3.paracrines: local hormones
What are the four principal avenues of cell to cell communication?
1.distant (endocrine): travels far, can affect specific organ or all tissues (general)
2.local (juxtacrine): usually to adjacent cells
3.self (autocrine): usually to surface of membrane
What are the different types of cell signaling?
the glands, tissues and cells that secrete hormones into the blood stream
-head: pineal gland, hypothalamus, pituitary gland
-throat: thyroid gland, parathyroid glands, thymus
-abdomen: adrenal gland, pancreas
-genitals: gonads (ovary, testis)
What are the major hormone sources of the endocrine system?
What else secretes hormones but are usually not thought of as glands?
1.secrete products by way of duct into an epithelial surface (ex:skin, GI tract, suduriferous;sweat, sebaceous;oil)
2.has extracellular effects, usually an enzyme (ex: breaking down of food)
1.ductless and release secretions into the blood stream
2.has intracellular effects (alter cell metabolism)
Exocrine glands vs. Endocrine glands
1.liver: bile salts to break down fats
2.pancreas: all other enzymes to break down fats, sugars etc.
3.stomach: produces gastrolipase, pepsin, H+ (by parietal cell)
4.SI: duodenum,jejunum, illium
What are the exocrine functions of the GI tract?
What is another name for the anterior pituitary?
What is another name for the posterior pituitary?
-hormones produced by the hypothalamus (8)
-6 regulate the anterior pituitary
1.releasing: stimulate pituitary cells to secrete own hormones
2.inhibiting: suppress pituitary secretion
-2 stored in the posterior pituitary to be released on demand (ADH, OT)
1.TRH: thyrotropin-releasing hormone
2.CRH: corticotropin-releasing hormone
3.GnRH: gonadotropin-releasing hormone
4.GHRH: growth hormone-releasing hormone
5.PIH: prolactin-inhibiting hormone
What are the releasing and inhibiting hormones of the hypothalamus?
promotes secretion of thyroid-stimulating hormone (TSH) and prolactin (PRL)
Thyrotropin-Releasing Hormone (TRH)
promotes secretion of aderenocorticotropic hormone (ACTH)
Corticotropin-Releasing Hormone (CRH)
promotes secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH)
Gonadotropin-Releasing Hormone (GnRH)
promotes secretion of growth hormone (GH)
Growth Hormone-Releasing Hormone (GHRH)
Inhibits secretion of prolactin (PRL)
Prolactin-Inhibiting Hormone (PIH)
Inhibits secretion of growth hormone (GH) and thyroid-stimulating hormone (TSH)
1.FSH: follicle stimulating hormone
2.LH: luteinizing hormone
3.TSH: thyroid-stimulating hormone
4.ACTH: adrenocorticotropic hormone
6.GH: growth hormone (Somatropin)
What are the hormones of the anterior pituitary gland?
-target organ/tissue: ovaries, testes
*female: growth of ovarian follicles and secretion of estrogen
*male: sperm production
Follicle Stimulating Hormone (FSH)
-target organ/tissue: ovaries, testes
*female: ovulation (oogenesis), maintenance of corpus luteum
*male: testosterone secretion (spermogensis)
Luteinizing Hormone (LH)
-target organ/tissue: thyroid gland
-effects: growth of thyroid, secretion of thyroid hormone
Thyroid-Stimulating Hormone (TSH)
-target organ/tissue: adrenal cortex (adrenal gland)
-effects: growth of adrenal cortex, secretion of glucocorticoids
Adrenocorticotropic Hormone (ACTH)
-target organ/tissue: mammary glands, testes
*female: milk synthesis
*male: increased LH sensitivity
-mainly producded at night in periodic matter (through vision)
-target organ/tissue: liver, bone, cartilage, muscle, fat
-effects: widespread tissue growth, esp in stated tissues
Growth Hormone (GH)
1.ADH: antidiuretic hormone (vassopressin)
What are the hormones of the posterior pituitary gland?
-released in response to bp/volume
-target organ/tissue: kidneys
-effects: water retention in kidneys
Antidiuretic Hormone (ADH)
-target organ/tissue: uterus, mammary glands
-effects: labor contractions, milk release
*possibly involved in ejaculation, sperm transport, sexual affection and mother-infant bonding
timing and amount of pituitary secretion is regulated by:
2.other brain centers
3.feedback from the target organs
Pituitary Hormone Regulation
-the release of hormones in response to signals from the nervous system
-controls posterior pituitary
1.steroid hormones: dervived from cholesterol. hydrophobic
2.biogenic amines (monoamines): made from amino acids and retain amino group. includes some neurotransmitters
3.peptide and protein hormones: chains of 3-200+ amino acids.
-oligopeptides: 3-10 amino acids
-polypeptides:10+ amino acids
-glycoproteins: protein-carb complexes
What are the 3 chemical classes of hormones?
Which hormones fall under steroid hormones?
