downregulation

DEFINITION:

A decrease in the number of receptors for a chemical or drug on cell surfaces in a given area, usually due to long-term exposure to the agent. (Dorland's Illustrated Medical Dictionary, 29th edition)

Downregulation of aquaporin 2: The number of aquaporin 2 water channels will be decreased, i.e., regulated to a lower number of channels expressed on the luminal membrane (D. Bichet).

Downregulation of AQP2 means that there are many conditions with acquired nephrogenic diabetes insipidus (vasopressin-resistent polyuria) which result in a reduction in the levels of AQP2 protein in the collecting duct cells. Since AQP2 is essential for reabsorption of water from the collecting duct lumen back to the circulation, the absence or reduced levels of AQP2 (downregulation) results in the development of polyuria. Thus the conditions associated with this downregulation of AQP2 share many common features with the inherited forms of NDI (with mutations in vasopressin V2 receptor) since this condition is also associated with a reduced/absence of regulation of AQP2. This regulation is important for keeping the levels of AQP2 protein up, but it is also extremely important in regulating the trafficking of AQP2 from the reservoir in small vesicles to the apical plasma membrane (its active site for water reabsorption—the site where the water channel faces the water to be reabsorbed). This is why the studies of the very common acquired forms of NDI are very important in connection with inherited NDI (the shared elements of regulation or rather dysregulation) (S. Nielsen).

renal

DEFINITION:

Pertaining to the kidney.

AQP2 expression

DEFINITION:

The process, or the regulation of the process, by which the effects of the aquaporin-2 gene are manifested.

J

DEFINITION:

Symbol for joule .

J

DEFINITION:

Symbol for joule .

renal

DEFINITION:

Pertaining to the kidney.

expression

DEFINITION:

1. The aspect or appearance of the face (or surface of a cell) as determined by the physical or emotional state.

2. The act of squeezing or evacuating by pressure; a term used in pharmacy, surgery, and obstetrics.

3. The detectable effect of a gene.

4. A representation of value, relation, or the like (e.g., ratio).

model

DEFINITION:

1. Something that represents or simulates something else; a replica.
2. A reasonable facsimile of the body or any of its parts; used for demonstration and teaching purposes.
3. Cast, definition 5.
4. To imitate another's behavior; See modeling .
5. A hypothesis or theory.

UUO

DEFINITION:

Abbreviation for unilateral ureteral obstruction.

natriuresis

DEFINITION:

The excretion of sodium in the urine.

UUO

DEFINITION:

Abbreviation for unilateral ureteral obstruction.

urine

DEFINITION:

The fluid excreted by the kidneys, passed through the ureters, stored in the bladder, and discharged through the urethra. Urine, in health, has an amber color, a slight acid reaction, a peculiar odor, and a bitter, saline taste.

UUO

DEFINITION:

Abbreviation for unilateral ureteral obstruction.

urinary osmolality

DEFINITION:

The concentration of osmotically active particles in solution (in this case, urine) expressed in terms of osmoles of solute per kilogram of solvent. The osmolality is directly proportional to the colligative properties of solutions: osmotic pressure, boiling point elevation, freezing point depression, and vapor pressure lowering.

natriuresis

DEFINITION:

The excretion of sodium in the urine.

immunoblotting

DEFINITION:

See immunoblots .

NHE3

DEFINITION:

Abbreviation for type 3 Na(+)/H(+) exchanger.

NaPi-2

DEFINITION:

Abbreviation for type 2 Na-P(i) cotransporter.

BSC-1

DEFINITION:

Abbreviation for type 1 bumetanide-sensitive Na-K-2Cl cotransporter.

TSC

DEFINITION:

Abbreviation for thiazide-sensitive Na-Cl cotransporter.

immunocytochemistry

DEFINITION:

The biochemistry of cellular immunology.

downregulation

DEFINITION:

A decrease in the number of receptors for a chemical or drug on cell surfaces in a given area, usually due to long-term exposure to the agent. (Dorland's Illustrated Medical Dictionary, 29th edition)

Downregulation of aquaporin 2: The number of aquaporin 2 water channels will be decreased, i.e., regulated to a lower number of channels expressed on the luminal membrane (D. Bichet).

