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.

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).

secretion

DEFINITION:

The process of segregating, elaborating, and releasing some material either functionally specialized (as saliva) or isolated for excretion (as urine).

analysis

DEFINITION:

1. Separation into component parts or elements; the act of determining the component parts of a substance.

2. Psychoanalysis.

plasma osmolality

DEFINITION:

See individual entries for plasma and osmolality .

sodium

DEFINITION:

A silver white soft waxy ductile element of the alkali metal group that occurs abundantly in nature in combined form and is very active chemically.

functional

DEFINITION:

1. Of or pertaining to a function.

2. Affecting the function but not the structure.

properties

DEFINITION:

Properties are characteristic qualities, abilities, capabilities, or functions.

altered

DEFINITION:

1. Having been made or become different.

2. Castrated; spayed.

3. Abbreviation for "alteration."

reciprocal

DEFINITION:

1. Pertaining to the giving and receiving in exchange or to the complementary interaction of two distinct entities.
2. In dentistry, pertaining to the means by which one part of a removable partial denture framework is made to counter the effect created by another part of the framework.

antidiuretic

DEFINITION:

1. Suppressing the rate of urine formation.

2. An agent that suppresses urine formation.

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).

association

DEFINITION:

1. A state in which two attributes occur together either more or less often than expected by chance.

2. In neurology, a term applied to those regions of the brain that link the primary motor and sensory cortices; see association areas.

3. In genetics, the occurrence together of two or more phenotypic characteristics more often than would be expected by chance.

4. In psychiatry, a connection between ideas or feelings, especially between conscious thoughts and elements of the unconscious, or the formation of such a connection.

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.

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).

secretion

DEFINITION:

The process of segregating, elaborating, and releasing some material either functionally specialized (as saliva) or isolated for excretion (as urine).

modification

DEFINITION:

The process or result of changing the form or characteristics of an object or substance.

physiologic

DEFINITION:

Normal; not pathologic; characteristic of or conforming to the normal functioning or state of the body or a tissue or organ; physiological.

pathological

DEFINITION:

Pertaining to pathology.

endogenous

DEFINITION:

1. Growing from within.

2. Developing or originating within the organism, or arising from causes within the organism.

solute

DEFINITION:

A dissolved substance.

specificity

DEFINITION:

1. The quality or state of being specific.
2. The conditional probability that a person not having a disease will be correctly identified by a clinical test, i.e., the number of true negative results divided by the total number of those without the disease (which is the sum of the numbers of true negative plus false positive results).

insulin

DEFINITION:

A protein hormone secreted by the beta cells of the pancreatic islets that serves as a hormonal signal of the fed state; it is secreted in response to elevated blood levels of glucose and amino acids and promotes the efficient storage and utilization of these fuel molecules by controlling the transport of metabolites and ions across cell membranes and regulating various intracellular biosynthetic pathways. Insulin promotes the entry of glucose, fatty acids, and amino acids into cells; promotes glycogen, protein, and lipid synthesis; and inhibits gluconeogenesis, glycogen degradation, protein degradation, and lipolysis. Insulin secretion is also influenced by several gastrointestinal hormones and by autonomic nervous activity. Insulin is formed from a single polypeptide chain (proinsulin) that is cleaved by specific proteases at two points; the two end pieces (the A and B chains) held together by two disulfide bridges, make up insulin; the middle piece (the connecting peptide or C-peptide) is also secreted but has no physiologic activity. Relative insulin deficiency is the cause of most cases of diabetes mellitus. Exogenous insulin is used for control of diabetes; various preparations differ in regard to source (bovine, porcine, a mixture of the two, or recombinant human types), rapidity of onset and duration of action and degree of purification (most preparations contain some proinsulin and other antigenic components).

potency

DEFINITION:

The relationship between the therapeutic effect of a drug and the dose necessary to achieve that effect; a drug with a higher potency will require a smaller dose to produce a given effect. Clinically, potency has little use except as a means to compare the relative activities of pharmaceutic agents.

properties

DEFINITION:

Properties are characteristic qualities, abilities, capabilities, or functions.

disorders

DEFINITION:

Derangements or abnormalities of function; morbid physical or mental states.

water balance

DEFINITION:

Fluid balance.

abnormalities

DEFINITION:

1. The quality or fact of being abnormal.


2. Malformations, deformities, or anomalies.

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).

secretion

DEFINITION:

The process of segregating, elaborating, and releasing some material either functionally specialized (as saliva) or isolated for excretion (as urine).