ACTH, Glucocorticoids, and Androgens

Glucocorticoids

Type of steroid hormones used to treat various medical conditions, including glucocorticoid deficiency and autoimmune diseases.

Cushing's Disease

A condition caused by excessive cortisol production, often due to a pituitary tumor.

Congenital Adrenal Hyperplasia (CAH)

A genetic disorder affecting adrenal gland function, often characterized by a deficiency in cortisol and aldosterone.

Dexamethasone

A synthetic glucocorticoid drug known for its high potency and long-lasting effects.

Iatrogenic Cushing’s-like Syndrome

A condition resulting from chronic exposure to exogenous glucocorticoids, leading to symptoms similar to Cushing's.

21-Hydroxylase Deficiency

The most common cause of CAH, leading to the accumulation of steroid precursors and deficiencies of cortisol and aldosterone.

Polydipsia and Polyuria

Increased thirst and urination, commonly seen in dogs with Cushing's, possibly linked to ADH inhibition.

Trilostane

A medication used to treat Cushing's disease by inhibiting adrenal steroid biosynthesis.

Hypoadrenocorticism

A condition characterized by insufficient production of adrenal hormones, often referred to as Addison’s disease.

ACTH

Adrenocorticotropic hormone, a hormone produced by the anterior pituitary that stimulates adrenal cortex hormone synthesis.

Muscle wasting

A symptom of Cushing's syndrome characterized by loss of muscle mass.

Addison’s-like disease

A type of adrenal insufficiency commonly caused by prolonged glucocorticoid treatment, leading to signs such as hyperkalemia.

Adrenalectomies

Surgical removal of the adrenal glands, often performed to treat conditions like Cushing's.

Signs of Cushing's

Common symptoms include increased blood glucose, muscle wasting, truncal alopecia, and decreased bone density.

Cushing's Diagnosis

Diagnosis is determined by the presence of clinical symptoms, elevated cortisol levels, and an ACTH challenge.

Glucocorticoids

A class of steroid hormones produced in the adrenal cortex that regulate metabolism, immune response, and stress responses.

Androgens

Steroid hormones produced primarily in the zona reticularis of the adrenal cortex that influence male and female characteristics and reproduction.

ACTH

Adrenocorticotropic hormone, a pituitary hormone that stimulates the production of glucocorticoids and androgens in the adrenal cortex.

Zona fasciculata

The layer of the adrenal cortex that primarily secretes glucocorticoids, such as cortisol.

Zona reticularis

The inner layer of the adrenal cortex that primarily secretes androgens, such as dehydroepiandrosterone (DHEA).

Cortisol

A glucocorticoid hormone produced by the adrenal cortex, involved in metabolism regulation and stress response.

DHEA

Dehydroepiandrosterone, an androgen hormone produced by the zona reticularis, which can be converted to testosterone.

CRH

Corticotropin-releasing hormone, produced by the hypothalamus to stimulate the release of ACTH from the anterior pituitary.

Negative feedback

A regulatory mechanism where cortisol inhibits the release of CRH and ACTH to maintain homeostasis.

Addison's Disease

A condition caused by chronic deficiency of cortisol and mineralocorticoids, leading to elevated ACTH levels.

Cushing's Syndrome

A condition characterized by excessive cortisol production often due to a pituitary tumor, resulting in a constellation of symptoms.

Circadian rhythms

Biological processes that display an endogenous, entrainable oscillation of about 24 hours, influencing cortisol release.

Steroidogenesis

The process by which steroid hormones are generated from cholesterol.

Gland structure

The physiological organization of the adrenal glands, including the cortex and medulla.

Mineralocorticoids

A class of steroid hormones, such as aldosterone, that regulate sodium and potassium balance.

Adrenal gland

An endocrine gland located on top of each kidney responsible for producing hormones like cortisol, aldosterone, and androgens.