uric acid

DEFINITION:

The end product of purine catabolism in primates. Urate is very insoluble in water and disorders of purine metabolism produce gout, in which deposition of sodium urate crystals (tophi) in the joints and skin is followed by a foreign-body inflammatory response.

metabolism

DEFINITION:

1. The sum of all the physical and chemical processes by which living organized substance is produced and maintained (anabolism), and also the transformation by which energy is made available for uses of the organism ( catabolism ).

2. Biotransformation.

hormones

DEFINITION:

In the singular: 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 .

serum

DEFINITION:

1. The clear portion of any body fluid; the clear fluid moistening serous membranes.
2. Blood serum; the clear liquid that separates from blood on clotting.
3. Immune serum; blood serum from an immunized animal used for passive immunization; an antiserum, antitoxin, or antivenin.

uric acid

DEFINITION:

The end product of purine catabolism in primates. Urate is very insoluble in water and disorders of purine metabolism produce gout, in which deposition of sodium urate crystals (tophi) in the joints and skin is followed by a foreign-body inflammatory response.

hyperuricemia

DEFINITION:

Excess of uric acid or urates in the blood; it is a prerequisite for the development of gout and may lead to renal disease.

endocrine

DEFINITION:

1. Secreting internally; applied to organs and structures that release their products into the blood or lymph, and to substances (hormones) that exert specific effects on other organs.

2. Pertaining to internal secretions; hormonal.

disorders

DEFINITION:

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

hyperuricemia

DEFINITION:

Excess of uric acid or urates in the blood; it is a prerequisite for the development of gout and may lead to renal disease.

uric acid

DEFINITION:

The end product of purine catabolism in primates. Urate is very insoluble in water and disorders of purine metabolism produce gout, in which deposition of sodium urate crystals (tophi) in the joints and skin is followed by a foreign-body inflammatory response.

hypothyroidism

DEFINITION:

Deficiency of thyroid activity. In adults, it is most common in women and is characterized by decrease in basal metabolic rate, fatigue and lethargy, sensitivity to cold, and menstrual disturbances. If untreated, it progresses to full-blown myxedema. In infants, severe hypothyroidism leads to cretinism. In juveniles, the manifestations are intermediate, with less severe mental and developmental retardation and only mild symptoms of the adult form. When due to thyrotropin deficiency it is called secondary hypothyroidism.

hypoparathyroidism

DEFINITION:

The condition produced by greatly reduced function of the parathyroids possibly due to autoimmune disease or genetic factors, or by the removal of those bodies. The lack of parathyroid hormone leads to a fall in plasma calcium level--which may result in increased neuromuscular excitability and, ultimately, tetany--followed by a rise in plasma phosphate level. Bone turnover is reduced; there may also be dermatologic, ophthalmologic (cataracts), psychiatric, and dental symptoms, and associated primary failure of other endocrine glands, e.g., the adrenal cortex.

hyperuricemia

DEFINITION:

Excess of uric acid or urates in the blood; it is a prerequisite for the development of gout and may lead to renal disease.

renal

DEFINITION:

Pertaining to the kidney.

uric acid

DEFINITION:

The end product of purine catabolism in primates. Urate is very insoluble in water and disorders of purine metabolism produce gout, in which deposition of sodium urate crystals (tophi) in the joints and skin is followed by a foreign-body inflammatory response.

clearance

DEFINITION:

1. The process of clearing; the rate at which a substance is removed from the blood.

2. A quantitative measure of the rate at which a substance is removed from the blood; the volume of plasma that is completely cleared of the substance per unit time. Symbol C.

3. The space existing between opposed structures.

hypothyroidism

DEFINITION:

Deficiency of thyroid activity. In adults, it is most common in women and is characterized by decrease in basal metabolic rate, fatigue and lethargy, sensitivity to cold, and menstrual disturbances. If untreated, it progresses to full-blown myxedema. In infants, severe hypothyroidism leads to cretinism. In juveniles, the manifestations are intermediate, with less severe mental and developmental retardation and only mild symptoms of the adult form. When due to thyrotropin deficiency it is called secondary hypothyroidism.

central diabetes insipidus

DEFINITION:

See under diabetes insipidus.

nephrogenic diabetes insipidus

DEFINITION:

A syndrome of polyuria and hyposthenuria caused by the failure of the renal tubules to reabsorb water in response to antidiuretic hormone, without disturbance in the renal filtration and solute excretion rates; the condition does not respond to exogenous vasopressin. It may be inherited as a rare X-linked trait or be acquired as a result of drug therapy or systemic disease.

diabetic ketoacidosis

DEFINITION:

Diabetic acidosis.

renal

DEFINITION:

Pertaining to the kidney.

uric acid

DEFINITION:

The end product of purine catabolism in primates. Urate is very insoluble in water and disorders of purine metabolism produce gout, in which deposition of sodium urate crystals (tophi) in the joints and skin is followed by a foreign-body inflammatory response.

clearance

DEFINITION:

1. The process of clearing; the rate at which a substance is removed from the blood.

2. A quantitative measure of the rate at which a substance is removed from the blood; the volume of plasma that is completely cleared of the substance per unit time. Symbol C.

3. The space existing between opposed structures.

hypoparathyroidism

DEFINITION:

The condition produced by greatly reduced function of the parathyroids possibly due to autoimmune disease or genetic factors, or by the removal of those bodies. The lack of parathyroid hormone leads to a fall in plasma calcium level--which may result in increased neuromuscular excitability and, ultimately, tetany--followed by a rise in plasma phosphate level. Bone turnover is reduced; there may also be dermatologic, ophthalmologic (cataracts), psychiatric, and dental symptoms, and associated primary failure of other endocrine glands, e.g., the adrenal cortex.

secretion

DEFINITION:

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

antidiuretic hormone

DEFINITION:

See vasopressin.