What is a hormone?
- endocrine system
- travels through the bloodstream
- slow speed of communication
- released into bloodstream, binds to receptors
What is a neurotransmitter?
- NS
- travels through synapses
- rapid speed of communication
- AP releases NT to bind to receptor creating a graded potential
Where are hormones produced?
in glands or wishing cells of an organ
What are the characteristics of peptides/ proteins?
- hypothalamic pituitary hormone
- AA
- hydrophillic
- dissolves in the blood
- receptors on plasma membrane
- fast time before onset of action
What are the characteristics of steroids?
- testosterone, estrogen, cortisol
- cholesterol
- lipophillic
- use blood protein carriers to travel in blood
- location of receptor is intracellular
- slow onset of action
What are the characteristics of amines?
- catecholamines (epinephrine, T3, T4)
- tyrosine
- both lipophilic and hydrophilic
- dissolves in blood and uses protein carriers
- location of receptor in plasma membrane and intracellular
- fast and slow onset of action
What is the anterior pituitary gland made of?
endocrine cells
What is the posterior pituitary gland made of?
neurons
What does the posterior pituitary secrete?
-oxytocin
promotes uterine contraction, milk excretion
-ADH
promotes water reabsorption in the kidneys
What is the difference in the onset of activity for a protein hormone and a steroid hormone?
peptide hormones: seconds to minutes
steroid hormones: mins to hours
What does the anterior pituitary secrete?
LH, FSH, TSH, ACTH, GH
Diagram of the anterior pituitary?
page 101
What are the characteristics of the thyroid gland?
- located in the lower neck region just below the larynx
- influences metabolic rate
Diagram of the thyroid gland?
page 103
What are the two thyroid hormones produced in the thyroid gland?
T3 and T4
both use the AA tyrosine as the basic building block to which iodide is added
-need iodide and thyroglobulin
-made in colloid, not the cell
Where does the iodide come from that is needed in T3 T4 production?
comes from the diet
attaches itself to large protein thyroglobulin
What are the 2 types of transports in the thyroid gland?
- active transport on the basolateral membrane
- facilitated diffusion on the apical membrane
diagram page 105
What is hyperthyroidism?
- Grave’s Disease: antibody to TSH receptor
- trophic hormone
- too much T3/T4
- elevated metabolic rate
- increased HR, sensitive to heat, weight loss, irritable
What is hypothyroidism?
- autoimmune destruction
- iodide deficiency
- atrophy
- not enough T3/T4
- lower metabolic rate
- decreased HR, sensitive to cold, weight gain, fatigue, depression
How does the negative feedback system work in the thyroid gland?
diagram page 107
What is the structure of the adrenal glands
- sit on top of kidneys
- 2 major regions: adrenal cortex and adrenal medulla
Diagram of the adrenal glands?
page 109
What does the zona glomerulosa make?(cortex)
aldosterone
What does the zona fasciculata make?(cortex)
cortisol
