membrane receptors

DEFINITION:

Receptors located on or in the membrane of cells; called also cell-surface receptor .

guanine

DEFINITION:

A purine base, in animal and plant cells usually occurring condensed with ribose or deoxyribose to form the nucleosides guanosine and deoxyguanosine; these nucleosides are components of nucleic acids and of free nucleotides important in metabolism. Symbol G.

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.

binding protein

DEFINITION:

See under proteins.

GPCRs

DEFINITION:

G-protein-coupled receptors.

proteins

DEFINITION:

Any of a group of complex organic compounds which contain carbon, hydrogen, oxygen, nitrogen, and usually sulfur, the characteristic element being nitrogen, and which are widely distributed in plants and animals. Proteins, the principal constituents of the protoplasm of all cells, are of high molecular weight and consist essentially of combinations of a-amino acids in peptide linkages. Twenty different amino acids are commonly found in proteins, and each protein has a unique, genetically defined amino acid sequence which determines its specific shape and function. They serve as enzymes, structural elements, hormones, immunoglobulins, etc., and are involved in oxygen transport, muscle contraction, electron transport, and other activities throughout the body, and in photosynthesis.

binding protein - any of a number of plasma proteins (See below) that bind to hormones of low solubility (chiefly the thyroid and steroid hormones), thus providing a transport system for them; some are specific for particular hormones, while others bind to any sparingly soluble hormones. Called also carrier protein or transport protein (See below).

carrier proteins - A binding protein (See above).

plasma proteins - The hundreds of different proteins present in blood plasma, including carrier proteins (such as albumin, transferrin, and haptoglobin), fibrinogen and other coagulation factors, complement components, immunoglobulins, enzyme inhibitors, precursors of substances such as angiotensin and bradykinin, and many other types of proteins.

transport protein - binding protein (See above).

genome

DEFINITION:

1. The complete gene complement of an organism, contained in a set of chromosomes in eukaryotes, a single chromosome in bacteria, or a DNA or RNA molecule in viruses.

2. The full set of genes in an individual, either haploid (the set derived from one parent) or diploid (the double set, derived from both parents). In a human being the haploid set contains about 3 billion base pairs of DNA and 50,000-100,000 genes.

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.

genetic

DEFINITION:

1. Relating to or determined by the origin, development, or causal antecedents of something.

2. Of, relating to, or being a gene.

GPCRs

DEFINITION:

G-protein-coupled receptors.

clinical phenotype

DEFINITION:

The clinical expression of a single gene or gene pair.

congenital nephrogenic diabetes insipidus

DEFINITION:

A condition involving the kidneys (see nephrogenic diabetes insipidus) which exists at, and usually before, birth. Congenital refers to conditions that are present at birth, regardless of their causation.

linked

DEFINITION:

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

putative

DEFINITION:

1. Commonly accepted or supposed.

2. Assumed to exist or to have existed.

mutations

DEFINITION:

1. Changes in form, quality, or some other characteristic.

arginine vasopressin

DEFINITION:

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

AVP

DEFINITION:

Arginine vasopressin.

V

DEFINITION:

Valine; vanadium; vision; volt; volume.

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.

mutant receptors

DEFINITION:

Molecular structures within or on the surface of cells which do not bind with the specific substance for which they are intended, or do not cause the specific physiologic effect that accompanies that binding. See receptor.

endoplasmic reticulum

DEFINITION:

An ultramicroscopic organelle of nearly all cells of higher plants and animals, consisting of a more or less continuous system of membrane-bound cavities that ramify throughout the cytoplasm of a cell.

antagonists

DEFINITION:

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

V

DEFINITION:

Valine; vanadium; vision; volt; volume.

vascular

DEFINITION:

Pertaining to vessels, particularly blood vessels, or indicative of a copious blood supply.

pituitary

DEFINITION:

1. Hypophysial.
2. Hypophysis.
3. A preparation of some part of the pituitary gland of animals (e.g., cattle, pigs, sheep), used therapeutically.

AVP

DEFINITION:

Arginine vasopressin.

receptors

DEFINITION:

See definitions under "receptor."

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.

polymorphism

DEFINITION:

The quality or character of occurring in several different forms.

AVP

DEFINITION:

Arginine vasopressin.

receptors

DEFINITION:

See definitions under "receptor."

genetic

DEFINITION:

1. Relating to or determined by the origin, development, or causal antecedents of something.

2. Of, relating to, or being a gene.

arterial

DEFINITION:

Pertaining to an artery or to the arteries.

hypertension

DEFINITION:

Abnormally high blood pressure and especially arterial blood pressure.