Lecture 9 The Adrenal Gland

Which concept of stress involves psychological stressors

Reactive response

Which concept of stress associates a stimulus with danger and may cause PTSD or phobias

conditional response

which concept of stress anticipates a disruption in homeostasis

Anticipitory

How can stress impact disease

cause or worsen existing

the adrenal gland releases _________ into circulation

Catecholamines

What impacts does the release of catecholamines, epinephrine and norepinephrine have

constricts blood vessels, raises blood pressure, stimulates heart (stronger force, faster HR), inc BP, and inc blood glucose

What is the composition of the adrenals

cortex and medulla

What does the adrenal cortex secrete

mineralcorticosteroids, glucocorticosteroids, and androgens

What are the three layers of the adrenal cortex

glomerulosa, fasciculata, and reticularis

The innermost part, the medulla releases catacholamines (Epi/NorEpi) under the direct influences of what

Sympathetic nervous system

Which hormone: is the stress response and is released from the hypothalamus

Corticotropin-releasing hormone (CRH)

Which hormone is released from the anterior pituitary and stimulates the release of cortisol

Adrenocorticotropic hormone (ACTH)

where is cortisol released from

zona fasciculata

Cortisol provides a negative feedback loop, acting on the hypothalamus and pituitary to suppress the production of what

CRH and ACTH

Which type of receptor helps drive the production of hormones from cholesterol

G-couples

What is the outer layer of the Adrenal cortex

zona glomerulosa

what is the middle layer of the adrenal cortex

Zona fasciculata

what is the last layer of the adrenal cortex

Zona reticularis

what does the zona glomerulosa primarily produce

mineralocorticoid aldoserone

what does the zona fasciculata primarily produce

glucocorticoids cortisol, cortisone, and corticosterone

what does the zona reticularis primarily produce

estrogens and weak androgens

How does aldosterone impact ion transport

sodium retention, potassium and hydrogen excretion

the release of aldosterone is regulated by the ________________ system

renin-angiotensin-aldosterone

The RAS is activated by what conditions

low sodium and water, inc K+, and dec in blood volume

What is the primary stimulant of aldosterone synthesis and secretion

Angiotensin II

In the Renin-Angiotensin system when the kidneys register that blood pressure is low what releases renin into the bloodstrem

Juxtaglomerular appartus

What does renin convert angiotensinogen to

angoitensin I

Angiotensin I circulates in the lungs where what enzyme in the capillaries covert angiotensin I to angiotensin II

Angiotensin-converting enzyme (ACE)

What physiological effects does angiotensin II have on the body

casuses vasoconstricition which inc blood pressure and stimulates the adrenal glands to release aldosterone which in the kidneys promotes reabsorption of sodium and water increasing blood volume and blood pressure

What are the Glucocorticoid hormones

cortisol, cortisone, and corticosterone

Where are the primary effects of the release of glucocorticoid hormones

inc blood glucose, causes protein breakdown, anti-inflammatory

What is the most potent naturally occurring glucocorticoid

Cortisol

What are the effects of cortisol on the immune sustem

Supresses function

What are the effects of cortisol on the Liver

Gluconeogenesis

What are the effects of cortisol on the Muscles

protein catabolism

What are the effects of cortisol on adipose tissue

Lipolysis

What are the effects of cortisol on cardiovascular system

inc myocardial contractility, inc cardiac output, inc blood pressure

The zona reticularis secretes

adrenal androgens and estrogens

What effects does the release of catacholamines have

inc blood glucose levels, inc heart rate, inc cardiac outout

Which cells in the adrenal medulla sercrete catacholamines epinephrine and norepinephrine

Chromaffin

Which hormone:
increases salt and water reabsorption in the kidneys. Also increase potassium secretion in the kidneys

aldosterone

Which hormone:
Increases blood sugar and the catabolism of triglycerides and protein
Has anti-inflammatory and immunosuppressive effects

Cortisol

Which hormone:
maintains blood vessel tone and blood pressure
helps determine male characteristic during fetal development and puberty

Androgens

For which part of the adrenal gland is their no known hypofunction

adrenal medulla

Disorder characterized by excessive aldosterone secretion by the adrenal cortex

Hyperaldosteronism

Primary hyperaldosteronism is characterized by what

hypertension and hypokalemia

In primary hyperaldosteronism pts have increased aldosterons and low _______

plasma renin levels

Whata re the most common causes of hyperaldosteronism

adrenal adenomas (conn’s syndrome) and bilateral adrenal hyperplasia

what causes cushing syndrome

excess cortisol

Chronic cortisol levels regardless of the cause

Cushing Syndrome

Overproduction of pituitary ACTH by a pituitary adenoma

Cushing disease

Caused by exogenous administration of glucocorticoids

Cushing-like syndrome

What is the most common cause of cushing syndrome

exogenous corticosteroid use

central obesity, moon face, buffalo humo, purple striae, hirsutism, acne, easu brusing, proximal muscle weakness, menstrual irregularities, depression/psychosis, hypertension, thirst, and polyuria

s/s of cushing syndrome

ACTH dependent etiologies (ACTH is elevated)

Pituitary overproduction and ectopic production

ACTH-independent etiologies (ACTH normal/low)

exogenous intake (most common) and adrenal overproduction

Adrenal insufficients primary, secondary, and tertiary causes

pathology of adrenal glands, lack of ACTH stimulation from pituitary, and lack of corticotropic releasing hormone from the hypothalamus

Primary adrenal insufficiency caused by rare auto immune mechanisms.
Has inadequate corticosteroid and mineralcorticoid synthesis + elevated ACTH

Addisons Disease

What are some clinical manifestations of addisons disease

hypocortisolism, hypoaldosteromonsn, weakness, hyperpigmentation, and vitiligo

Addisions diseease is caused by a primary deficiency of cortisol and aldosterone due to atrophy of what

Adrenal cortex

Pheochromocytoma are tumors derived of chromaffin cells that result in what

Adrenal medulla hyperfunction

What is the classic triad of a pheochromocytoma

headache, diaphoresis, and tachycardia in association with hypertension