1. Heart
1.1. Stress Hormones
1.1.1. Atrial Natriuretic Peptide (ANP)
1.1.1.1. synthesized and secreted by cardiac muscle cells in walls of atria
1.1.1.2. when blood Na+ levels and pressure incr. > ANP binds to receptor in kidney and blood vessels > promotes salt excretion > lowers blood volume and relaxes vessel
1.1.1.3. controls electrolyte homeostasis
1.1.1.4. Target: kidneys, cardiovascular system
1.2. Negative Feedback Loops
1.2.1. low cortisol levels > hypothalamus releases corticotrophin-releasing hormone (CRH) (central stress hormone) > pituitary gland releases ACTH into blood > excess amount of hormone in adrenal gland = incr. in cortisol production = incr. cortisol blood levels > cortisol blocks CRH from hypothalamus + adrenocorticotropic hormone from pituitary > ACTH levels decr. = cortisol levels decr.
2. Hypothalamus
2.1. Maintains homeostasis: controls release of hormones from pituitary gland
2.2. Neurohormones: made by neurons in hypothalamus; diffuse into blood > pituitary gland > controls other endocrine glands with release of other hormones
2.3. Male Reproductive Hormones
2.3.1. GnRH: stimulates production of FSH and LH
2.3.1.1. Target: anterior pituitary
2.3.2. Spermatogenesis
2.4. Female Reproductive System
2.4.1. Gonadotropin Releasing Hormone (GnRH): released every 50-120 minutes; stimulates the pituitary gland to produce FSH and LH and release into the bloodstream
2.4.1.1. Target: pituitary
3. Pancreas
3.1. Blood Glucose Regulation
3.1.1. Peptide
3.1.1.1. Insulin: lowers blood glucose level by instructing target cells to take glucose from blood; secreted by beta cells
3.1.1.1.1. Targets: liver
3.1.1.2. Glucagon: raises blood glucose levels by stimulating breakdown of glycogen > glucose in liver; secreted by alpha cells; stimulates breakdown of fats > fatty acids + proteins > AA
3.1.1.2.1. Target: liver
3.1.1.2.2. stimulates liver gluconeogenesis (AA + non carbs converted to glucose
3.1.2. Negative Feedback Loops
3.1.2.1. alpha + beta cells in pancreas respond to changes by either incr./decr. insulin production and/or glucagon production to achieve homeostasis
3.1.2.1.1. High blood glucose > stimulates beta cells to incr. production of insulin + alpha cells decr. glucagon production > blood glucose levels decr.
3.1.2.1.2. Low blood glucose > stimulate beta cells to decr. production of insulin + alpha cells incr. glucagon production > blod glucose levels incr.
4. Adrenal Cortex
4.1. Stress Hormones
4.1.1. Steroids
4.1.1.1. Cortisol (glucocorticoids)
4.1.1.1.1. Target: everywhere; muscle, liver adipose cells
4.1.1.1.2. released from adrenal cortex through the zona fasciculata layer; hypothalamus-pituitary axis regulates production and secretion
4.1.1.1.3. incr. blood glucose by promoting breakdowns of fats + proteins; controls sleep/wake cycle and helps energy boosts
4.1.1.2. Aldosterone (mineralocorticoids)
4.1.1.2.1. produced in cortex of adrenal glands; part of the renin-angiotensin-aldosterone system
4.1.1.2.2. water balance; water reabsorption
4.1.1.2.3. Target: Kidneys (absorbs Na+ in blood + release K+ into urine; regulates blood pH)
4.2. Blood Glucose Regulation
4.2.1. Steroid
4.2.1.1. Cortisol: provides body with glucose by tapping into protein stores via gluconeogenesis in liver; can lead to incr. blood sugar levels
4.2.1.1.1. Targets: liver
4.2.1.1.2. stimulates liver gluconeogenesis
5. Adrenal Medulla
5.1. Stress Hormones
5.1.1. Amines
5.1.1.1. Norepinephrine
5.1.1.1.1. Noradrenaline: incr. BP; blood vessels narrow + blood pumped faster
5.1.1.2. Epinephrine/Norepinephrine
5.1.1.2.1. BOTH: restrict kidney function during stress by constricting blood vessels
5.1.1.2.2. incr. heart rate + force heart contractions; incr. blood flow to muscles + brain; incr. metabolic rate; control squeezing blood vessels (maintain BP)
5.1.1.2.3. Short term stressful situations; fight or flight response
5.1.1.2.4. Target: receptor sites in PM (whole body)
5.1.1.3. Epinephrine
5.1.1.3.1. Adrenaline: heart rate (faster breathing)
5.2. Blood Glucose Regulation
5.2.1. Adrenaline/Noradrenaline: incr. blood sugar levels by promoting conversion of glycogen > glucose; incr. heart rate and contractility of heart
5.2.1.1. Target: liver
6. Pituitary Gland
6.1. Secretes major hormones; located in Cranium (below brain); to major lobes: Anterior Lobe & Posterior Lobe
6.2. Neurohormones travel through portal vein that connects capillaries inside hypothalamus to capillaries inside pituitary gland
6.2.1. Hormones released by endocrine cells enter bloodstream to reach target tissue
6.3. Anterior Pituitary
6.3.1. Metabolic Hormones
6.3.1.1. Peptide
6.3.1.1.1. Growth Hormone (GH)/ Somatotropin
6.3.2. Stress Hormones
