/ chapter 7 in Visual C#.NET

Decoder QR Code in Visual C#.NET / chapter 7

132 / chapter 7
Decode Denso QR Bar Code In C#.NET
Using Barcode reader for .NET framework Control to read, scan QR image in Visual Studio .NET applications.
www.OnBarcode.com
Read QR In Visual C#.NET
Using Barcode scanner for VS .NET Control to read, scan read, scan image in Visual Studio .NET applications.
www.OnBarcode.com
Plasma volume
Decode Bar Code In Visual C#.NET
Using Barcode reader for .NET framework Control to read, scan bar code image in .NET applications.
www.OnBarcode.com
Barcode Reader In C#.NET
Using Barcode recognizer for .NET framework Control to read, scan read, scan image in VS .NET applications.
www.OnBarcode.com
Excess ingestion
QR Code Scanner In C#.NET
Using Barcode decoder for Visual Studio .NET Control to read, scan Denso QR Bar Code image in .NET applications.
www.OnBarcode.com
QR-Code Reader In Visual Studio .NET
Using Barcode recognizer for ASP.NET Control to read, scan QR Code image in ASP.NET applications.
www.OnBarcode.com
Blood pressure
QR Code Decoder In .NET Framework
Using Barcode recognizer for .NET framework Control to read, scan Quick Response Code image in .NET applications.
www.OnBarcode.com
Reading Quick Response Code In VB.NET
Using Barcode decoder for VS .NET Control to read, scan QR Code 2d barcode image in .NET applications.
www.OnBarcode.com
Fluid osmolality
Bar Code Recognizer In C#
Using Barcode scanner for Visual Studio .NET Control to read, scan bar code image in .NET framework applications.
www.OnBarcode.com
Bar Code Recognizer In C#
Using Barcode recognizer for VS .NET Control to read, scan bar code image in VS .NET applications.
www.OnBarcode.com
Baroreceptors
UPC-A Supplement 2 Scanner In C#.NET
Using Barcode recognizer for .NET framework Control to read, scan UPCA image in .NET applications.
www.OnBarcode.com
Decode Matrix 2D Barcode In Visual C#
Using Barcode recognizer for VS .NET Control to read, scan Matrix 2D Barcode image in VS .NET applications.
www.OnBarcode.com
Osmoreceptors
Decoding ISBN - 10 In C#
Using Barcode reader for Visual Studio .NET Control to read, scan International Standard Book Number image in .NET applications.
www.OnBarcode.com
PDF417 Scanner In VB.NET
Using Barcode decoder for Visual Studio .NET Control to read, scan PDF417 image in .NET framework applications.
www.OnBarcode.com
ADH secretion
Recognizing EAN128 In None
Using Barcode reader for Font Control to read, scan UCC - 12 image in Font applications.
www.OnBarcode.com
Decoding 1D Barcode In Java
Using Barcode reader for Java Control to read, scan Linear image in Java applications.
www.OnBarcode.com
ADH secretion
Recognize Barcode In VS .NET
Using Barcode reader for .NET framework Control to read, scan read, scan image in Visual Studio .NET applications.
www.OnBarcode.com
ECC200 Reader In None
Using Barcode recognizer for Font Control to read, scan Data Matrix ECC200 image in Font applications.
www.OnBarcode.com
Water reabsorption
Data Matrix 2d Barcode Recognizer In Visual C#
Using Barcode decoder for .NET Control to read, scan read, scan image in Visual Studio .NET applications.
www.OnBarcode.com
Bar Code Decoder In .NET
Using Barcode recognizer for VS .NET Control to read, scan read, scan image in .NET applications.
