Hormones Flashcards
Glycoprotein hormones of αβ heterodimeric structure
- follicle-stimulating hormone (FSH)
- luteinizing hormone (LH)
- thyroid-stimulating hormone (TSH)
- chorionic gonadotropin (CG)
Chemical diversity of hormones.
(A) cholesterol derivatives;
(B) tyrosine derivatives;
(C) peptides of various sizes
(D) glycoproteins (TSH, FSH, and LH) with common α subunits and unique β subunits.
Required enzymes:
hydroxylases are essential and require molecular oxygen and NADPH,
- dehydrogenases,
- an isomerase,
- a lyase reaction are also necessary for certain steps.
Dopamine, norepinephrine (noradrenaline) and epinephrine (adrenaline) are:
synthesized from tyrosine in the chromaffin cells of the adrenal medulla.
norepinephrine is made in situ in organs innervated by
sympathetic nerves (about 80% of the total)
Which hormones are
made from larger peptide precursors
- Insulin
- PTH
- angiotensin II
- pro-opiomelanocortin (POMC) protein
PTH
- pre pro: 115 a.a. pre to pro
- pro: 90 a.a. pre to pth
- PTH:
Insulin
- what are the three target tissues ?
- what inhibits insulin ? what hormone is an antagonize insulin ?
- The release and synthesis of insulin is promoted by what molecules ?
- which tissue does insulin stimulate glucose and fatty acid uptake
- high insulin triggers synthesis or degradation of triglycerides ? pick one
- explain why the brain and red blood cells are NOT influenced by insulin metabolism ?
- liver, adipose tissues and skeletal muscle
- high concentrations of epinephrine
- glucose glucagon and fatty acids
- adipose tissue
- synthesis (anabolic)
- because the brain and red blood cells don’t have insulin receptors
Main regulatory molecules
- insulin
- glucagon
- catecholamines
- glucocorticoids (slower, stress-related changes)
- cytokines
A. The second messenger is cAMP
- α2 -Adrenergic catecholamines
- β-Adrenergic catecholamines
- Adrenocorticotropic hormone (ACTH)
- Antidiuretic hormone (ADH, vasopressin) in kidneys
- Calcitonin
- Chorionic gonadotropin, human (CG)
- Corticotropin-releasing hormone (CRH)
- Follicle-stimulating hormone (FSH)
- Glucagon Lipotropin (LPH)
- Luteinizing hormone (LH)
- Melanocyte-stimulating hormone (MSH)
- Parathyroid hormone (PTH)
- Somatostatin
- Thyroid-stimulating hormone (TSH)
Somatostatin
Function
- What hormones does somatostatin inhibit ?
- Somatostatin is a peptide hormone released by ?
- what does it do in the GI system ?
Effect of Somatostatin in the brain
- what hormones in regards to the brain does somatostatin inhibit ?
Function
- gastrin, secretin, histamine, insulin and glucagon
- delta cells (intestines) and hypothalamus
- decrease gastric emptying and pancreatic release of hormones
Effect of somatostatin in the brain
- Growth Hormone
- PRL
- TSH
Melanotropins
- what are melanotropins ?
- where are they released ?
- what MSH (melonocyte stimulating hormone) do ?
- effect of MSH on skin
- what does it help stimulate and release from the anterior pituitary gland ?
- peptide hormones of alpha beta and gamma by POMC
- secreted by the hypothalamus and the pituitary gland
- hunger suppressant and regulates libido
- protects skin from UV, stimulates melanocytes (melanogenesis)
- Prolactin
Growth Hormone
REGULATION
- what type of hormone is the Growth hormone ?
- where is the hormone secreted from
- how is the hormone regulated ?
- what is the two hormones in the hypothalamus that regulates GH ?
- what does GHIH do ?
- what does GHRH do ?
MECHANISM OF ACTION
- which type of receptor does the GH bind to ?
- when the hormone binds to the receptor what happens next ?what does the hormone activate ?
- name two types of signaling pathway?
FUNCTION
- What type of principle does the growth hormone imply ?
- what are some examples of tissues that the hormone stimulate proliferation ?
- how does the GH relate to the liver ? what is its role ?
- what is somatomedin C
- what does IGF-1 ( Somatomedin C) do ?
Favors Anabolic Reactions: give examples
REGULATION
- The growth hormone is a peptide hormone
- hypothalamus
- the hormone is regulated in the hypothalamus by two hormones
- GHRH and GHIH
- GHIH - inhibits growth
- GHRH - stimulates growth
MECHANISM OF ACTION
- binds to receptor of cell membranes
- the hormone-receptor complex activates a series of protein kinases
- the two types of signaling pathway is:
MAPK/ERK (Signaling- pathway)
JAK-STAT (signaling pathway)
FUNCTION
- The hormone is an ANABOLIC hormone (stimulates GROWTH)
- chondrocytes, cartilage, extension of bone, height
- stimulate the LIVER - to release Insulin-like GROWTH FACTOR) IGF -1
- Somatomedin C is IGF-1 released from the liver ( initiated by the stimulation of GH)
- helps other tissue grow
Favors Anabolic reactions
- protein synthesis
- Gluconeogenesis
- Lipolysis
- Calcium retention (mineralization of bones)
- increases in muscle mass
