Homeostatic process

AletabolicFunctions. The chlorides are essential in the homeostatic processes maintaining fluid volume, osmotic pressure, and acid—base equihbria (11). Most chloride is present in body fluids a Htde is in bone salts. Chloride is the principal anion accompanying Na" in the extracellular fluid. Less than 15 wt % of the CF is associated with K" in the intracellular fluid. Chloride passively and freely diffuses between intra- and extracellular fluids through the cell membrane. If chloride diffuses freely, but most CF remains in the extracellular fluid, it follows that there is some restriction on the diffusion of phosphate. As of this writing (ca 1994), the nature of this restriction has not been conclusively estabUshed. There may be a transport device (60), or cell membranes may not be very permeable to phosphate ions minimising the loss of HPO from intracellular fluid (61). 

Opiates are useful analgesics because they reduce pain sensation without blocking feeling or other sensations. However, they also affect mood, iaduce euphoria, reduce mental acuity, and iaduce physical dependence. They can be immunosuppressive and dismpt other homeostatic processes through... 

Sleep is thought to be under the control of two independent processes one homeostatic (process S) and the other circadian (process C), which together... 

Sinensky, M. (1974) Homeoviscous adaptation - a homeostatic process thatregulates the viscosity of membrane lipids in Escherichia coli. Proceedings of the National Academy of Sciences of the, 71 (2), 522-525. 

All molecular systems involved in Ca2+ homeostatic processes are regulated by Ca2+ itself, which operates numerous feedback loops. That is, increase in cytosolic Ca2+ concentration induces a Ca2+-dependent inactivation of voltage-operated plasmalemmal Ca2+ channels. Fluctuations in [Ca2+]L differentially regulate Ca2+ transport across the endomembrane elevation of [Ca2+]L increases the susceptibility of RyRs and InsP3Rs to activation, and inhibits the SERCAs when [Ca2+]L falls, the SERCA pumping is much activated, and the Ca2+ release channels are inhibited (Burdakov et al., 2005 Burdakov and Verkhratsky 2006). 

The body s chemical processes are the same for handling chemicals used as pesticides as they are for other xenobiotics. The body does not know the use category of a chemical entering its system. The study of chemical residues in the body and their effects on homeostatic processes offers some hope of a better biological, as well as chemical understanding, of the life process itself. 

Wyatt JK, Dijk DJ, Ronda JM, Jewett ME, Powell JW, Dinges DF, Czeisler CA. Interaction of circadian- and sleep/wake homeostatic-processes modulate psychomotor vigilance test (PVT) performance. Sleep Res 1997 26 759. 

Figure 2 Several models have been proposed to conceptualize the interaction of circadian and homeostatic processes in sleep regulation. In the two-process model, a sleep homeostatic process increases during waking and decreases during sleep ( Process S ) and interacts with input from the circadian system that is independent of sleep and waking ( Process C ) to gate the occurrence of sleep and wakefulness. (Adapted from Ref. 1.)...

The HPA axis, the mediator of cortisol, also plays a central role in the homeostatic processes in human. Subjects with abdominal obesity show several signs of a perturbed regulation of the HPA axis. This is known to occur after chronic, submissive stress. In contrast, perceived environmental stress depends on personality characteristics [111]. Rosmond et al. found that men with cluster A personality disorders showed centralized body fat distribution independent of dexamethasone suppression. In contrast, men with impulsive (cluster B) and anxious (cluster C) personality disorders often have abdominal obesity in combination with a blunted dexamethasone suppression test, indicating a HPA axis disturbance [111],... 

Sodium ions are controlled in a homeostatic process involving aldosterone which increases sodium ion absorption in the distal convoluted tubules. 

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