VM 704 (Physiology)- Endocrine Physiology

Where are hormones secreted in the endocrine system of the liver?

The bloodstream

Where are hormones secreted in the exocrine system of the liver?

The gall bladder

Where are hormones secreted in the endocrine system of the pancreas?

The bloodstream

Where are hormones secreted in the exocrine system of the pancreas?

The pancreatic duct

What are the 6 categories of peptide hormones?

1. Hypothalamic-releasing hormones

2. Pituitary hormones

3. GI hormones

4. Pancreatic hormones

5. Calcitonin

6. Parathyroid hormone

How are peptide hormones created (3 main steps)?

Preprohormone > Prohormone > Hormone

What are the 4 main fatty acid hormones?

1. Prostaglandin

2. Prostacyclin

3. Leukotriene

4. Thromboxane

What is the one precursor molecule that produces almost all of the fatty acid hormones?

Arachidonic acid

What are the 4 main steroid hormones?

1. Cortisol/aldosterone

2. Testosterone

3. Progesterone

4. Vitamin D3

Do steroid hormones bind to cell-surface receptors or intracellular receptors?

Intracellular receptors.

What is the precursor molecule to steroid hormones?

Cholesterol

What are the 2 main types of amino acid hormones?

1. Tyrosine (Thyroid hormone, catecholamines)

2. Tryptophan (melatonin)

What is the anterior pituitary also known as?

The adenohypophysis

What is the posterior pituitary also known as?

The neurohypophysis

What is the suffix that follows every hormone released from the hypothalamus?

“Releasing-hormone (RH)”

What are the 2 hormones made by AND released by the posterior pituitary?

Oxytocin and vasopressin

What are the 5 main hormones made and released by the anterior pituitary?

1. Luteinizing hormone/follicle-stimulating hormone

2. Thyroid stimulating hormone

3. Growth hormone

4. Adrenocorticotropic hormone

5. Prolactin

What are the effects of the hormone oxytocin?

Milk release, uterine contraction, maternal instinct

How can oxytocin in the body be increased?

Physical or psychological stimulation

What is the effect of the hormone vasopressin?

Water/urine conservation

How is vasopressin regulated in the body?

Plasma osmolarity

What is the cause of central diabetes insipidus?

Lack of ADH from posterior pituitary gland

What is the cause of nephrogenic diabetes insipidus?

ADH is released, but kidney can’t respond to it

What are the effects of the hormone prolactin?

Milk production, stimulation of milk proteins

What is the primary inhibitor of prolactin?

Dopamine

What is the target organ of the HPA axis?

The adrenal gland

What is the pathway of the HPA axis?

Hypothalamus > (corticotropin releasing hormone) Anterior pituitary > (adrenocorticotropic hormone) Adrenal cortex > Cortisol

What are the 3 things released from the adrenal cortex?

1. Mineralcorticoids

2. Glucocorticoids

3. Sex steroids

What are the effects of cortisol (glucocorticoid)?

Fat breakdown, glucose uptake

Can you measure levels of releasing hormones on a bloodwork panel?

No

What is the main cause of Addison’s disease?

Damage to the adrenal cortex/adrenal glands.

What is the effect on the HPA axis of Addison’s disease?

Low cortisol (b/c adrenal cortex is damaged)

What are the 2 types of primary hyperadrenocorticism?

1. Pituitary-dependent

2. Adrenal tumor

What is the function of the mineralocorticoid aldosterone?

Salt release

What is the target organ of the HPT axis?

Thyroid gland

What hormones does the thyroid gland release?

T3 and T4

What ion does thyroid hormone depend on?

Iodine

What are the effects of thyroid hormone?

Increase in basal metabolic rate, development of fetal/neonatal brain

What are the main symptoms of hypothyroidism?

1. Obesity

2. Poor coat

3. Lethargy

4. Seeking heat

What are the main symptoms of hyperthyroidism?

1. Weight loss

2. Anger

3. Increased appetite