6.3.2.1. ACTH
6.3.2.1.1. long term stressful situations
6.3.2.1.2. stimulates production of corticosteroids, mineralocorticoids, glucocorticoids
6.3.3. Male Reproductive Hormones
6.3.3.1. LH: stimulates testosterone production from interstitial cells of testes (Leydig cells)
6.3.3.1.1. Target: steroli cells (testes)
6.3.3.2. FSH: testicular growth; sustain maturing sperm cells
6.3.3.2.1. Target: leydig cells (testes)
6.3.4. Female Reproductive System
6.3.4.1. Peptide
6.3.4.1.1. Follicle Stimulating Hormone (FSH): stimulates development of the maturing ovarian follicle and controls ovum production
6.3.4.1.2. Prolactin (PRL) : milk production; development of mammary glands within breast tissues
6.3.4.1.3. Luteinizing Hormone (LH): aid in egg maturation and provides the hormonal trigger to cause ovulation and the release of eggs from the ovary
6.3.4.1.4. Thyroid-stimulating Hormone (TSH): stimulates thyroid to release thyroxine (incr. metabolic rate, regulates growth and development)
6.3.4.1.5. Adrenocorticotropic Hormone (ACTH): stimulates adrenal cortex to release hormones (glucocorticoids)
6.4. Posterior Pituitary
6.4.1. Stress Hormones
6.4.1.1. Peptide
6.4.1.1.1. Vasopressin (ADH)
6.4.2. Female Reproductive System
6.4.2.1. Oxytocin: released in large amounts during labour and controls contraction of the uterus during childbirth and lactation; stimulates uterine muscles to contract and increases the production of prostaglandins (further increases contractions)
6.4.2.1.1. Target: posterior pituitary gland
7. Kidney
7.1. Blood Calcium Regulation
7.1.1. Vitamin D
7.1.1.1. Steroid
7.1.1.1.1. Calcitriol: used to treat hyperparathyroidism (overactive parathyroid glands) and metabolic bone disease in those who have chronic kidney failure; treat/prevents low Ca2+ levels
8. Ovary
8.1. Oogenesis: process by which ovaries produce and release eggs/ova
8.2. Corpus Luteum
8.2.1. Female Reproductive System
8.2.1.1. Estrogen: steroid hormone that stimulates the maturation of sex organs during puberty; 2ndary characteristics: breasts/body hair/pelvis widening
8.2.1.1.1. Target: ovaries, vagina, uterus, breasts, endometrium
8.2.1.1.2. Positive Feedback Loops
8.2.1.1.3. Negative Feedback Loops
8.2.1.2. Progesterone: steroid hormone that prepares and maintains the uterus for the implantation of the fertilized egg and the subsequent growth and development of an embryo
8.2.1.2.1. Target: hypothalamus, pituitary, endometrium, uterus
8.2.1.3. Inhibin: involved in negative feedback control of FSH secretion (luteal phase)
8.2.1.3.1. Target: hypothalamus
8.2.1.4. Relaxin: inhibits uterus contractions until TOB; relaxes ligaments in pelvis and softens & widens cervix in prep for childbirth
8.2.1.4.1. Target: uterus
9. Testicles
9.1. Spermatogenesis: diploid cell that undergoes mitosis to form new spermatogonia; formation of mature functional spermatozoa
9.2. Male Reproductive Hormones
9.2.1. Androgen: male hormone
9.2.1.1. development of 2ndary sexual characteristics: body hair, voice change, bone/muscle, metabolism
9.2.1.2. Testosterone: made in testicles; reproductive and sexual function; acts on cells to make sperm; affects mood/sex drive
9.2.1.3. Inhibin: correlated with steroli cell function; sperm #, spermatogenesis status and negatively correlated with FSH
9.2.2. Negative Feedback Loop
9.2.2.1. rising testosterone levels acts on hypothalamus and anterior > inhibit release of GnRH, FSH, LH > sertoli cells produce inhibin (released when sperm count is too high) > inhibits release of GnRH + FSH > spermatogenesis slows down
10. Parathyroid Gland
10.1. Metabolic Hormones
10.1.1. Peptide
10.1.1.1. Parathyroid Hormone (PTH)
10.1.1.1.1. Targets: kidneys, bones, intestine
10.1.1.1.2. maintains appropriate balance of Ca2+ in the bloodstream in in tissues that depend on Ca2+ for proper functioning
10.1.1.1.3. PTH works directly on kidney to increase renal calcium reabsorption and decr. renal P3- reabsorption
10.1.1.1.4. Negative Feedback Loop
11. Thyroid Gland
11.1. Stress Hormones
11.1.1. Amine
11.1.1.1. Triiodothyronine (T3)
11.1.1.2. T3 and T4 hormones work together to regulate body's temp, metabolism, and heart rate; essential for body growth
11.1.1.2.1. Targets: cells in brain, bone, heart, muscle
11.1.1.3. Thyroxine (T4)
11.1.1.4. Negative Feedback Loop
11.1.1.4.1. Hypothalamus secretes thyrotropin-releasing hormone (TRH) > TRH stimulates pituitary gland to produce thyroid-stimulating hormones (TSH) > TSH stimulate thyroid gland to secrete hormones > when thyroid hormones are high enough, TRH + TSH stop production (w/o TRH, thyroid gland cannot secret hormones
11.1.2. Parafollicular Cells (C-cells)
11.1.2.1. Peptide
11.1.2.1.1. Calcitonin