-active form of vitamin D
-gotten from diet, skin (cholesterol and UV)
-causes serum Ca levels to drop
1.causes osteoblastic activation and osteoclastic inhibition
2.Ca absorption in SI and Ca reabsorption in kidney
3.takes Ca in blood into the bone
1.inactive vit D goes to liver
3.goes to kidney and vit D is activated
-increases glucose in blood
-inhibits immune system/inflammation
Which hormones fall under biogenic amines?
-affects lanocytes and circadian rhythms
Which hormones fall under oligopeptides?
responsible for stimulating the digestion of fat and protein
8.melanocyte stimulating hormone (MSH)
Which hormones fall under polypeptides?
-inhibits osteoclast activity
-major antagonist of PTH
-reduces Ca in blood
sugar bringing cell
-created by parathyroid gland
-master regulator of Ca in level in blood/serum
-causes kidney to dump phosphate into urine
-when Ca drops, PTH is induced:
1.increases resorption of Ca in kidney and intestines/GI tract
2.increases activity of osteoclasts
Parathyroid Hormone (PTH)
-They stimulate the production and release of melanin (melanogenesis) by melanocytes in skin and hair. MSH signals to the brain have effects on appetite and sexual arousal
-skin controls MSH maturity by sensing skin damage
- does not need control
Melanocyte Stimulating Hormone (MSH)
Which hormones fall under glycoproteins?
goes from kidney to bone marrow to stimulate hemopoietic stem cells to create red blood cells
-chemical signals released into the tissue fluid (NOT blood)
-diffuse only to nearby cells in the same tissue
-part of the family of paracrine secretions
-derived from arachidonic acid
What are two Eciodanoids?
-inactive enzyme precursor
-requires biochemical change for activation
-used in pancreas (pancreititis) and stomach (ulcers) to prevent enzymes from eating away at tissues/fat
Vitamin B12 is mainly absorbed by what part of the small intestines?
plasma and proteins
What are the components of blood?
What are the components of plasma?
remove blood, plasma and clotting proteins
What are the components of serum?
caused by too little T4
Congenital Hypothyroidism (Cretinism)
-results in deficiency of dietary iodine
-swelling of the neck
-w/o iodine, the thyroid cannot synethesize TH so the pituitary gland receives no feedback and acts as if the thyroid were under stimulated. extra TSH is produce and stimulate hypertrophy of the thyroid
-excess cortisol due to:
1.ATCH hypersecretion by the pituitary
2.ACTH secreting tumors
3.hyper activity of the adrenal cortex independently of ACTH
-disrupts carb and proten metabolism which leads to hyperglycemia, hypertension, muscular weakness and edema
-symptoms: buffalo hump, moon face
-an autoimmune disease
-adrenal glands are destroyed so cannot produce cortisol
-pituitary gland tries to compensate but since there is no adrenal gland, MSH is made
-sypmtom: skin turns brown
-is a hormone gland
-secretes Human Choronic Gonadotropin (HCG)
-stimulates and produces estrogen and progesterone in increasing manner
-is necessary to main pregnancy
Hypothalamus Pituitary Axis
-estrogen and progesteron receptor negatives cannot be controlled in cancer
-adrenline is released during stress:
-outer: adrenal cortex: corticol steriods (mainly cortisol)
-inner: medulla: 90% epinephine/10% norephinephrine
What is the hormone secreted by the outer and inner adrenal gland?
strength of contractions
rate of contractions
build up of fluid in the body
What are one of the usual symptoms of congestive heart failure?
What kind of drugs are usually used in congestive heart failure?
-thyroxin: T3 and T4
-T3: more active but produced less
-T4: less active but produced more
What hormones are produced by the thyroid gland?
increase cell metabolism in the body
What is the function of T4?
-hypothyroidism: idoine defiecency
-goiters, tired/sleepyness, cold senstivity
What happens when there is too little T4?
-atrial fibrillation: increased heart rate
-hyper, sweaty, heat sensitive
What happens where there is too much T4?
-usually damaged by alcohol
-has endocrine (in blood) and exocrine(in gall bladder) functions
-inflammation of gall bladder (due to gall stone blockages)
-CCK in stomach senses fats in stomach and SI, causes gall bladder to contract
-usually get a cholicytoectomy as solution
-usually affects: females, fat, 40, fertile, american indians
to produce insulin through beta cells
What is the main function of the pancreas?
allows sugar/glucose molecules to enter cells for energy/cell function
What is the function of insulin?
-immune system attacks beta cells so insulin cannot be produced
Type I Diabetes
-blocks insulins affects at the cells
Type II Diabetes
-vitamins that need fat to be activated
-vit A, D, E
What are fat soluble vitamins?
-mutation in fetus (tetrogenic)
What can too much Vitamin A cause?
-high density lipoprotein
-mostly protein, less fat
-absorbs fat in body as it moves along
-low density lipoprotein-
-mostly fat, less protein
-distributes fat throughout the body
above heart, sits between lungs (mediastinum)
Where is the thymus located?
-not really an endocrine gland
-does noy secrete factors
-main function is for T-cell maturation
-teaches diff btwn self and non-self (tolerance)
an autoimmune disease where they attack own cells because there is no tolerance
What does failure of of thymus lead to?