www.OnBarcode.com
Water reabsorption
Total body water
Total body water
Figure 7 16 Regulation of water balance The 2 major pathways for altering total body
water On the left, changes in antidiuretic hormone (ADH) release from the anterior pituitary are triggered by changes in blood volume On the right, decreased osmolality causes swelling of osmoreceptor cells in the anterior hypothalamus, which inhibits their firing and inhibits adjacent superoptic nuclei cells that reduces ADH secretion from their axonal extensions in the posterior pituitary
Renal arterioles and mesangial cells also participate in this constrictor response, and so a high plasma concentration of ADH, quite apart from its effect on tubular water permeability, may promote the retention of both sodium and water by lowering GFR
Osmoreceptor Control of ADH Secretion
We have seen how changes in ECF volume simultaneously elicit reflex changes in the excretion of both sodium and water This is adaptive because the situations causing ECF volume alterations are often associated with loss or gain of both sodium and water in approximately proportional amounts In contrast, we see now that changes in total-body water in which no change in total-body sodium occurs are compensated by alterations in water excretion but not in sodium excretion The major effect of gaining or losing water without corresponding changes in sodium is a change in the osmolality of the body fluids This is a key point because, under conditions of gain or loss of water without solute, the receptors that initiate the reflexes controlling ADH secretion are osmoreceptors: receptors responsive to
control of sodium and water excretion / 133
changes in osmolality Most osmoreceptors are located in tissues surrounding the 3rd cerebral ventricle These tissues contain fenestrated capillaries, which allow rapid adjustment of interstitial composition when plasma composition changes The hypothalamic cells that secrete ADH receive neural input from the osmoreceptors8 Via these connections, an increase in osmolality stimulates them and increases their rate of ADH secretion Conversely, decreased osmolality inhibits ADH secretion (see Figure 7 16) For example, when a person drinks 1 L of water, the excess water lowers the body fluid osmolality, which reflexively inhibits ADH secretion via the hypothalamic osmoreceptors As a result, water permeability of the collecting ducts becomes very low, little or no water is reabsorbed from these segments, and a large volume of extremely dilute (hypo-osmotic) urine is excreted In this manner, the excess water is eliminated Conversely, when a pure-water deficit occurs (eg, because of water deprivation), the osmolality of the body fluids is increased, ADH secretion is reflexively stimulated, water permeability of the collecting ducts is increased, water reabsorption is maximal, and a very small volume of highly concentrated (hyperosmotic) urine is excreted By this means, relatively less of the filtered water than solute is excreted, which lowers body fluid osmolality toward normal We have described 2 different major afferent pathways controlling the ADHsecreting hypothalamic cells: one from baroreceptors and one from osmoreceptors These hypothalamic cells are, therefore, true integrators, whose rate of activity is determined by the total synaptic input to them Thus, a simultaneous increase in plasma volume and decrease in body fluid osmolality cause strong inhibition of ADH secretion Conversely, a simultaneous decrease in plasma volume and increase in osmolality produce very marked stimulation of ADH secretion However, what happens when baroreceptor and osmoreceptor inputs oppose each other (eg, if plasma volume and osmolality are both decreased) In general, because of the high sensitivity of the osmoreceptors, the osmoreceptor influence predominates over that of the baroreceptor when changes in osmolality and plasma volume are small to moderate However, a very large change in plasma volume will take precedence over decreased body fluid osmolality in influencing ADH secretion; under such conditions, water is retained in excess of solute, and the body fluids become hypo-osmotic (for the same reason, plasma sodium concentration decreases) In essence, it is more important for the body to preserve vascular volume and thus ensure an adequate CO than it is to preserve normal osmolality The ADH-secreting cells also receive synaptic input from many other brain areas Thus, ADH secretion and, hence, urine flow can be altered by pain, fear, and a variety of other factors, including drugs such as alcohol, which inhibits ADH release However, this complexity should not obscure the generalization that ADH secretion is determined over the long term primarily by the states of body fluid osmolality and plasma volume
8 Recent evidence suggests that there are both osmolality-sensing and direct sodium concentration-sensing cells in the brain, the latter via a special class of sodium channels located primarily in glial cells In addition, the ADH-secreting cells in the hypothalamus may also respond to osmolality in the cerebrospinal fluid, which responds on a slower time scale to changes in plasma composition
Copyright © OnBarcode.com . All rights reserved.