nephron


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nephron

 [nef´ron]
the structural and functional unit of the kidney, each nephron being capable of forming urine by itself. The nephron consists of the renal corpuscle, the proximal convoluted tubule, the descending and ascending limbs of the loop of Henle, the distal convoluted tubule, and the collecting tubule. Each kidney is an aggregation of about a million nephrons. The specific function of the nephron is to remove from the blood plasma certain end products of metabolism, such as urea, uric acid, and creatinine, and also any excess sodium, chloride, and potassium ions. By allowing for reabsorption of water and some electrolytes back into the blood, the nephron also plays a vital role in the maintenance of normal fluid balance in the body.

The nephron is a complex system of arterioles, capillaries, and tubules. Blood is brought to the nephron via the afferent arteriole. As the blood flows through the glomerulus (a network of capillaries), about one-fifth of the plasma is filtered through the glomerular membrane and collects in the malpighian (Bowman's) capsule, which encases the glomerulus. The fluid then passes through the proximal tubule, from there into the loop of Henle, then into the distal tubule, and finally into the collecting tubule. As the fluid is making its tortuous journey through these various tubules, most of its water and some of the solutes are reabsorbed into the blood via the peritubular capillaries. The water and solutes remaining in the tubules become urine.

neph·ron

(nef'ron),
A long, convoluted, tubular structure in the kidney, consisting of the renal corpuscle, the proximal tubule, the nephronic loop, and the distal tubule.
See also: uriniferous tubule.
[G. nephros, kidney]

nephron

/neph·ron/ (nef´ron) the structural and functional unit of the kidney, numbering about a million in the renal parenchyma, each being capable of forming urine; see also renal tubules, under tubule.

nephron

(nĕf′rŏn)
n.
The functional excretory unit of the vertebrate kidney that regulates the amount of water in the body and filters wastes from the blood to produce urine.

nephron

[nef′ron]
Etymology: Gk, nephros, kidney
a structural and functional unit of the kidney resembling a microscopic funnel with a long stem and two convoluted tubular sections. Each kidney contains about 1.25 million nephrons. All nephrons have a renal corpuscle and renal tubules. Juxtamedullary nephrons also have loops of Henle. Each renal corpuscle consists of a glomerulus of renal capillaries enclosed within Bowman's capsule. The renal corpuscles and the convoluted parts of the renal tubules are located in the cortex of the kidney. The loops of Henle and collecting tubules are located in the medulla. Urine is formed in the renal corpuscles and renal tubules by filtration, reabsorption, and secretion. See also kidney, malpighian corpuscle.
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Nephron

nephron

The functional anatomic unit of the kidney, which consists of a glomerulus, convoluted tubules and a loop of Henle (nephron loop)

neph·ron

(nef'ron)
A long convoluted tubular structure in the kidney, consisting of the renal corpuscle, the proximal convoluted tubule, the nephronic loop, and the distal convoluted tubule.
[G. nephros, kidney]

nephron

the MALPIGHIAN BODY and the associated tubule of the vertebrate kidney a structure about 5 cm long in humans. In each human kidney there are about one million nephrons, making a total for both kidneys of around fifty miles of tubules. Inflammation of the tubules is called nephritis.

Nephron

The smallest functional unit of the kidney involved in the removal of waste products and excess water from the blood.

nephron

functional unit of kidney, i.e. Bowman's capsule, proximal convoluted tubule, loop of Henle and distal convoluted tubule
  • collecting tubule straight portion of nephron; lies within renal cortex

  • convoluted tubule portion of nephron immediately distal to Bowman's capsule, made up of descending and ascending limbs of loop of Henle, acting respectively as a selective absorbing membrane and a collecting duct for urine

nephron

the structural and functional unit of the kidney, each nephron being capable of forming urine by itself. The nephron consists of the renal corpuscle, the proximal convoluted tubule, the descending and ascending limbs of the loop of Henle, the distal convoluted tubule, and the collecting tubule. Each kidney is an aggregation of many nephrons. The specific function of the nephron is to remove from the blood plasma certain end-products of metabolism, such as urea, uric acid and creatinine, and to regulate excretion of sodium, chloride, potassium and other ions. By allowing for reabsorption of water and some electrolytes back into the blood, the nephron also plays a vital role in the maintenance of normal fluid balance in the body.
The nephron is a complex system of tubules. Blood is brought to the nephron via the afferent arteriole. As the blood flows through the glomerulus (a network of capillaries), about one-fifth of the plasma is filtered through the glomerular membrane and collects in the glomerular (Bowman's) capsule, which encases the glomerulus. The fluid then passes through the proximal tubule, from there into the loop of Henle, then into the distal tubule, and finally into the collecting tubule (collecting duct). As the fluid is making its tortuous journey through these various tubules, most of its water and some of the solutes are reabsorbed into the blood via the peritubular capillaries. The water and solutes remaining in the tubules become urine.

intact-nephron hypothesis
nephron loop
see renal tubule.
References in periodicals archive ?
Pathophysiology of drug-induced nephropathy Level of the nephron Action Drugs Preglomerular Afferent arteriolar Cyclosporine (afferent arteriole) constriction Glomerulus Decreased GFR NSAIDs (prostaglandins) Gold, NSAIDs Glomerulonephritis Penicillamine, cisplatin Proximal tubules Acute tubular necrosis Aminoglycosides, radiocontrast dyes Distal tubules Renal tubular ACE inhibitors, acidosis type 4 cyclosporine Tubules and ducts Crystalluria Acyclovir, sulphonamide Interstitium Interstitial nephritis Penicillin, allopurinol Renal papilla Papillary necrosis NSAIDs, analgesics Table 2.
In healthy humans, urinary exosome analysis has identified over 1000 proteins from different segments of the nephron, but, most importantly, 34 of them were implicated in many kidney diseases such as autosomal dominant polycystic kidney disease type 1 (polycystin-1), autosomal dominant and recessive nephrogenic diabetes (aquaporin-2), antenatal Bartter syndrome type 1 (Na-K-2Cl symport), and Gitelman's syndrome (thiazide-sensitive Na-Cl cotransporter) (45).
7) Permeability factor, a low molecular weight protein, is also believed to induce proteinuria and injury to the nephron.
GFR, SNGFR, glomerular capillary pressure (PGd, single nephron plasma flow (Qa), single nephron filtration fraction (SNFF), afferent (AR) and efferent (ER) resistances, afferent (7A) and efferent (7rE) oncotic pressure and ultrafiltration coefficient (Kf) were calculated.
Figure 2 (p22) shows the sequence of events occurring in the nephrons when the glomerulus suffers injury.
Morphology of the nephron in the mesonephros of Bufo bufo (Amphibia, Anura, Bufonidae).
Two splice variants of the Wilms' tumor 1 gene have distinct functions during sex determination and nephron formation.
The above findings indicate that both too low and too high maternal salt intakes retard development of new glomeruli, resulting in a nephron deficit.
Alveolus structure and gas exchange in the lungs, nephron structure and water retention in the kidneys, villus structure and nutrient absorption in the small intestine, and root-hair structure and nutrient absorption in plants are all biological examples in which surface area plays a key role in living things.
Atubular glomeruli and glomerular cysts--a possible pathway for nephron loss in the human kidney.
Finally, aldosterone stimulates the distal tubule of the nephron to "increase" sodium reabsorption to maintain blood volume.