Intro to Hormones S2M1

  1. Paracrine messengers have what characteristics
    They are secreted locally and act on tissues in close proximity, but are too short lived to be carried far by the blood
  2. Prostaglandins are an example of what kind of messenger
    Paracrine messenger
  3. What are the characteristics of hormones
    Soluble substances that are carried by the blood stream to coordinate responses from multiple organs and tissues
  4. Insulin is an example of what kind of messenger
    Hormone
  5. Epinephrine is an example of what type of messenger
    Hormone
  6. Norepinephrine is a neurotransmitter of what type of neurons
    Post ganglionic, sympathetic, noradrenergic neurons
  7. Steroids are made primarily where
    In specialized endocrine glands
  8. Cholesterol, testosterone, and cortisol are examples of
    Steroid hormones
  9. All steroid hormones have the ability to have what effect
    Regulate transcription factors
  10. What are the only two thyroid hormones
    • Thyroxine (T4)
    • Triiodothyronine (T3)
  11. What elemental component of thyroid hormones makes them unique from almost all other substances in the body
    They have iodine in their structure
  12. What is the role of Thyroid hormones
    They increase the metabolic rate and have developmental effects (This is why they are crucial at birth)
  13. Thyroid hormones are made from
    Protein bound tyrosine
  14. Oxygenase
    Enzyme that uses molecular oxygen as one of the substrates
  15. Prostaglandins are made where
    In all tissues
  16. Cyclooxygenase is a key enzyme in the synthesis of what, and how does it work
    • Prostaglandins, Thromboxane, and Prostacyclin
    • It adds a carbon ring and oxygen
  17. Catecholamines function as both
    Hormones and neurotransmitters
  18. What are two primary Catecholeamines
    • Dopamine
    • Epinephrine
  19. Where is epinephrine a major hormone
    Adrenal medulla
  20. What breaks down the Catecholamines
    • MAO and COMT
    • MAO removes the nitrogen
    • COMT attaches a methyl group
  21. Most hormones found in the body are which type
    • Proteins or small peptides
    • Made by non-endocrine tissues
  22. Pituitary hormones belong to what category of hormones
    Protein/Small peptides hormones not synthesized by endocrine tissue
  23. What are some Hormone-like proteins
    Cytokines and Growth factors
  24. Growth Hormone and Prolactin fall under what family
    Protein Hormone family
  25. LH, FSH, and TSH fall under what hormone family
    Glycoproteins (Protein hormones)
  26. Adrenocorticotropic hormone (ACTH), Oxytocin, Vasopressin (ADH), and endorphins fall under what family
    Small peptide hormones
  27. What is the difference between Insulin, Proinsulin, and Preproinsulin
    • Preproinsulin is proinsulin before the signal peptide is removed (still in ribosome)
    • Proinsulin is insulin before the C-peptide is removed
    • Insulin lacks the C-peptide and Signal peptide
  28. What portion of preproinsulin is found in the ER
    Proinsulin
  29. Proinsulin is necessary for creating what in eventual insulin
    Disulfide bonds
  30. Where do the disulfide bonds found in insulin form
    In the ER
  31. What is used to cut out the C-peptide from the proinsulin
    Endopeptidase (prohormone convertase)
  32. What is the difference in concentration of C-peptide and insulin, and why is it important
    • They are exactly equal
    • It is used to test for the amount of insulin in the body
  33. Why is C-peptide a better marker then Insulin for blood insulin levels
    • It lasts longer in the blood
    • Can be used in patients that get insulin injections that don't contain the C-peptide (measuring endogenous secretion only)
  34. What is the path to make Angiotensin II in the blood stream
    • Kidney pressure is high
    • Renin is released
    • Renin breaks Angiotensinogen to Angiotensin I
    • Angiotensin Converting Enzyme (lungs and capillaries) converts Angiotensin I to Angiotensin II
  35. What is the effect of Angiotensin II in the blood stream
    • Increases blood pressure
    • Contracts smooth muscle on vessels directly
    • Causes the release of Aldosterone from the adrenal cortex causing retention of water by the kidneys
  36. Where and When is Renin secreted
    Juxtaglomerular cells when the intraglomerular pressure is too low
  37. ACE inhibitors do what
    • Inhibit Angiotensin Converting Enzyme and are therefore used for Hypertension
    • They also inhibit the break down of Bradykinin (vasodilator)
  38. What is the most common method for determining Hormone levels in the blood
    • Radioimmunoassay
    • - Utilizing radioactively labeled hormones and a specific antibody for the Hormone
  39. Arachidonic acid is a precursor for what Eicosanoids
    • Prostaglandins
    • Thromboxane
    • Prostacyclin
    • Leucotrienes
  40. Arachidonic acid (20 carbon amino acid) is made into Eicosanoids via what Enzymes
    • Cyclooxygenase
    • - Prostaglandins
    • - Thromboxane
    • - Prostacyclin
    • 5- lipoxygenase
    • - Leucotrienes
  41. Eicosapentaenoic acid is important why
    It is a precursor to Prostaglandins and is an Omega-3 fatty acid (Arachidonic acid - Omega-6)
  42. Phospholipase A2
    Breaks down membrane lipids to Arachidonic acid
  43. What is the first stable product of prostaglandin synthesis
    PGH2
  44. What does the subscript of PGE2 (Prostaglandin E) represent
    The number of double bonds outside the ring
  45. Prostaglandins have what types of actions
    • Platelet aggregation
    • Vasodilation
    • Uterine contraction
    • Inflammation
    • Fever
    • Reduced gastric acid secretion
  46. What are the roles of Thromboxane (TXA2) and Prostacyclin in platelet activation
    • Prostacyclin increases cAMP preventing platelet activation
    • Thromboxane decreases cAMP triggering platelet activation
    • They are working equally against each other when there is no damage in the tissues
  47. 5-lipoxygenase is important for
    Making biologically active products from polyunsaturated fatty acids (Arachidonic acid), most importantly Leucotrienes
  48. What are the systemic effects of Leucotrienes
    They participate in inflammation and allergy response (contract bronchial smooth muscles)
  49. Glucocorticoid drugs have what effect
    Anti-inflammatory steroids that inhibit phospholipase A2 preventing it from releasing Arachidonic acid from membranes, thus decreasing both Leucotrienes and Prostaglandins
  50. Non steroidal anti-inflammatory drugs (NSAIDs) have what affect
    • They inhibit Cyclooxygenase preventing the formation of Prostaglandins but not Leucotrienes
    • They reduce inflammation, pain, fever, and platelet aggregation
    • Can cause gastritis and peptic ulcers
    • Contraindicted with asthma
  51. What are the isoenzymes of cyclooxygenase and their locations in the body
    • COX-1 Most tissues
    • COX-2 WBC
    • COX-3 Brain (important for pain and fever)
  52. Aspirin is used for prevention of MI's because
    It inhibits COX-1 in platelets, it also inhibits COX-3, and even COX-2 at high doses
  53. What over the counter drug inhibits COX-3
    Acetominophen (important for pain and fever)
Author
lancesadams
ID
88709
Card Set
Intro to Hormones S2M1
Description
Biochem
Updated