Ch.11 Endocrine pt. 4- pineal & adrenal

What is the pineal gland regulated by?

Suprachiasmatic Nuclei (SCN)

what is melatonin made from? What does it require?

-melatonin is made from tryptophan

-requires melanopsin found in the ganglion cells of the retina

define stress

perceived threat to homeostasis

What are the Adrenal glands? What are they stimulated by?

1) Adrenal Medulla( Inner)→stimulated by Sympathetic Nervous System

2) Adrenal Cortex(Outer)→stimulated hormonally(hypothalamus & anterior pit)

Which organs do the Adrenal Medulla target? Which hormone does the Adrenal Medulla release?

heart, bronchioles, blood vessels

-releases Epinephrine & some NE

What are the 3 zones of the Adrenal Cortex? Which hormone does each zone release?

1) Zona glomerulosa→Aldosterone(mineralocorticoid)

2) Zona fasciculata→Cortisol (glucocorticoid)

3) Zona reticularis→Androgens(e.g. DHEA & Androstenedione)

“Good Friends Rule”

What type of hormone are the Adrenal Cortex hormones?

steroid hormones made from cholesterol

-lipid-based

Function of Aldosterone? What does it do during stress? What is its target organ?

1) regulates Na+ & K+ balance + water balance

2) regulate blood pressure

-during stress, Aldosterone & ADH retain water & Na+

-kidneys are the target organ

Functions of Cortisol?

1) regulate glucose metabolism

2) controls blood pressure BY permit action of E & NE around smooth muscle of blood vessels

3) reduces inflammation

4) allows for proper fetal development

Which organs do glucocorticoids(cortisol) target?

liver & muscle

function of Androgens?

supplement sex steroids

When stressed, what happens in terms of concentrations of GH, Glucagon, & Insulin?

Increases GH & Glucagon BUT decrease Insulin to mobilize energy stores & increase plasma concentration of glucose

When stressed, what hormone gives off pain-killing effects?

increase in Beta-Endorphins

Effects of Increased Cortisol in the Plasma during stress?

1) increased gluconeogenesis from liver

2) increased protein catabolism(bone+muscle)

3) induce insulin resistance(body wants to use more glucose)

4) inhibit immunity/non-essential functions(growth+reproduction)

How can Cortisol function as negative feedback?

1) tell hypothalamus to stop releasing CRH

2) tell anterior pituitary to stop releasing ACTH

Symptoms of Adrenal Deficiency

1) Low Blood pressure (bc cortisol needed for epinephrine)

2) low blood sugar (bc cortisol helps w/ glucose metabolism & actually increases glucose during stress)

What is Addison’s disease? Caused by?

-low cortisol & aldosterone levels

caused by:

1) autoimmune attack on adrenal OR

2) TB or tremors

Symptoms of Addison’s Disease? Treatments for it?

1) DARK SPOTS ON SKIN

2) fatigue

3) orthostatic intolerance

4) GI issues

5) muscle weakness

6) hypoglycemia

-Oral Corticosteroids

Explain how hyperpigmentation is caused in Addison’s disease.

primal adrenal insufficiency→low cortisol=no negative feedback→lead to increase in CRH from hypothalamus & ACTH from ant. pit. →ACTH binds to MSH(melanocyte-stimulating hormones)→more MSH=more melanin

What is Cushing’s Syndrome? Caused by?

-excess cortisol in blood

Causes:

1) tumor on Adrenal or Anterior Pituitary

Symptoms & treatment for Cushing’s Syndrome?

1) Osteoporosis(catabolism of bones)

2) weak muscles(catabolism of muscles)

3) redistribution of fat

4) increase blood pressure (bc too much cortisol=increase epinephrine)

5) hyperglycemia close to DIABETES

Treatment: 1) remove pituitary tumor

2) adrenalectomy

Cushing’s Syndrome vs. Cushing’s Disease

Cushing’s Syndrome→could be issue w/ primary, secondary, or tertiary structures

Cushing’s Disease→issue with secondary structure(ant. pit)