nucleotide

DEFINITION:

Any of several compounds that consist of a ribose or deoxyribose sugar joined to a purine or pyrimidine base and to a phosphate group and that are the basic structural units of RNA and DNA.

receptors

DEFINITION:

See definitions under "receptor."

linked

DEFINITION:

In genetics, pertaining to linkage (def. 2); See also X-linked under gene .

mobilization

DEFINITION:

The process of making a fixed part or stored substance mobile, as by separating a part from surrounding structures to make it accessible for an operative procedure or by causing release into the circulation for body use of a substance stored in the body.

intracellular

DEFINITION:

Situated or occurring within a cell or cells.

cell

DEFINITION:

1. Any one of the minute protoplasmic masses that make up organized tissue, consisting of a nucleus which is surrounded by cytoplasm which contains the various organelles and is enclosed in the cell or plasma membrane. A cell is the fundamental, structural, and functional unit of living organisms.

2. A small, more or less closed space.

neuroglial cells - The cells of the supportive tissue of the central nervous system (neuroglia); these non-neural cells are of three kinds: astrocytes, oligodendrocytes (collectively termed macroglia) and microglia.

reticular cells - The cells forming the reticular fibers of connective tissue; those forming the framework of lymph nodes, bone marrow, and spleen are part of the reticuloendothelial system and under appropriate stimulation may differentiate into macrophages.

stem cell - 1. Any precursor cell.

2. A blood cell progenitor, or mother cell, having the capacity for both replication and differentiation, and giving rise to various morphologically recognizable precursors of different blood cell lines, such as the proerythrocyte and myeloblast, which cannot self-replicate and must differentiate into more mature daughter cells.

renal collecting duct

DEFINITION:

Also known as the tubulus renalis colligens, or renal collecting tubule: That structure of the kidney consisting of the arcuate renal tubule, straight collecting tubule, and papillary duct considered together.

cells

DEFINITION:

See definitions for "cell."

ATP

DEFINITION:

Adenosine triphosphate.

arginine vasopressin

DEFINITION:

Vasopressin containing arginine, as that from most mammals, including man.

AVP

DEFINITION:

Arginine vasopressin.

osmotic water permeability

DEFINITION:

The ability to channel water across a membrane in response to a concentration gradient.

in vitro

DEFINITION:

Within a glass; observable in a test tube; in an artificial environment.

inner medullary

DEFINITION:

Pertaining to or situated in the inner medulla.

collecting ducts

DEFINITION:

Renal collecting tubules: the arcuate renal tubule, straight collecting tubule, and papillary duct considered together.

IMCD

DEFINITION:

Inner medullary collecting duct.

ATP

DEFINITION:

Adenosine triphosphate.

AVP

DEFINITION:

Arginine vasopressin.

ATP

DEFINITION:

Adenosine triphosphate.

adenosine

DEFINITION:

A purine nucleoside, adenine linked by its N9 nitrogen to the C1 carbon of ribose. It is a component of ribonucleic acid and its nucleotides play major roles in the reactions and regulation of metabolism. Symbol A.

adenosine monophosphate - A nucleotide involved in energy metabolism.

adenosine triphosphate - A nucleotide involved in energy metabolism and required for RNA synthesis; it occurs in all cells and is used to store energy in the form of high-energy phosphate bonds.

cAMP

DEFINITION:

Cyclic AMP (cyclic adenosine monophosphate).

analogue

DEFINITION:

1. A part or organ having the same function as another, but of a different evolutionary origin.

2. A chemical compound with a structure similar to that of another but differing from it in respect to a certain component; it may have a similar or opposite action metabolically.

cAMP

DEFINITION:

Cyclic AMP (cyclic adenosine monophosphate).

forskolin

DEFINITION:

Activator of adenylate cyclase leading to an increase in the intracellular concentration of cAMP.

(Sources: A. Laurenza, et al., Trends Pharm. Sci. 10: 442-447 (1989) and R. Barber and T.J. Goka, J. Cyclic Nucleotide Protein Phos. Res. 10:23-29 (1985) @www.lclabs.com/PROFILE/D-F/F-9929.php4.)

ATP

DEFINITION:

Adenosine triphosphate.

AVP

DEFINITION:

Arginine vasopressin.

cAMP

DEFINITION:

Cyclic AMP (cyclic adenosine monophosphate).

ATP

DEFINITION:

Adenosine triphosphate.

AVP

DEFINITION:

Arginine vasopressin.

inhibitor

DEFINITION:

1. Any substance that interferes with a chemical reaction, growth, or other biological activity.

2. A chemical substance that inhibits an enzyme reaction.

protein kinase C

DEFINITION:

Any of a family of protein kinase isozymes, occurring in numerous tissues, that catalyze the phosphorylation of specific serine or threonine residues of a variety of intracellular proteins, altering their activities. The enzymes are activated via receptor binding by the hormones, growth factors, and other agents that cause increases in intracellular calcium and cleavage of phosphoinositides; some isozymes require calcium and phospholipid for activity, which is enhanced by diacylglycerol. The enzyme is involved in several types of cellular signal transduction and has been shown to play a role in platelet activation and in the inhibition of some peptide hormone receptors and to be a binding site for phorbol esters and other tumor promoters, as well as having numerous other roles and substrates, only some of which are known.

agonist

DEFINITION:

1. In anatomy, a prime mover.

2. In pharmacology, a drug that has affinity for and stimulateS physiologic activity at cell receptors normally stimulated by naturally occurring substances.

putative

DEFINITION:

1. Commonly accepted or supposed.

2. Assumed to exist or to have existed.

nucleotide

DEFINITION:

Any of several compounds that consist of a ribose or deoxyribose sugar joined to a purine or pyrimidine base and to a phosphate group and that are the basic structural units of RNA and DNA.

receptor

DEFINITION:

1. A molecular structure within a cell or on the surface characterized by (1) selective binding of a specific substance and (2) a specific physiologic effect that accompanies the binding, e.g., membrane receptors for peptide hormones, neurotransmitters, antigens, complement fragments, and immunoglobulins and nuclear receptors for steroid hormones.

2. A sensory nerve terminal that responds to stimuli of various kinds; classified in various ways including by the type of stimulus and by the location in the body.

V2 receptor - The structure to which the antidiuretic hormone, arginine vasopressin binds.

inhibition

DEFINITION:

Arrest or restraint of a process.

AVP

DEFINITION:

Arginine vasopressin.

cellular

DEFINITION:

Pertaining to, or made up of, cells.

cAMP

DEFINITION:

Cyclic AMP (cyclic adenosine monophosphate).

activation

DEFINITION:

1. The act or process of rendering active.

2. The transformation of a proenzyme into an active enzyme by the action of a kinase or another proenzyme.

3. Gain in the purifying of sewage by means of activated sludge.

4. The process by which the central nervous system is stimulated into activity through the mediation of the reticular activating system.

5. The deliberate induction of a pattern of electrical activity in the brain in electroencephalography.

signaling

DEFINITION:

A molecule or chemical which cues a responsive behavior in its surrounding environment.

pathway

DEFINITION:

1. A path or course, especially a course followed in the attainment of a specific end.
2. The nerve structures through which an impulse passes between groups of nerve cells or between the central nervous system and an organ or muscle.
3. Metabolic pathway.