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.

epithelial cells

DEFINITION:

Cells that cover the surface of the body and line its cavities.

arginine vasopressin

DEFINITION:

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

AVP

DEFINITION:

Arginine vasopressin.

concentrations

DEFINITION:

1. Increases in strength by evaporation.

2. The ratios of the mass or volume of a solute to the mass or volume of the solution or solvent.

transiently

DEFINITION:

1. A: passing especially quickly into and out of existence: transitory. B: passing through or by a place with only a brief stay or sojourn.

2. Affecting something or producing results beyond itself.

intracellular

DEFINITION:

Situated or occurring within a cell or cells.

calcium

DEFINITION:

A silvery yellow metal, the basic element of lime. Symbol, Ca; atomic number, 20; atomic weight, 40.08. It is found in nearly all organized tissues, being the most abundant mineral in the body. In combination with phosphorus it forms calcium phosphate, the dense, hard material of the teeth and bones. It is an essential dietary element, a constant blood calcium level being essential for the maintenance of the normal heartbeat, and for the normal functioning of nerves and muscles. It also plays a role in multiple phases of blood coagulation and in many enzymatic processes.

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.

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.

hormone

DEFINITION:

A product of living cells that circulates in body fluids and produces a specific effect on the activity of cells remote from its point of origin; especially: one exerting a stimulatory effect on a cellular activity.

hypophysiotropic hormones - Hormones produced by the hypothalamus, usually releasing hormones (see below), which maintain the endocrine functions of cells of the adenohypophysis.

neurohormone - A hormone secreted by a specialized neuron into the bloodstream, the cerebrospinal fluid, or the intercellular spaces of the nervous system.

releasing hormones - Hormones elaborated in one structure that cause the release of hormones from another structure, such as those from the hypothalamus that act on the adenohypophysis. The term is applied to substances of established chemical identity, whereas substances of unknown chemical structure are called releasing factors .

IMCD

DEFINITION:

Inner medullary collecting duct.

quantitative

DEFINITION:

1. Denoting or expressing a quantity.
2. Relating to the proportionate quantities or to the amount of the constituents of a compound.

integration

DEFINITION:

1. Assimilation; anabolic action or activity.

2. The combining of different acts so that they cooperate toward a common end; coordination.

3. Constructive assimilation into the personality of knowledge and experience.

4. In bacterial genetics, assimilation of genetic material from one bacterium (donor) into the chromosome of another (recipient).

AVP

DEFINITION:

Arginine vasopressin.

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.

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.

V2-receptor

DEFINITION:

See under "receptor."

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.

arginine vasopressin

DEFINITION:

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

oxytocin

DEFINITION:

1. An octapeptide, one of the major hormones made in the magnocellular hypothalamic neurons and stored in the posterior lobe of the pituitary, the other being vasopressin. It has uterine-contracting and milk-ejecting actions. It contributes to the second stage of labor.
2. The same oxytocic principle obtained synthetically or from the posterior pituitary of domestic animals, prepared in accordance with USP standards; it is administered intramuscularly or by intravenous infusion to induce active labor, increase the force of contractions in labor, contract uterine muscle after delivery of the placenta, control postpartum hemorrhage, and stimulate milk ejection.

selective

DEFINITION:

Having a high degree of selectivity.

oxytocin

DEFINITION:

1. An octapeptide, one of the major hormones made in the magnocellular hypothalamic neurons and stored in the posterior lobe of the pituitary, the other being vasopressin. It has uterine-contracting and milk-ejecting actions. It contributes to the second stage of labor.
2. The same oxytocic principle obtained synthetically or from the posterior pituitary of domestic animals, prepared in accordance with USP standards; it is administered intramuscularly or by intravenous infusion to induce active labor, increase the force of contractions in labor, contract uterine muscle after delivery of the placenta, control postpartum hemorrhage, and stimulate milk ejection.

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.

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.

selective

DEFINITION:

Having a high degree of selectivity.

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.

challenge

DEFINITION:

1. To administer a chemical substance to a patient for observation of whether the normal physiological response occurs.

2. In immunology, to administer antigen to evoke an immunologic response in a previously sensitized individual.

3. The administration of such a chemical or antigen in order to asses for a reponse. Called also "challenge test," "provocative test," and "provocation."

4. To order to halt and prove identify.

5. To take exception to; dispute.

6. To issue an invitation to compete against one, especially in single combat; dare, defy.

7. A stimulating or interesting task or problem.

8. A summons to a duel.

9. An invitation to compete in a sport.

10. A calling into question.

11. An exception taken to a juror.

12. A sentry's command to halt and prove identify.

AVP

DEFINITION:

Arginine vasopressin.

agent

DEFINITION:

Any power, principle, or substance capable of producing an effect, whether physical, chemical, or biological.

homologous

DEFINITION:

1. Corresponding in structure, position, origin, etc., as (a) the feathers of a bird and the scales of a fish, (b) antigen and its specific antibody, (c) allelic chromosomes.

2. Allogeneic.

3. Pertaining to an antibody and the antigen that elicited its production.

receptors

DEFINITION:

See definitions under "receptor."

trigger

DEFINITION:

1. To initiate, actuate, or set off.

2. To fire by pulling a trigger.

3. A movable lever that activates a device when it is squeezed; especially, the part of a firearm lock moved by the finger to fire a gun.

neurohypophysial hormones

DEFINITION:

Posterior pituitary hormones.

antagonists

DEFINITION:

1. Muscles whose actions are the direct opposite of that of other muscles.

oxytocin

DEFINITION:

1. An octapeptide, one of the major hormones made in the magnocellular hypothalamic neurons and stored in the posterior lobe of the pituitary, the other being vasopressin. It has uterine-contracting and milk-ejecting actions. It contributes to the second stage of labor.
2. The same oxytocic principle obtained synthetically or from the posterior pituitary of domestic animals, prepared in accordance with USP standards; it is administered intramuscularly or by intravenous infusion to induce active labor, increase the force of contractions in labor, contract uterine muscle after delivery of the placenta, control postpartum hemorrhage, and stimulate milk ejection.

V2

DEFINITION:

Vasopressin-2. See vasopressin-2 gene and vasopressin-2 receptor.

receptors

DEFINITION:

See definitions under "receptor."

AVP

DEFINITION:

Arginine vasopressin.

inhibition

DEFINITION:

Arrest or restraint of a process.

vasopressin receptor

DEFINITION:

A molecular structure to which the hormone, vasopressin, binds. See also receptor .

coupled

DEFINITION:

See coupling.

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.

vasopressin receptor

DEFINITION:

A molecular structure to which the hormone, vasopressin, binds. See also receptor .

V2 receptor

DEFINITION:

See under receptor .

novel

DEFINITION:

Of a new kind, or different from anything seen or known before.

vasopressin receptor

DEFINITION:

A molecular structure to which the hormone, vasopressin, binds. See also receptor .