molecular

DEFINITION:

Of, pertaining to, or composed of molecules.

water channels

DEFINITION:

Channels in a cell membrane that permit passage of water molecules; chemical substances such as vasopressin cause the opening of new channels and increase permeability.

aquaporins

DEFINITION:

A family of membrane channel proteins that serve as selective pores through which water crosses the plasma membranes of many human tissues and cell types.

CO

DEFINITION:

Cardiac output.

biophysical

DEFINITION:

Pertaining to biophysics.

biological membranes

DEFINITION:

The membranes of living organisms.

molecular

DEFINITION:

Of, pertaining to, or composed of molecules.

physiology

DEFINITION:

1. The science which treats of the functions of the living organism and its parts, and of the physical and chemical factors and processes involved.

2. The basic processes underlying the functioning of a species or class of organism, or any of its parts or processes.

water balance

DEFINITION:

Fluid balance.

pathophysiology

DEFINITION:

The physiology of abnormal states; specif.: the functional changes that accompany a particular syndrome or disease.

water balance disorders

DEFINITION:

Disorders caused by the disproportional relationship between the body's ingestion and excretion of water and electrolytes.

focus

DEFINITION:

1. The point of convergence of light rays or of the waves of sound.

2. The chief center of a morbid process.

vasopressin

DEFINITION:

1. One of two octapeptide hormones formed by the neuronal cells of the hypothalamic nuclei and stored in the posterior lobe of the pituitary gland (neurohypophysis), the other being oxytocin. It stimulates the contraction of the muscular tissue of the capillaries and arterioles, raising the blood pressure. It promotes contraction of the intestinal musculature and increases peristalsis, and also exerts some contractile influence on the uterus. It also has a specific effect on the epithelial cells of the distal portion of the uriniferous tubule, augmenting resorption of water independently of solutes, resulting in concentration of urine and dilution of blood serum. Its rate of secretion is regulated chiefly by the osmolarity of the plasma.

2. [USP], A pharmaceutical preparation of the same principle, prepared synthetically or obtained from the posterior pituitary of healthy domestic animals used for food by man; used mainly as an antidiuretic in the treatment of acute or chronic diabetes insipidus, administered intramuscularly as a test of hypothalamo-neurohypophysial-renal function in distinguishing central from nephrogenic diabetes insipidus; it may also be used to stimulate smooth muscle tissue, especially to induce vasoconstriction in the presence of hemorrhage. Called also antidiuretic hormone (ADH).

regulated

DEFINITION:

1. Having been adjusted to a certain standard.

2. In biology, describing the adaptation of form or behavior of an organism to changed conditions.

water channel

DEFINITION:

A channel in the plasma membrane of plant and animal cells that permits passage of water molecules; chemical substances such as vasopressin cause the opening of new channels and increase permeability.

aquaporin 2

DEFINITION:

Also called WCH-CD, this water channel makes the principal cells of the inner medullary collecting duct in the kidneys more permeable to water. Lack of functional aquaporin-2 gene leads to a rare form of nephrogenic diabetes insipidus.

chronic

DEFINITION:

Persisting over a long period of time.

regulation

DEFINITION:

1. The act of adjusting or state or being adjusted to a certain standard.
2. In biology, the adaptation of form or behavior of an organism to changed conditions.
3. The power to form a whole embryo from stages before the gastrula.

body water balance

DEFINITION:

See fluid balance.

multiple

DEFINITION:

1. More than one.

2. Occurring in or affecting various parts of the body at once.

3. The product of a quantity by an integer.

water balance disorders

DEFINITION:

Disorders caused by the disproportional relationship between the body's ingestion and excretion of water and electrolytes.