glomerulus


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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

(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.

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.

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]
References in periodicals archive ?
Second, pathologists expressed that the process of calculating the percentage of the glomerulus involved by a specific descriptor across multiple biopsy levels was time consuming and inefficient.
The mesangium domain in the glomerulus of the kidney consists of mesangium cells and mesangium substrates, including type IV collagen.
All 9 cases with Diffuse Endocapillary Proliferative change in the glomerulus turned out to be DEPGN.
Kriz, "Podocytes in glomerulus of rat kidney express a characteristic 44 KD protein," Journal of Histochemistry and Cytochemistry, vol.
(b) An example of the increase in glomerular volume in an untreated control glomerulus (solid line) and in a glomerulus after treatment with an injurious agent such as protamine (dotted line) as described previously [7, 8].
Significant difference was observed in the value of mean diameter of glomerulus (p-value = 0.001*) when compared between groups A, B, C and D.
[89] described the fuses kidney rat of age of 7 days consisting of cortex and the medulla, the cortex contain renal corpuscles and renal tubules, cortical rays contain arteries feeding kidney with little connective tissue, each renal corpuscle contain glomerulus and Bowmans Capsule, renal tubules which consist of proximal convoluted tubules contain columnar cells with basal nucleus and of distal convoluted tubules contain cubic cells with circular nucleus.
The alleviation of podocyte damage was related to alteration in the synthesis of caspase-3, transforming growth factor-beta 1, and Wilms' tumour-1 protein in the glomerulus.
This is defined by glomerular involvement in less than 50% of the glomeruli, whether it is segmental (part of the glomerulus) or global (the whole glomerulus).
Thickening of the glomerulus vessel wall was observed only at the maximum honey dose.
Since it has been reported that receptors for incretins were not expressed within glomerulus [7], protective effects of DPP4i for kidney might depend on another substrate for DPP4.
This region, the VAlv glomerulus, does a lot of growing when flies are young, the researchers found.