glomerulus


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Related to glomerulus: Proximal convoluted tubule, Collecting duct

glomerulus

 [glo-mer´u-lus] (pl. glomer´uli) (L.)
1. a small tuft or cluster, such as a small convoluted mass of capillaries.
2. a network of vascular tufts encased in the malpighian capsule of the kidney. adj., adj glomer´ular.

The glomerulus is an integral part of the nephron, the basic unit of the kidney. Each nephron is capable of forming urine by itself, and each kidney has approximately a million nephrons. The specific function of each glomerulus is to bring blood (and the waste products it carries) to the nephron. As the blood flows through the glomerulus, about one fifth of the plasma passes through the glomerular membrane, collects in the malpighian capsule, and then flows through the renal tubules. Much of this fluid passes back into the blood via the small capillaries around the tubules (peritubular capillaries). The continuous filtration of fluid from the glomeruli and its reabsorption into the peritubular capillaries are made possible by a high pressure in the glomerular capillary bed and a low pressure in the peritubular bed.

Any disease of the glomeruli, such as acute or chronic glomerulonephritis, must be considered serious because it interferes with the basic functions of the kidneys, that is, filtration of liquids and excretion of certain end products of metabolism and excess sodium, potassium, and chloride ions that may accumulate in the blood.

glo·mer·u·lus

, pl.

glo·mer·u·li

(glō-mer'yū-lŭs, -ū-lī),
1. A plexus of capillaries.
2. A tuft formed of capillary loops at the beginning of each nephric tubule in the kidney; this tuft, with its capsule constitutes the corpusculum renis (renal corpuscle). Synonym(s): malpighian glomerulus, malpighian tuft
3. The twisted secretory portion of a sweat gland.
4. A cluster of dendritic ramifications and axon terminals forming a complex synaptic relationship and surrounded by a glial sheath.
Synonym(s): glomerule
[Mod. L. dim. of L. glomus, a ball of yarn]

glomerulus

/glo·mer·u·lus/ (glo-mer´u-lus) pl. glomer´uli   [L.] a small tuft or cluster, as of blood vessels or nerve fibers; often used alone to designate one of the renal glomeruli.
olfactory glomerulus  one of the small globular masses of dense neuropil in the olfactory bulb, containing the first synapse in the olfactory pathway.
renal glomerulus  globular tufts of capillaries, one projecting into the expanded end or capsule of each of the uriniferous tubules, which together with the glomerular capsule constitute the renal corpuscle.

glomerulus

(glō-mĕr′yə-ləs)
n. pl. glomeru·li (-lī′)
1. A small cluster or mass of blood vessels or nerve fibers.
2. A tuft of capillaries situated within a Bowman's capsule at the end of a renal tubule in the vertebrate kidney that filters waste products from the blood and thus initiates urine formation.

glomerulus

[glōmer′yoo͡ləs] pl. glomeruli
Etymology: L, small ball
1 a tuft or cluster.
2 a structure composed of blood vessels or nerve fibers, such as a renal glomerulus. glomerular, adj.

glo·mer·u·lus

, pl. glomeruli (glō-meryū-lŭs, -lī)
1. A plexus of capillaries.
2. A tuft formed of capillary loops at the beginning of each nephric tubule in the kidney; this tuft with its capsule constitutes the renal corpusculum (malpighian body).
3. The twisted secretory portion of a sweat gland.
4. A cluster of dendritic ramifications and axon terminals forming a complex synaptic relationship and surrounded by a glial sheath.
Synonym(s): Bowman capsule, glomerule.
[Mod. L. dim. of L. glomus, a ball of yarn]

glomerulus

(glō-mĕr′ū-lŭs) plural.glomeruli [L.]
Enlarge picture
FILTRATION IN GLOMERULUS
1. One of the capillary networks that are part of the renal corpuscles in the nephrons of the kidney. Each is surrounded by a Bowman's capsule, the site of renal (glomerular) filtration, which is the first step in the formation of urine. See: illustration
2. A group of twisted capillaries or nerve fibers.

olfactory glomerulus

A neural network found in the olfactory bulb, formed by the dendrites of mitral cells intertwined with the axons of olfactory receptor cells.

glomerulus

A microscopic, spherical tuft of blood capillaries, especially that within the BOWMAN'S CAPSULES of the kidney, through which urine is filtered. From the Latin glomus , a ball of thread.

glomerulus

a knot of capillaries found in the vertebrate kidney, enclosed in the BOWMAN'S CAPSULE. Substances such as water and any small molecules dissolved in it filter from the blood, across the endothelium of the capillaries and the epithelium of the capsule, into the tubules leading to the LOOP OF HENLE.

