Kidney

Kidney



The kidneys are organs of excretion in vertebrates shaped like peanuts. As part of the urinary system, kidney function filter wastes (especially urea) from the blood and threw it together with water in the form of urine. Branch of medicine that studies the kidneys and the disease is called nephrology.
Table of contents
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A basic anatomy
1.1 Location
1.2 Structural details
1.3 Organization
1.4 Functions of kidney homeostasis
2 Diseases and disorders
2.1 Default
2.2 Acquired
3 Dialysis and kidney transplants
3.1 Statistics kidney transplant
4 References
5 See also
6 External links

[Edit] Anatomical basis
[Edit] Location

Human beings have a pair of kidneys are located behind the stomach or abdomen. The kidneys are located on the right and left spine, below the liver and spleen. At the top (superior), the kidney is an adrenal gland (also called the suprarenal gland).

The kidneys are retroperitoneal, which means that lie behind the peritoneum lining the abdominal cavity. Both kidneys are located in the vicinity of vertebrae T12 to L3. Right kidney usually lies slightly below the left kidney to make room for the heart.

Some of the top of the kidneys are protected by the eleventh and twelfth ribs. Both kidneys wrapped by two layers of fat (perirenal and pararenal fat) which help reduce shock.
Pieces of kidney longitudinal
[Edit] Structural details

In adults, each kidney has a length of about 11 cm and 5 cm thick, weighing about 150 grams. Kidneys have a shape like a bean with the indentation facing the inside. In each kidney is an opening called the hilum of the renal artery that connects, renal vein, and ureter.
[Edit] Organization

Outermost part of the kidney called the cortex, the deeper part is called the medulla. Innermost part is called the pelvis. In the medulla of human kidney can also be seen the pyramids, which is opening channels gatherer. Kidney wrapped by a layer of loose connective tissue called the capsule. The basic functional unit of the kidney is the nephron that could be more than one million in each normal adult human kidney. Nephron function as regulator of water and solutes (especially electrolytes) in the body by filtering the blood, then mereabsorpsi fluid and molecules that are still needed for the body. Molecular and other liquid remaining will be discarded. Reabsorption and disposal are conducted using the countercurrent exchange mechanism and kotranspor. The final result is then excreted called urine. A nephron consists of a filter component called korpuskula (or Malpighian body), followed by the channels (tubules). Each roll contains korpuskula blood capillaries called the glomerulus within Bowman's capsule. Each glomerulus receive blood flow from afferent arteries. Of glomerular capillary walls have pores for filtration or filtration. Blood can be filtered through the porous walls thin epithelium of the glomerulus and Bowman's capsule due to the pressure of the blood which promote blood plasma. The resulting filtrate will go to Dalan kidney tubules. Blood that has been filtered to leave the kidney through efferent arteries. Among the blood in the glomerulus and the room filled with fluid in Bowman's capsule, there are three layers:

capillary endothelium cell layer of the glomerulus
rich layer of basement membrane proteins as
layer of epithelial cells lining Bowman's capsule (podosit)

With the help of pressure, fluid blood Dalan pushed out of the glomerulus, through the third layer and into the room in Bowman's capsule in the form of glomerular filtrate. Filtrate of blood plasma contains no blood cells or large protein molecules. Protein in the form of a small molecule can be found in this filtrate. Human blood through the kidneys 350 times a day with a rate of 1.2 liters per minute, resulting in glomerular filtrate 125 cc per minute. Glomerular filtration rate is used for diagnostic tests of renal function.
Kidney tissue. The blue color indicates a single tubule

