C16 Endocrine system

What is cushing’s disease?

Too much cortisol

Causes fat deposits on face and back of neck

How are hormones classified, what are the differences

Amino acids: amines, thyroxine, peptides, proteins

Steroids: cholesterol, gonadal and adrenocortical (outer layer of adrenal gland

Steroids are non-polar and need a carrier. They go thru the cell membrane and activate genes or synthesis of proteins

Amino acids bind to a receptor, and activate g signal transduction

What are the mechanics of hormones to target cells

Change plasma memb. permeability

Stim making of proteins

Activate/deactivate enzyme syst

Secretary activity

Stim mitosis

What organs filter toxins

Liver (non polar toxins)

Kidneys (polar)

What hormones are produced by anterior vs posterior pituitary gland

What are the differences of tissues

Anterior: Made of mucosa/glandular,

TSH, prolactin, FSH, GH, LH, ACTH

Posterior: neural

ADH, oxytocin

What are steriod hormones derived from

Cholesterol

What hormone class use intercellular receptors always bound to the DNA

Thyroid amines

WHat hormones use a G protein linked receptor, and why

ACTH, Glucagon, TSH

Cannot enter target cells bc of polarity

What glands are neurally controlled

Pineal, adrenal medulla, posterior pituitary gland,

What area of brain regulates endocrine and ANS system?

Hypothalamus

WHat glands are in the CNS, what is secreded by themm

Pineal: melatonin

Pituitary: (anterior): GH

What is a tropic hormone, what is the pathway

Hormone that targets another endocrine gland, influences production of another hormone

Hypothalamus: TRH → Anterior pit: TSH → Thyroid gland: thyroid hormones

Hypothalamus: CRH → Anterior pit: ACTH → Adrenal cortex: cortisol

How are steriods transported thu blood, and hw do they enter target cell

Protein transport carriers, enter thru phospholipid bilayer of cell, and target protein synthesis thru gene activation

Endo vs exocrine glands

Endo: release into bloodstream (Pancreaus, thyroid, hypothalamus, pituitary, ect)

Exo: secrete thru ducts (sweat, saliva, pancreas : DIgestive enzymes)

Tissue types in glands:

Epithelial: simple cuboidal or columnar

Supported by connective tissue (areolar connective)- vascular, supportive

Major endocrine glands:

Hypothalamus
Pituitary

Pineal

Thyroid

Parathyroid

Adrenal

Pancreas

Gonads

Thymus (mainly childhood)

What other structures secrete hormones?

Heart (ANP)

Kidneys (erythropoietin, renin)

Adipose tissue (leptin)

GI tract (Gastrin, secretin)

Placenta

What are eicosanoids>

Local chemical messengers, lipid based

Paracrine: affect nearby cells, prostaglandins causing inflammation

Autocrine: Affect same cell that released them, immune cell signaling

Function: inflammation, blood clotting, pain, fever, smooth muscle contractions

What are g-linked receptors, what are the structure

What hormones use them

What are the responces

Membrane receptor

G protein (GDP - GTP)

Effector enzyme

Second messenger (cAMP, IP3)

Epinephrine, glucagon, TSH

Enzyme activation, ion channel opening, metabolic changes, rapid amplification

What influences target cell responce

What can effect the receptor number

Hormone contraception

Number of receptors

Affinity of receptors

Upregulation- low hormones

Down regulation- high hormones

What are the three types of hormone interactions

Permissive: 1 allows the other to act, more for development : Thyroid hormone and epinephrine

Synergistic: combined affect greater than sum, glucagon and epinephrine

Antagonistic: 1 opposes another, insulin vs glucagon

Results: enhanced, reduced, or blocked response

What controls hormone release?

Humoral stim: blood/ion nutrient levels

Low calcium levels in blood, PTH released

Hormonal stim: one hormone triggers another

TSH → thyroid hormones

Neural stim: nerve impulses

Ex: Sympathetic stim: triggers adrenal medulla to release glucagon

What glands are controlled neurally?

Adrenal medulla, posterior pituitary, pineal gland,

How does the hypothalamus communicate with pituitary gland?

How does the tissue differ

ANterior: thru the portal blood system, the hypothalamus rleases hormones that travel down infundibulum, and diffuse across to pituitary

Posterior: through neurons

Glandular vs neural

how do the anterior vs posterior pituitary differ in hormone release or syntheiss

anterior: produces its own hormones that regulate body functions

Posterior: stores and releases hormones synthesized by hypothalamus

What are some non-tropic hormones

GH, prolactin (PRL)

Both affect tissues

role of the pancreas

Digestive function (exocrine)- releases enzymes to break food down

Blood sugar regulation:

Insulin: lowers by helping cells take in glucose

Glucagon: raises by signaling liver to release glucose

Somatostatin: reguluation

Role of parathyroid glands

Regulate calcium

Secrete PTH to raise blood calcium levels:

Bones: osteoclast

Kidneys: reabsorption

Intestines: calcium absorption from food

role of thymus

immune system development, especially in kids

Produces thymosin, thymopoietin, thymulin

Guide t cell development

T cells help fight viruses/ bacteria, cancer

adrenal cortex role

Long term regulation of metabolism, stress, electrolytes:

Steroid hormones:

Aldosterone: increases BV and BP, brings Na in, H2O follows

Cortisol: Metabolism, increases blood glucose, and antiinflammatory

Androgens: Puberty, sex hormones

Adrenal medulla role

Fight or flight

Epinephrine, norepinepherine

Inc. HR and BP, mobilizes glucose and fat

Ovaries/testes role

Estrogen/testosterone: 2nd sex characteristics, spermatogenisis, oogenisis

Progesterone: regulates uterus

Both: produce inhibin, regulates FSH

Both are responding to FSH: gamate production, and LH sex hormone production