Glomerulus (glomeruli)

A small tuft of blood capillaries in the kidney, responsible for filtering out waste products.

glomerulus

tuft of capillary loops within the (Bowman's) capsule of a renal nephron

glo·mer·u·lus

, pl. glomeruli (glō-meryū-lŭs, -lī)
1. A plexus of capillaries.
2. A tuft formed of capillary loops at the beginning of each nephric tubule in the kidney.
3. The twisted secretory portion of a sweat gland.
Synonym(s): Bowman capsule.
[Mod. L. dim. of L. glomus, a ball of yarn]

glomerulus (glōmer´yələs),

n a cluster of blood vessels or nerve fibers, such as the cluster of blood vessels in the kidney that function as filters of the plasma portion of the blood.

glomerulus

pl. glomeruli [L.] a small tuft or cluster.

cerebellar glomerulus
termination sites for dendrites and axons of cerebellar and medullary and spinal nerve fibers.
olfactory glomerulus
termination points of olfactory nerves in the olfactory lobes.
renal glomerulus
a small convoluted mass of capillaries, a network of vascular tufts, encased in the malpighian or Bowman's capsule.
The glomerulus is an integral part of the nephron, the basic unit of the kidney. Each nephron is capable of forming urine by itself, and each kidney has many nephrons. The specific function of each glomerulus is to bring blood (and the waste products it carries) to the nephron. As the blood flows through the glomerulus, about one-fifth of the plasma passes through the glomerular membrane, collects in the malpighian capsule, and then flows through the renal tubules. Much of this fluid passes back into the blood via the small capillaries around the tubules (peritubular capillaries). The continuous filtration of fluid from the glomeruli and its reabsorption into the peritubular capillaries is made possible by a high pressure in the glomerular capillary bed and a low pressure in the peritubular bed.
Any disease of the glomeruli, such as acute or chronic glomerulonephritis, must be considered serious because it interferes with the basic functions of the kidneys; that is, filtration of liquids and excretion of certain end products of metabolism and excess sodium, potassium and chloride ions that may accumulate in the blood.
References in periodicals archive ?
During the morphometry of renal cortex of the this experimental group (test 4) we detected the increasing of the size of renal corpuscle and renal glomerulus in 13.
About 99 per cent of substances filtered at the glomerulus are reabsorbed along the renal tubules.
The glomerulus, a portion of the nephron, is composed of a delicate capillary network.
These proteins are usually filtered by the glomerulus and reabsorbed by the tubules.
Diabetes alters the pressure and flow in the glomerulus and causes a number of complex biochemical changes in their operation.
Consistent with the renal functional findings, diabetic kidneys showed significantly increased glomerulus size, with mesangial matrix expansion, mesangial cell proliferation, and capillary wall thickness.
The nodular lesions are characterized by the accumulation of homogenous, eosinophilic material within the mesangium, which causes accentuated expansion of the mesangial regions of the glomerulus.
Creatinine is filtered at the glomerulus but does not get reabsorbed by the renal tubules, so the amount in the blood and urine is a measure of GFR.
It's better if it's produced by the proximal tubule, for example, where a good deal of the injury occurs, rather than filtered by the glomerulus and reabsorbed by the proximal tubule.
The process is typically initiated by a toxic injury to tubular epithelial cells in various nephron segments or by injury to specific cell types in the glomerulus.
Light microscopy examination showed five normal glomeruli without any evidence of glomerulosclerosis or hypertensive changes and one glomerulus that was obsolescent.
This leads to destructive changes in the kidney's blood vessels, accompanied by changes in the glomerulus (the part of the kidney responsible for filtering waste products out of the bloodstream).