Renal tubules is a continuation of the Bowman's capsule. The segment that drains glomerular filtrate from Bowman's capsule is called the proximal convoluted tubule. The next section is the loop which empties into the distal convoluted tubule. Loop of Henle was named by the inventor of Friedrich Gustav Jakob Henle at the beginning of the 1860s. Loop of Henle to maintain osmotic gradients in the countercurrent exchange used for filtration. Cells lining the tubules have many mitochondria that produce ATP and allow for active transport to reabsorb glucose, amino acids, and various mineral ions. Most of the water (97.7%) in the filtrate into the convoluted tubules and collecting tubules by osmosis. Fluid flows from the distal convoluted tubule into the collecting system consisting of:

connecting tubule
cortical collecting tubule
tubules kloektivus medularis

Place the loop of Henle intersect with afferent artery called the juxtaglomerular apparatus, containing the macula densa and juxtaglomerular cells. Tues juxtaglomerular is the site of synthesis and secretion of renin into the more viscous fluid along the tubules and channels to form urine, which is then brought into the bladder through the ureter.
[Edit] The function of kidney homeostasis

The kidneys regulate the pH, mineral ion concentration, and composition of water in the blood.

The kidneys maintain blood plasma pH in the range of 7.4 through the exchange of hydronium and hydroxyl ions. As a result, urine can be produced acid at pH 5 or alkaline at pH 8.

Sodium ion concentration is controlled by a homeostatic process involving aldosterone to increase the absorption of sodium ions in the convoluted tubule.

Increase or decrease in blood osmotic pressure due to excess or shortage of water will soon be detected by the hypothalamus signals the pituitary gland by negative feedback. The pituitary gland to secrete antidiuretic hormone (vasopressin, to suppress the secretion of water) that resulted in changes in the level of water absorption in the kidney tubules. As a result the concentration of tissue fluid will return to 98%.
[Edit] Diseases and disorders
[Edit] Default

Renal tubular acidosis
Congenital hydronephrosis
Congenital obstruction of urinary tract
Duplicated ureter
Horseshoe kidney
Polycystic kidney disease
Renal dysplasia
Unilateral small kidney

[Edit] Acquired

Diabetic nephropathy
Glomerulonephritis
Hydronephrosis is the enlargement of one or both kidneys caused by obstruction of urine flow.
Interstitial nephritis
Kidney stones are a common abnormality and usually painful.
Kidney Tumor
Wilms tumor
Renal cell carcinoma
Lupus nephritis
Minimal change disease
In nephrotic syndrome, the glomerulus has been damaged so much protein in the blood into the urine. Other frequent features of the nephrotic syndrome include swelling, low serum albumin, and high cholesterol.
Pyelonephritis is a kidney infection and is often caused by complications of urinary tract infection.
Renal failure
Acute renal failure
Chronic renal failure

[Edit] Dialysis and kidney transplants

Generally, a person can live a normal life with only one kidney. If both kidneys are not functioning normally, then someone needs to get a Renal Replacement Therapy (TPG). TPG can be done either temporarily or continuously. TPG consists of three, namely: Hemodialysis (Wash Blood), Peritoneal Dialysis (Wash cavity Stomach) and Renal Transplant (transplant). The basic principle of hemodialysis is to clean the blood by using the Artificial Kidney. While peritoneal dialysis using a membrane of the abdominal cavity (peritoneum) as a filter between the blood and fluid Dianial.

Kidney transplants are now quite common. The first successful transplant was announced on March 4, 1954 at Peter Bent Brigham Hospital in Boston, Massachusetts. The operation was conducted by Dr. Joseph E. Murray, who in 1990 received the Nobel Prize in physiology or medicine.

Kidney transplant can be done "cadaveric" (from someone who has died) or from a living donor (usually a family member). There are several advantages for transplantation from a living donor, including a better match, the donor can be thoroughly tested before transplant and the kidney is likely to have a longer lifespan. [1].
[Edit] Statistics kidney transplant
State kadaverik Transplantation Transplantation Transplantation of living donor total
Canada 724 388 1.112 (2000) [2]
France 1.991 2.127 136 (2003) [3]
Italy 1.489 1.624 135 (2003)
Spain 1.991 60 2.051 (year 2003)
United Kingdom 1.297 1.736 439 (2003) [4]
United States 8.670 6.468 15.138 (2003) [5]