Use autocrine growth factors and has no down regulation
Difference b/w autocrine and juxtacrine Correct Answer same cell vs neighbouring cell
Both have 2 step process
Agonist vs antagonist examples Correct Answer Cortisol -> agonist effect on mineralocorticoid to maintain ion and water balance
Spironalactone -> Antagonist prevention of mineralocorticoid receptor binding and MRE element function
Ways to induce negative hormone feedback Correct Answer -restrict receptor expression
-restrict hormone level or availability
-phosphorylation to induce structural changes that degrade or inactivate ligand or receptors
Amount of hormone in interstitial space Correct Answer Amount of specific hormones can dictate response
Eg. The synergistic response from GH and TH together
Mammary Cells and Protein Synthesis Correct Answer -Prolactin and Insulin together drastically increase B-casien protein synthesis
-protein synthesis stays at one level with just prolactin
This experiment involved mammary cells incubated with prolactin alone or prolactin w/ insulin to see synergistic effect
Hormones that use blood binding proteins Correct Answer peptide hormones (IGF-1, GH)
IGF-1 Correct Answer -Has specific receptors in most cells except LIVER/ADIPOSE
-bioavailability determined by amount of BBP
-protein hormone (70aa)
IGF-1 pathway in growth Correct Answer 1. Hypothal releases GHRH
2. Ant Pit. Releases GH that attaches to GHBP
3. GHBP brings GH to JAKSTAT receptor
4. MAPK/STAT produces IGF-1
5. IGFBP brings it to IGF-1 receptor = Growth Endocrine disease Correct Answer -Hypo or Hyper
Hypo = chronic inflammation of pancreas leads to lack of insulin secretion
Hyper = muscle training causes hyperplasia from testosterone release
Insulin + Prolactin Correct Answer synergistically stimulate B-casein mrna translation by
cytoplasmic polyadenylation
Hormones effect on transcription Correct Answer hormones can activate or repress transcription
Eg. Tamoxifen stimulates EF sites to repress transcription (antagonist effect)
Protein Processing (Hepcidin example) Correct Answer 1. Preprohormone (85aa) signal
pep-hormone-cryptic tail
2. Pro hormone (60aa) hormone - cryptic peptide
3. Mature hepcidin (25aa) cryptic cleaved and post translation modifications added
Post-translational modifications Correct Answer -glycosylation
-phosphorylation
-acetylation
-methylation
-disulphide bridges
Coat Proteins Correct Answer COP 1 = retrograde (Golgi back to ER)
COP II = enterograde (ER to Golgi)
Clathrin = Golgi to plasma membrane
Mrna half life Correct Answer 5' cap and 3' poly A tail determines mrna half life
Hormone storage Correct Answer peptide hormones are released immediately (regulation area)
Neurotransmitters can be stored to be released at a time of fight or flight
Receptor Concentration Correct Answer Find [HR] to determine receptor concentration
Experiment = use antibodies on receptor and then measure [HR]
-faster you reach R0 the higher the affinity to that hormone
Scatchard Plot Correct Answer Wastes less hormones
The inverse of the slope = receptor affinity for the hormone
4 types of cell surface receptors Correct Answer 1. GCPR - adenyl cyclase or phospholipase C
2. GF receptors - tyrosine receptors
3. Cytokine receptors
4. Guanylyl Cyclase receptor