The cell signals itself through chemicals that it produced. It can be w/in the cytoplasm or on the surface of the cell.
Define Paracrine:
chemical signals that interact with receptors on nearby cells
Examples of Paracrine chamical signals are:
Cytokines and neurotransmitters
define exocrine:
chemical signals are secreted into ducts
define endocrine:
chemical signals are secreted into the blood
The nervous system compared to the endocrine system is:
fast and electrical
The endocrine system produces what?
chemical signals = hormones
Cells muct bear what to respond to a hormone?
receptor
T/F, some neurons can act as endocrine cells?
True
Define endocrinology:
The study of hormones and their signaling pathways
Endocrine organs include:
Hypothalamus
Pineal Gland
Pituitary Gland
Thyroid
Parathyroid
Pancreas
Adrenal Glands
Gonads
Diffuse endocrine system includes what specific types of cells:
Myocytes of heart atria
some epithelial cells
cells in stomach and small intestine
The diffuse endocrine system is classified as what type of endocrine cells?
Non-traditional
Non-traditional endocrine organs include:
Heart
GI tract
Kidney
Liver
Thymus
Non-traditional endocrine cells include:
Lymphocytes
Adipose
Endothelial cells
Macrophages
Fibroblasts
Cells that produce growth factors
GI hormonal regulation of motility
Motilin
Substance P
Neurotensin
Enteroglucagon
Vasoactive intestinal peptide
Motilin is involved with:
GI motility
Substance P is involved in:
GI motility
Neurotensin is involved in:
GI motility
Enteroglucagon is involved in:
GI motility
Vasoactive intestinal peptide is involved in:
GI motility
Amines are derived from:
Tyrosine
Steroids are derived from:
Cholesterol
Peptides have how many amino acids?
> 3
Hormone groups that are drived from tyrosine are:
Thyroid hormones and Catecholamines
What two amino acids (other than Tyrosine) are hormone precursors?
Tryptophan and Histadine
Examples of Catecholamines include what examples:
epinephrine
norepinephrine
dopamine
Example of a Thyroid hormone is:
Thyroxine
Thyroid hormones are usually made by:
doubling a tyrosine and incorporating 3-4 iodine atoms
The incorporation fo Iodine atoms into Thyroid hormones adds what characteristic?
Hydrophobicity
The differnce between epinephrine and norepinephrine is:
the methyl group attached to the nitrogen is removed and replaced with a hydrogen
Dopamine is different from norepinephrine how?
The OH group is changed to a Hydrogen.
How do Tyroxine and Triidothyronine differ?
Triidothyronine has one less iodine (T3)
Hormones undergo modifications during packaging and after they have been secreted T/F?
True
What is a pre-pro-hormone?
a hormone that has not been fully synthesized, packaged or stored.
insuline is synthesized as what type of hormone precursor?
pre-pro-hormone
Isulin is synthesized where?
B cells of the islets of Langerhans
The pre portion of a pre pro hormone is a:
signal peptide
The pre component of the prepro insulin is removed where?
cisternae of the endoplasmic reticulum
After the pre componenet of preproinsulin is removed what happens to the molecule?
it is packaged into secretory vesicles in teh Golgi
folded into its native structure
locked into this conformation by 2 disulfide bonds
Protease activity cleaves what portion of the pro-insulin molecule to form the final hormone?
Center third of the molecule
The cleaved center third of an insulin molecule is called?
C peptide
The final insulin product has what two chains wtill intact?
A and C chain
The A and C chain of an insulin molecule are held together by wht?
2 disulfide bonds
The amino terminal is on which peptide of insulin?
The B peptide
The carboxyl terminal is on which peptide of insulin?
The A peptide
insulin is differnt from proinulin by what characteristic?
The A, C and B chain with a signal peptide attached to the B chain.
Proinsulin has what parts?
A, C and B peptides with dislufide linkers (2) between the A and B components.
insulin is differnt from proinsulin by what parts?
No C peptide
The first three steps of steroid production are:
Signal for steroid production
Activation of cAMP
Protein Kinase A activation of cholesterol esterase
Steps 4-5of Steroid synthesis are:
4 & 5) Cholesterol transported by steroidenic acute regulatory protein to mitochondria
Dteps 6-9 of steroid synthesis are:
transport between mitochondria ER
diffusion via lipid bilayer to blood
PKA stands for
Protein Kinase A
LDL stands for
Low density lipoproteins
StAR stands for:
steroidenic acute regulator protein
PBR stands for:
peripheral-type benzodiazepine receptor
Sex steroid produced in the adrenal gland is:
Progesterone
Sex steroids produced in the Gonads are:
Androstenedione
Testosterone
Estradiol
Steroids of the adrenal gland are:
Progesterone
Corticosterone
Aldosterone
Mineral corticoid produced in the adrenal cortex is:
Aldosterone
Glucococorticoid produced in the adrenal gland is:
Corticosterone
Androstenedione is produced where?
Gonads
Androstenedione is what type of steroid?
Sex steroid
Testosterone is porduced where?
Gonads
Testosterone is what type of steroid?
Sex steroid
Estradoil is what type of steroid?
sex steroid
Estradoil is produced where?
Gonads
Progesterone is what type of steroid?
Sex steroid
Corticosterone is what type of steroid?
Glucocorticoid
Corticosterone is produced where?
Adrenal Cortex
Aldosterone is what type of steroid?
Mineralcorticoid
Aldosterone is produced where?
Adrenal cortex
Cholesterol can be converted directly into what three hormones?
Coricol
Progesterone
Androstenedione
Progesterone can be converted directly into what two steroids?
Corticol
Androstenedione
What are the intermediates between cholesterol and Aldosterone?