Downregulation of AQP2 means that there are many conditions with acquired nephrogenic diabetes insipidus (vasopressin-resistent polyuria) which result in a reduction in the levels of AQP2 protein in the collecting duct cells. Since AQP2 is essential for reabsorption of water from the collecting duct lumen back to the circulation, the absence or reduced levels of AQP2 (downregulation) results in the development of polyuria. Thus the conditions associated with this downregulation of AQP2 share many common features with the inherited forms of NDI (with mutations in vasopressin V2 receptor) since this condition is also associated with a reduced/absence of regulation of AQP2. This regulation is important for keeping the levels of AQP2 protein up, but it is also extremely important in regulating the trafficking of AQP2 from the reservoir in small vesicles to the apical plasma membrane (its active site for water reabsorption—the site where the water channel faces the water to be reabsorbed). This is why the studies of the very common acquired forms of NDI are very important in connection with inherited NDI (the shared elements of regulation or rather dysregulation) (S. Nielsen).

NHE3

DEFINITION:

Abbreviation for type 3 Na(+)/H(+) exchanger.

BSC-1

DEFINITION:

Abbreviation for type 1 bumetanide-sensitive Na-K-2Cl cotransporter.

TSC

DEFINITION:

Abbreviation for thiazide-sensitive Na-Cl cotransporter.

inner medullary

DEFINITION:

Pertaining to or situated in the inner medulla.

cortical

DEFINITION:

Pertaining to or of the nature of a cortex or bark.

NaPi-2

DEFINITION:

Abbreviation for type 2 Na-P(i) cotransporter.

compensatory

DEFINITION:

Making good a defect or loss; restoring a lost balance.

urinary

DEFINITION:

Pertaining to the urine; containing or secreting urine.

X

DEFINITION:

Symbol for Kienbock unit and xanthine or xanthosine . See also exposure , definition 3.

downregulation

DEFINITION:

A decrease in the number of receptors for a chemical or drug on cell surfaces in a given area, usually due to long-term exposure to the agent. (Dorland's Illustrated Medical Dictionary, 29th edition)

Downregulation of aquaporin 2: The number of aquaporin 2 water channels will be decreased, i.e., regulated to a lower number of channels expressed on the luminal membrane (D. Bichet).

Downregulation of AQP2 means that there are many conditions with acquired nephrogenic diabetes insipidus (vasopressin-resistent polyuria) which result in a reduction in the levels of AQP2 protein in the collecting duct cells. Since AQP2 is essential for reabsorption of water from the collecting duct lumen back to the circulation, the absence or reduced levels of AQP2 (downregulation) results in the development of polyuria. Thus the conditions associated with this downregulation of AQP2 share many common features with the inherited forms of NDI (with mutations in vasopressin V2 receptor) since this condition is also associated with a reduced/absence of regulation of AQP2. This regulation is important for keeping the levels of AQP2 protein up, but it is also extremely important in regulating the trafficking of AQP2 from the reservoir in small vesicles to the apical plasma membrane (its active site for water reabsorption—the site where the water channel faces the water to be reabsorbed). This is why the studies of the very common acquired forms of NDI are very important in connection with inherited NDI (the shared elements of regulation or rather dysregulation) (S. Nielsen).

UUO

DEFINITION:

Abbreviation for unilateral ureteral obstruction.

natriuresis

DEFINITION:

The excretion of sodium in the urine.

NaPi-2

DEFINITION:

Abbreviation for type 2 Na-P(i) cotransporter.

contralateral

DEFINITION:

Situated on, pertaining to, or affecting the opposite side, as opposed to ipsilateral.

kidney

DEFINITION:

One of a pair of vertebrate organs situated in the body cavity near the spinal column that excrete waste products of metabolism, in man are bean-shaped organs about 4-1/2 inches long lying behind the peritoneum in a mass of fatty tissue, and consist chiefly of nephrons by which urine is secreted, collected, and discharged into a main cavity whence it is conveyed by the ureter to the bladder.

compensatory

DEFINITION:

Making good a defect or loss; restoring a lost balance.

kidney

DEFINITION:

One of a pair of vertebrate organs situated in the body cavity near the spinal column that excrete waste products of metabolism, in man are bean-shaped organs about 4-1/2 inches long lying behind the peritoneum in a mass of fatty tissue, and consist chiefly of nephrons by which urine is secreted, collected, and discharged into a main cavity whence it is conveyed by the ureter to the bladder.

UUO

DEFINITION:

Abbreviation for unilateral ureteral obstruction.

permission

DEFINITION:

Formal consent; authorization.