Topic Five

• Permissveness

  one hormone only elicits its full effect in the presence of another hormone
• Example of permissivness

  • epinepherine and TH released together releases large amounts of fatty acids
• the same hormone can act on multiple receptors to elicit divergent effects
• Ghrelin

  1. orexigenic hormone
  2. peptide of the motilin family
• endocrine cells in the stomach line epithleium and secrete into the bloodstream of lining the stomach
• Metabolic actions of ghrelin

  1. increases lipogenesis
  2. increases gluconeogenesis
  3. increases angeogenesis
• enteroendocrine cells

  specialiized secretory cells in the small and large intestine
• ozempic

  modifications to GLP-1 peptide
• Modifications to GLP-1

  1. AA substitution at position 8 and 34
  2. spacer at position 26
  3. additional C-18 fatty diacid chain
• Leptin is a __________ hormone

  peptide
• Function of leptin

  • regulation of metabolism
• Leptin is an anorexogenic hormone
• ANP

  atrial natriuretic peptide
• BNP

  b-type natriuretic peptide
• What does ANP signal;

  1. reduce Na+ uptake in kindey
  2. reduce aldosterone release from adrenals
  3. reduce water uptake in kidney
• aldosterone

  1. steroid hormone produced in adrenal cortex
  2. increase Na+ absorption
  3. works with AVP to increase water uptkae in kidney
• Pineal gland

  • prodcues melatonin
  • pinealocytes cells (glial cells)
• melatonin levels peak at night
• MT1 is used for long term storage b/c it has direct genomic effects

  • uses cAMP and PKA
• MT2 is used for short term repsonse

  • uses DAG and PKC
• Half life of hormones; amount of time required for half the molecules to become inactivated or cleared from circulation
• exopeptidases act on carboxyl or amino ends of proteins
• endopeptidases act on specific sites within a protein