Pregnenolone
Progesterone
Corticosterone
What are the intermediates between Cholesterol and Cortisol?
Pregnenolone
17-Hydroxyprogesterone
What are the intermediates between Chlolesterol and Androstensdione?
pregnenolone
dehydroepiandrosterone
OR
Prenenolone
17-Hydroxyprogesterone
OR
Pregnenolone
Progesterone
17-hydroxyprogesterone
Aromatase converts Adnrostenedione into __________ in the gonads?
Estrone
Aromatase converts Testosterone into what in the Gonads?
Estradiol
What hormone is secreted by the testis?
Testosterone
What hormone is secreted by the ovaries?
Estradiol
Estrone can be converted into what hormone?
Estradiol
What are the two pathways for Estradiol production in the Gonads?
Cholesterol
Androstenedione
Estrone
Estradoil
OR
Cholesterol
Androstenedione
testosterone
estradiol
What is the pathway of testosterone porduction in the Gonads?
Cholesterol
Androstenedione
Testosterone
What are the two main areas of the adrenal gland?
Medulla (inner) and cortex (outer)
What are the three zones of the adrenal cortex?
Zona glomerulose (outer)
Zona fasciculata (middle)
Zona reticularis (inner)
What hormone is porduced in the Zona glomerulose of the adrenal gland?
Aldosterone
What hormone is produced in the Zona fasciculata of the adrenal gland?
Cortisol and small amounts of androgens
What hormones are produced in the Zona reticularis of the adrenal gland?
Androgens and small amounts of cortisol
What hormones are produced in the Adrenal Medulla?
Epinephrine and Norepinephrine
What types of hormones are water soluble?
Amino Acid derivative and peptides
What types of hormones are water insoluble?
Ateroids
Thyroxine
Triidothyronine
How are water insoluble hormones transported?
Protein carrier molecules
Hfree + Bprotein = H/BP
Maintenance of plasma levels of hormones controlled by three aspects, which are:
Rate of secretion
Rate of dispersal
Rate of removal
What is the most highly regulated aspect of endocrine control of hormone levels?
Rate of production: synthesis and secretion
Rate of delivery of a hormone is controlled by:
blood flow to the area
Rate of degredation and elimination of hormones is controlled by:
metabolism and excretion
If a half life for a hormone is long, what is the expected rate of secretion?
low
If the half life of a hormone is short what is the expectde rate of secretion?
Fast
What three things effect the rate of hormone secretion by an endocrine cell?
Ions or nutrients
neurotransmitters
hormones
Where are the protein recetors for water soluble hormones located on the cell?
Cellular membrane
Where are the protein receptors for lipid soluble hormones located on the cell?
Intracellularly
Describe the mechanism of action of a lipid soluble hormone on a cell:
Diffuse through cellular membrane and attach to intracellular receptor
Describe the mechanism of action of a water soluble hormone on a protein receptor?
bind to cellular membrane receptor
What four types of cell surface hormonal receptors exist?
those that function as ion channels as well
those that function as enzymes as well
those that are bound to and activate cytoplasmic JAK kinases
those that activate G proteins
G proteins act as what type of effector protein when activated?
ion channel or enzyme
What is the mechanism of action of lipid soluble hormonal receptors?
function in the nucleus as transcription factors or supressors
What is permissiveness?
Synergistic interactions
Give an example of permissiveness:
Epinephrin and thyroid hormone cause a synergistic interaction that causes the release of fatty acids from a cell at a rate that is much higher than the composite produced of each hormone on their own.
Give an example of an antagonizing hormone
Somatostatin acts on the anterior pituitary somatotrophic cells to inhibits the release of GH (growth hormone)
Somatostatin effects what cells?
Anterior pituitary somatotrophs
The action of Somatostatin on the anterior pituitary somatotrophs is classified as:
Antagonism
The action of epinephrine and thyroid hormone together of cells vs. each separetly is an example of:
permissiveness or synergistic interactions
Up regulation refers to what?
an increase in teh total number of target cell receptors for a hormone
Up regulation often happens due to what?
chronic low extracellular conc. of a hormone
chronic low extracellular conc. of a hormone can cause what?
up regulation
down regulation refers to what?
A decrease in the total number of target cell receptors for a given hormone
What causes down regulation?
Chronic high extracellular concentrations of the hormone
chronic high extracellular concentrations of a hormone can cause what?
down regulation
What are two type of receptor number modulations?
up and down regulation
Up and down regulation are what type of modulations?
receptor number modulations
What are the three segments of neuronal imputs for hormone regulation?
autonomic nervous system
Central nervous system
hypothalamus
What divisions of the autonomic nervous system play a role in hormonal regulation?
Adrenal medulla
Endocrine gland cells
What divisions of the central nervous system are involved in hormone regulation?
Autonomic nervous system and the hypothalamus
What divisions of the hypothalamus are involved in hormone regulation?
Anterior pituitary and the posterio pituitary
The hypothalamus interacts with the anterior pituitary via?
hormones
the hypothalamus interacts with the posterior pituitary via:
Direct electrical signal via neurons
The CNS interacts with the adrenal medulla via:
direct electrical signal via neurons
The CNS interacts with endocrine gland cells via:
neurons synapsed in the autonomic galnglion and then direct neural contact with the gland cell.
Types of endocrine disorders can be broken into two catagories:
endocrine gland secretion
target gland response
types of endocrine gland production disorders are:
hypersecretion and hyposecretion
types of target gland response disorders are:
hyporesponsive or hyperresponsive
Endocrine products are secreted and carried/delivered via:
the blood
Classes of hormones are (3):
amines
peptides
steroids
Water insoluble hormones require what for transport?
