Endocrine vs. Exocrine
Whats the differnce bw endocrine and exocrine glands?
pancrease has both, pituaitary gland in brain
Hormones - Released directly into blood
What are Hormones?
Chemical Messengers
What are Amine Hormones?
Amine Hormones
What are Catecholimines?
Where are they Produced?
Dopamine - Hypothalamus
Epi and NE - adrenal medulla
What are Peptide Hormones?
What is Proinsulin?
What are Steroid Hormones?
Primarily produced by adrenal cortex and gonads (ovaries and testes)
Derived from cholesterol
How do the locations for steroid hormone receptors differ from peptide hormone receptors? Why?
Steroid Receptors - inside the cell becuase they can diffuse across the membrane
Peptide Receptors - found on the cell membrane, cant get across into cell due to nature
Hormone Metabolism
What does [Plasma] in the blood depend on?
The rate of secretion from the endocrine gland
The rate of removal from the blood
Path of a Hormone
Do hormones go to every cell?
No, Hormones have actions on only the cells that have receptors for them (allowing them to be highly specific)
Where are Peptides and Catecholamines receptors located?
receptors located on extracellular surface of target cell’s membrane (these hormones are hydrophilic)
Where are Steroid and Thyroid Hormone receptos located?
receptors are located intracellularly (these hormones are lipophilic)
alter gene expression - protein experession - cell function
What happens when a hormone binds to a receptor?
(quick and slow effects)
How do Water Soluble Hormones get to a cell?
What do they do once they bine
Water - Soluble Hormone in blood unbound to any protein
Know Step 6
Hormone binds to a receptor, activating proteins and causing the function of the cell to change
How do Water inSoluble Hormones get to a cell?
How is hormone secretion controlled?
Control of Hormone Secretion
How do Changes in [plasma] of mineral ions or organic nutrients affect hormone secretion?
What is an example of how hormones regulate plasma concentration of ion controlling it through negative feedback?
What is another example of how hormones regulate plasma concentration of ion controlling it through negative feedback?
Insulin stimulated by increase in blood glucose
Pancrease secretes insulin which goes to cells needing glucose for energy
This decreases blood glucose levels
Control of Hormone Secretion
How does Neurotransmitter release from neurons ending on endocrine cells affect hormone secretion?
Neuronal input to glands stimulate or inhibit hormone release
Mechanism of How NT affect hormone secretion
3
Control of Hormone Secretion
How does Another hormone acting on the endocrine cell affect hormone secretion?
Glucagon release from the pancreas increases in response to high blood glucose levels. When blood glucose drop, glucagon is no longer released. what type of mechanism of hormone regulation is this?
change in [plasma]
What are The Adrenal Glands?