Hypothalamic And Pituitary Relationsihps and Biofeedback 2 Flashcards
Suprarenal Glands
Adrenal Glands, since it is above the Kidney
Epi and NorEpi function and Class
Rapid response to stress (hypoglycemia, Exercise) Catecholamines
Cortisol Function and class
Chronic Stress, regulate glucose breakdown, immune homeostasis Glucocorticoid (steroid)
Aldosterone
Regulate salt and volume homeostasis Mineralcorticoid (steroid)
Dehydroepiandrosterone (DHEAS)
Androgen Precursor Steroid
Cortisol pathway
- Hypothalamus: releases CRH from circadian rhythm or stress 2. AP releases ACTH 3. ACTH goes to the Adrenal Gland= release Cortisol CORTISOL: immune suppression, gluconeogenesis, protein catabolism, Lypolysis
Cortisol Regulations
+: metabolic, physical, emotional stress, inflammation -: cortisol goes to hypo and AP
Where does ACTH bind on
On MC2R receptor on the Zona Fasciculata of the Adrenal Gland = CORTISOL (-feedback on Hypo and AP) If it binds to MC2R receptor on the Zona Reticularis of the Adrenal Gland =ANDROGENS (no negative feedback)
Cortisol and circadian rhythm
LOW: late evening HIGH: early morning
How is Aldosterone secretion regulated
- Low BP = Kidneys secrete RENIN *Liver: makes angiotensinogen 2. Renin converts angiotensinogen to Angiotensin 1 3. ACE: converts Angiotensin 1- Angiotensin 2 4. Angiotensin 2 goes to Adrenal Cortex= release ALDOSTERONE 5. Aldosterone goes to cytoplasmic R. and make proteins for ion channels 6. Causes Resorption of Na+ and H2O + excretion of K+ from kidneys 7. Increase BP
ACE
Angiotensin converging enzyme Also inhibits Bradykinin
Crushing syndrome Sx:
Truncal obesity (BACK OF NECK FAT+ABD) Moon face (ROUND FACE) Easy bruising PURPLE bruising HTN Edema Weakness Osteoporosis Diabetes Immunosuppressant Cognitive impairment
Dexamethasone Suppression Test LOW DOSE
Different pt. With CS and without CS(crushing syndrome) CS= no ACTH suppression
Dexamethasone Suppression Test HIGH DOSE
Distinguish pt. Both with CS (feeds back to the AP) CS caused by AP ACTH secretion tumor (is decrease in ACTH) or CS caused by NOT AP ACTH secretion tumor (no decrease in ACTH)
Excess Glucocorticoid causes + exogenous Glucocorticoid
Bone resorption Muscle protein breakdown Gluconeogenesis Obesity Decreased growth Insulin resistance And FA production Atrophy of adrenal gland = X cortisol
ACTH made in AP(from POMC)from other not adrenal cortex organs
Binds to the alpha-MSK R. that make MELANIN =can cause hyperpigmentation = Addison’s disease
Primary Adrenal insufficiency
ADDISONS DISEASE (due to excess ACTH) ACTH and RENIN does not bind effectively to Adrenal Gland *adrenal gland issue LOW CORTISOL AND ALDOSTERONE CAUSE: Autoimmune, Adrenal hemorrhage after meningitis or anticoagulant, TB, or tumor
Secondary/Teritary adrenal insufficiency
ACTH is not made by AP (no hyperpigmentation) *AP problem Renin can still bind and make aldosterone No CORTISOL
Adrenal Insufficiency Tx:
Replace the H. That Adrenal gland can’t make Cortisol ——> Corticosteroid (Hydrocortisone, prednisone, dexamethasone) Aldosterone——> mineralcorticoid (fludrocortisone) (only in primary)
Primary Adrenal Excess
HGIH CORTISOL LOW ACTH, LOW CRH No hyperpigmentation
Secondary Pituitary Excess
HIGH CORTISOL, ACTH, LOW CRH (hyperpigmentation)
Primary deficiency
LOW CORTIOL, ALDOSTERONE HIGH ACTH, CRH (hyperpigmentation)