How do hormones act? Which hormones do this?
All hormones act by binding to highly specific receptor proteins on membrane of target cell OR inside cell.
What are three adj to describe the endocrine system?
Slow, indirect, and long-lasting
What system does the endocrine system work with? How?
Nervous system - a lot of endocrine glands are stimulated by neurons to secrete their hormones.
What are the three basic chemistry types of hormones?
Peptides, steroids, and tyrosine derivatives
What is the path of the synthesis and distribution of peptide hormones? (4)
(11) Produced in Rough ER (like proteins) (2) Cleaved in the ER lumen (3) Golgi (4) secreted in vesicles via exocytosis
How do peptide hormones enter their target cells? Effects? (4)
Membrane-bound receptor & act via 2ndary messengers
Can act as ion channel (increasing membrane permeability), act/deact other ion channels, or activate secondary messengers.
What are the 11 peptide hormones that you need to know and where are they from?
(1) Anterior Pituitary hormones - FSH, LH, ACTH, hGH, TSH, Prolactin
- (2) Posterior pituitary: ADH, oxytocin
- (3) Parathyroid hormone
- (4) Insulin & Glucagon from Pancreas
Where are the only 3 places that steroid hormones come from?
Adrenal cortex (gluco/mineralcorticoids; cortisol & aldosterone)
Gonads/Placenta (Estrogen, progesterone, testosterone)
Where are steroid hormones produced? How do they enter cell? (3)
Finally, on what level do they act upon?
Steroid hormones are produced in the Smooth ER and Mitochondria
Nonpolar, so diffuse through plasma membrane and combines with cytosolic receptor --> nucleus --> steroids act at transcription level.
Can proteins diffuse through the plasma membrane?
How do tyrosine derivatives enter cells?*
Split: Thyroid hormones (T3 & T4) diffuse through nucleus. Catecholamines (NE & Epinephrine) act on membrane receptors.
If a hormone acts on a membrane receptor, what can you infer?
That the hormone might work as a secondary messenger activator
What are the 6 hormones in the anterior pituitary gland and what do each of them do?
- 1. hGH - growth of nearly all cells
- 2. ACTH (Adrenocorticotropic hormone) - stimulate sadrenal cortex to release glucocorticoids via 2nd messenger
- 3. TSH (Thyroid Stimulating) stimulates thyroid to release T3 and T4 & increases thyroid cell size/number
- 4. FSH - growth of follicles in female; sperm production in males
- 5. LH (Leutinizing) - causes ovulation; stimulates estrogen & testosterone secretion
- 6. Prolactin - promotes milk production.
What are the 2 posterior pituitary hormones and what do they do?
What type of chemical hormones?
Oxytocin - milk ejection & uterine contractions
ADH - water absorption by kidney & increase in blood pressure
What is needed for pituitary hormones to be secreted?
Signal from hypothalamus via nervous system