other tissues. Lethal freezing at −80°C...

... are required by the crustaceans to form the membrane component cholesterol, which in turn plays a role in thermal adaptation. Here, we determined the influence of temperature on growth,reproduction and the allocation of dietary sterol into somatic tissues and eggs of the keystone species Daphnia magna raised...

...R. Patrick Hassett; Elizabeth L. Crockett SUMMARY Effects of habitat and acclimation temperature on cholesterol contents were examined in oceanic and inshore species of copepods. The cholesterol content of five species of thermally acclimated copepods was determined, and nine species (representing...

...John K. Zehmer; Jeffrey R. Hazel SUMMARY In poikilotherms, increases in plasma membrane (PM) cholesterol and an increase in the degree of lipid acyl chain saturation commonly accompany an increase in growth temperature. This has typically been interpreted in terms of membrane fluidity/order...

... for 40 days at -20°C, individual organ function was retained to a limited extent. Through the autumn, cholesterol concentrations in the hemolymph increased nearly fourfold. In contrast, the ratio of cholesterol to protein content (nmol mg l -1 ) in the MT membrane remained relatively constant (22∼24 nmol...

...- 6) as well as high levels of cholesterol. These results are discussed in relation to neurological function and the emerging field of membrane lipid rafts. Body mass and brain mass of the mice, rats and all the bird species were obtained immediately following death. For sheep and cattle, carcass...

...), the skin supported only a very small flux of NH 3 (0.0095 μmol cm -2 min -1 ). Cholesterol content (4.5 μmol g -1 ) in the skin was high, which suggests low membrane fluidity. Phosphatidylcholine, which has a stabilizing effect on membranes, constituted almost 50% of the skin phospholipids...

...John K. Zehmer; Jeffrey R. Hazel SUMMARY Rafts are cholesterol- and sphingolipid-enriched microdomains of the plasma membrane (PM) that organize many signal transduction pathways. Interactions between cholesterol and saturated lipids lead to patches of liquid-ordered membrane (rafts) phase...

..., coincident with the onset of breathing. The DSP/PL ratio increased after pipping, whereas cholesterol levels (Chol) increased prior to pipping. This resulted in a decrease in the Chol/PL and Chol/DSP ratios after pipping. Thus, TTF-1 and SP-B appear to be highly conserved within the vertebrates. Maturation...

...Marie V. St-Pierre; Gerd A. Kullak-Ublick; Bruno Hagenbuch; Peter J. Meier ABSTRACT Bile acids are steroidal amphipathic molecules derived from the catabolism of cholesterol. They modulate bile flow and lipid secretion, are essential for the absorption of dietary fats and vitamins, and have been...

... at 24 °C on a fixed (8 h:16 h) light:dark photoperiod. At 4 h intervals throughout the 24 h period, bats were lavaged and the surfactant analysed for absolute and relative amounts of total phospholipid (PL), disaturated phospholipid (DSP) and cholesterol (Chol). N. geoffroyi experienced two peaks...

.... Coincident with the stimulus-dependent rearrangement of membrane phospholipids is a rapid redistribution of cholesterol from the outer to the inner membrane monolayer. This redistribution of cholesterol was observed when the stimulus was collagen or ADP. The data presented here show that epinephrine...

...Kathleen Boesze-Battaglia; Richard J. Schimmel ABSTRACT Photoreceptor rod cells and blood platelets are remarkably different, yet both illustrate a similar phenomenon. Both are strongly affected by membrane cholesterol, and the distribution of cholesterol in the membranes of both cell types...

...Elizabeth L. Crockett; Jeffrey R. Hazel ABSTRACT The role of cholesterol in the thermal adaptation of biological membranes is explored. Physical and chemical responses of membranes to acclimation temperature were evaluated using plasma membrane domains (basolateral and brush border) prepared from...